ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles  (462)
  • Triticum aestivum  (266)
  • RFLP  (201)
  • Springer  (462)
  • Oxford University Press
  • 1990-1994  (462)
Collection
  • Articles  (462)
Keywords
Publisher
  • Springer  (462)
  • Oxford University Press
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 58 (1991), S. 69-74 
    ISSN: 1570-7458
    Keywords: Rhopalosiphum padi ; antixenosis ; plant resistance ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Die Antixenose gegenüberRhopalosiphum padi (L.) in den drei Weizensorten Timmo, Moghan 2 und Ommid, von denen die zwei letzteren Sorten aus dem Iran stammen, wurde unter Verwendung des systemischen Insektizids Pirimicarb gemessen. Jeweils zwei Pflanzen aus verschiedenen Sorten wurden als Paar verwendet (in allen Kombinationen der drei Sorten), pro Paar ein Topf mit Pirimicarb gegossen, und zwanzig Blattlaüse über Blattflächen von beiden Sorten gekäfigt. Ähnliche Versuche wurden auch ohne Insektizid ausgeführt. Beide Methoden zeigten deutliche Antixenose von Moghan 2 und Ommid in Vergleich mit Timmo. Die Insektizidmethode zeigte auch eine Bevorzugung von Moghan 2 gegenüber Ommid, ein Resultat, das mit der schon bekannten relativen Antibiose dieser zwei Sorten übereinstimmte, während sich ohne Insektizid kein solcher Unterschied erwies. Die statistische Analyse solcher Versuche mit einem Insektizid, die eine Modifikation der Berechnung des erwarteten Werts mit dem χ2 Test enthält, ist beschrieben.
    Notes: Abstract Antixenosis in three wheat varieties (Timmo, Moghan 2 and Ommid) toRhopalosiphum padi (L.) was measured by pairing plants of any two varieties with one plant of each pair treated with a soil drench of the systemic insecticide pirimicarb. Aphids were then allowed access to equivalent leaf areas from the two plants in a leaf cage. The results were compared with similar choice experiments without insecticide. By either technique, the two Iranian varieties (Moghan 2 and Ommid) showed antixenosis in comparison with Timmo. The statistical analysis of the data, using a heterogeneity χ2 test, is described.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1570-7458
    Keywords: LepidopteraEphestia kuehniella ; α-amylase ; Triticum aestivum ; endosperm ; α-amylase inhibitors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Crude α-amylase preparations from seven Lepidoptera pests were susceptible to inhibition by salt-soluble proteins of bread wheat (Triticum aestivum L.) endosperm. Protein fractions that corresponded to tetrameric, dimeric, and monomeric wheat α-amylase inhibitors, were decreasingly effective against the insect α-amylase activity. To further confirm these results, purified inhibitors were tested against an α-amylase preparation fromEphestia kuehniella (Zeller). This preparation showed decreased activity when increasing amounts of an heterotetrameric inhibitor (reconstituted from its isolated subunits WTAI-CM2, -CM3 and -CM16) were assayed. Activity was only partially inhibited by homodimeric (WDAI-1, synonym 0.53; WDAI-2, synonym 0.19) and monomeric (WMAI-1, synonym 0.28) inhibitors.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 59 (1991), S. 79-85 
    ISSN: 1570-7458
    Keywords: Wheat ; Triticum aestivum ; cereals ; Rhopalosiphum padi ; Aphididae ; barley yellow dwarf virus ; hydroxamic acids ; DIMBOA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 2,4-Dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), a hydroxamic acid (Hx) occurring in wheat, was shown to deter feeding by the aphid Rhopalosiphum padi (L.), and to reduce BYDV transmission to the plant. Dual choice tests with wheat leaves showed the preferential settlement of aphids on leaves with lower levels of DIMBOA. Electric monitoring of aphid feeding behaviour showed that in seedlings with higher DIMBOA levels fewer aphids reached the phloem and they needed longer times to contact a phloem vessel than in those with lower levels. When aphids carrying BYDV were allowed to feed on wheat cultivars with different DIMBOA levels, fewer plants were infected with BYDV in the higher DIMBOA cultivars than in the lower ones. Preliminary field experiments showed a tendency for wheat cultivars with higher Hx levels to be more tolerant to infection by BYDV than lower Hx level ones.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1420-9071
    Keywords: Mitochondrial DNA ; RFLP ; Leptinotarsa decemlineata ; Colorado potato beetle ; population genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary This study demonstrates variability in restriction enzyme cleavage sites of mitochondrial DNA (mtDNA) among four popalations of Colorado potato beetle (CPB). A suite of three enzymes (EcoRI,HpaI,PstI) was sufficient to discriminate among the populations tested. Individuals heteroplasmic for restriction enzyme patterns were found in some populations. Variability in CPB mtDNA should prove useful in efforts to trace the origin and dispersal of the species in North America.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Biology and fertility of soils 9 (1990), S. 281-282 
    ISSN: 1432-0789
    Keywords: Surface sterilization ; Contaminants ; Sterile plant selection ; Axenic seedlings ; Triticum aestivum ; Trifolium pratense ; Trifolium repens
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Sterile seedlings are required for the investigation of interactions between microorganisms and plants. The present study was designed to develop a simple and reliable method for the selection of sterile seedlings by the use of liquid nutrient media, avoiding some of the disadvantages of solid media. The method of germinating surface-sterilized seedlings on solid water agar or nutrient media was compared with our method for sterility control in nutrient broth. Sterile plant selection in liquid media was the most sensitive method for detecting bacterial and fungal contaminants. Sterile plants grow with the same vigour as unsterilized plants and can be used for sterile plant experiments.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1432-0983
    Keywords: Secale cereale ; Triticum aestivum ; Ribosomal RNA genes ; Mitochondrial DNA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The mitochondrial 18S and 5S ribosomal RNA (rRNA) genes of rye, plus a total of about 90 kilobase pairs of flanking DNA, have been cloned and maps of restriction enzyme cleavage sites have been constructed. Like their homologs from hexaploid wheat, the rye genes are closely linked and are part of a three-copy family of recombining repeats (the “18S/5S repeat”). The rye repeat probably also contains a mitochondrial tRNAfMet gene, which the wheat repeat is known to carry. However, despite the overall organizational similarity between the wheat and rye 18S/5S repeats in the immediate vicinity of their coding regions, extensive rearrangement of flanking sequences has taken place during evolutionary divergence of the two species. Our data provide additional support for an emerging picture of plant mitochondrial genomes as evolving much more rapidly in structure than in sequence.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1432-0983
    Keywords: Light regulation ; psbN ; Triticum aestivum ; Etioplast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The nucleotide sequence of a region of wheat chloroplast DNA containing the psbB gene for the 47 kDa chlorophyll a-binding protein of photosystem II has been determined. The gene encodes a polypeptide of 508 amino acid residues which is predicted to contain six hydrophobic membrane-spanning regions. The psbB gene is located 562 bp upstream of the psbH gene for the 10 kDa phosphoprotein of photosystem II. A small open reading frame of 38 codons is located between psbB and psbH, and on the opposite strand the psbN gene, encoding a photosystem II polypeptide of 43 amino acid residues, is located between orf38 and psbH. S1 nuclease mapping indicated that the 5′ ends of transcripts were located 371 and 183 bp upstream of the psbB translation initiation codon. Predominant transcripts of 2.1 kb and 1.8 kb for psbB and 0.4 kb for psbH were present in RNA isolated from etiolated and greening wheat seedlings. Immunodecoration of Western blots indicated that the 47 kDa polypeptide was absent, or present in very low amounts, in dark-grown tissue and accumulated on greening, whereas the 10 kDa polypeptide was present in similar amounts in both dark-grown and greening seedlings. The 10 kDa polypeptide was phosphorylated in vitro by incubating wheat etioplast membranes with [γ3 2P] ATP.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1432-0983
    Keywords: Triticum aestivum ; Mitochondrial DNA ; Chloroplast DNA ; ATPase alpha subunit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary An internal part of the chloroplast atpA gene has been identified in the mitochondrial DNA of Triticum aestivum. It is located near the 18S-5S ribosomal genes and partially contained within a repeated sequence. Comparison of the transferred sequence with the original ct sequence reveals several nucleotide changes and shows that neither 5′ nor 3′ ends are present in the mt genome. No transcript of this region could be detected by Northern analysis. This sequence is present in mitochondrial genomes of other tetraploid and diploid species of Triticum, also in the vicinity of the 18S-5S ribosomal genes, suggesting a unique transfer event. The date of this event is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 40 (1994), S. 207-214 
    ISSN: 1573-0867
    Keywords: available P ; citrate insoluble P ; phosphorus sources ; triple superphosphate ; Triticum aestivum ; water soluble P ; wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract A greenhouse study was conducted to determine if soil pH affects the requirement for water-soluble P and the tolerance of water-insoluble impurities in TSP fertilizers. Two commercial TSP fertilizers were selected to represent a range in phosphate rock sources and impurities. Phosphate fertilizer impurities were isolated as the water-washed fraction by washing whole fertilizers with deionized water. TSP fertilizers with various quantities of water-soluble P (1.2 to 99% water-soluble P) were simulated by mixing the water-washed fertilizer fractions or dicalcium phosphate (DCP) with reagent-grade monocalcium phosphate (MCP). The fertilizers were applied to supply 40 mg AOAC available P kg−1 to a Mountview silt loam (fine-silty, siliceous, thermic Typic Paleudults). Wheat (Triticum aestivum (L.)) was harvested at 49 and 84 days after planting. Soil pH values at the final forage harvest were 5.4±0.16 and 6.4±0.15. At a soil pH of 5.4, the TSP fertilizers required only 37% water-soluble P to reach maximum yields while at pH 6.4 the fertilizers required 63% water-soluble P. Results of this study show that higher levels of water -insoluble P can be tolerated in TSP fertilizers when applied to acid soils. Phosphorus uptake was not affected by soil pH, but for the mixtures containing the fertilizer residues the source having the lowest level of Fe and Al had a higher relative agronomic effectiveness.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 39 (1994), S. 43-57 
    ISSN: 1573-0867
    Keywords: Bicarbonate soil test phosphorus ; relative effectiveness ; rock phosphate ; superphosphate ; Triticum aestivum ; ×Triticosecale
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The effect of water supply on the response of wheat (Triticum aestivum) and triticale (×Triticosecale) to levels of freshly-applied rock phosphate and superphosphate, and the residues of these fertilizers applied 9 years previously in the field, was studied in three glasshouse experiments. The 〈 2 mm fraction of the top 10 cm of soil was used (1.8 kg soil per pot), and in one experiment, freshly-applied fertilizer was also added to the more acidic subsoil (10 to 20 cm). There were two water treatments: the soil was returned to field capacity by watering to weight, either daily (W1, adequate water) or weekly (W2, water stress). Yield of dried tops was used to calculate fertilizer effectiveness. The phosphorus (P) concentration in dried tops was used to determine critical P, which is the P concentration related to 90% of the maximum yield. Just before sowing, soil samples were collected to measure bicarbonate-extractable (soil test) P which was related to plant yield. Water stress reduced yields and maximum yield plateaus by 20 to 40%. Water stress reduced the effectiveness of all P fertilizers by between 20 to 60%, largely because of a reduction in the maximum yield potentials. In the field, water supply is seasonally dependent and it can affect the yield response of plants to freshly-applied rock phosphate and superphosphate and the residues of these fertilizers applied to the field in previous years. Relative to placing fertilizer in the topsoil, placing fertilizer in the subsoil improved effectiveness by about 26% for rock phosphate and 12% for superphosphate. The relationship between yield and P concentration in dried tops, and critical P, differed for W1 and W2. The soil test P calibration, which relates yield to soil test P, and the soil test P required to produce the same yield also differed for W1 and W2. Consequently critical P and soil test P calibrations depend on water supply, which in the field varies within and between growing seasons. This is so for freshly- and previously-applied rock phosphate and superphosphate.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Agroforestry systems 20 (1992), S. 253-266 
    ISSN: 1572-9680
    Keywords: allelopathy ; shelterbelt ; soil phytotoxins ; Cicer arietinum ; Lens esculentum ; Triticum aestivum ; Brassica oleracea ; Trifolium alexandrinum ; Eucalyptus tereticornis ; Brassica campestris cv toria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The economic yield of chickpea, lentil, wheat, cauliflower, barseem, and toria in a 12-m-wide strip to the south of 8 ± 1-year-old Eucalyptus tereticornis shelterbelts (three different locations) was reduced by more than half. Among all the crops under study, the yield of chickpea was reduced by the maximum extent. The content of soil phytotoxins was maximum in the litter-free top soil surface, compared to that at 30 or 60 cm depths, at all distances from the Eucalyptus. Maximum content of phytotoxins was found at 1 m from the tree line for all depths. These soil phytotoxins impaired the germination of Lens esculentum, thus indicating an allelopathic effect. It is included that the poor perfornce of crops in the sheltered area is related to an allelopathic effect of the Eucalyptus.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    ISSN: 1420-9098
    Keywords: Leptothorax acervorum ; mtDNA ; RFLP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary 27 nests ofLeptothorax acervorum were analysed for restriction fragment-length polymorphism (RFLP) in mitochondrial DNA (mtDNA), using four endonucleases. A substantial degree of variation was found between nests in the population (13 composite haplotypes). Intra-nest variation was detected in 15 % of the nests. The presence of occasional alien inseminated females indicates that polygyny in this species is caused by adoption of mated females. The occasional acceptance of alien females is difficult to explain, but interesting, since this behaviour could have given rise to inquilinism. Our results suggest that analysis of mtDNA RFLP is a method well suited for investigations of the population structure of ants.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Oecologia 100 (1994), S. 221-228 
    ISSN: 1432-1939
    Keywords: Triticum aestivum ; Competition ; Abiotic stress ; Multiplicative interactions ; Nickel toxicity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Using recently developed solution culture techniques, the effect of a non-resource abiotic stress, nickel toxicity, was tested on intraspecific nutrient competition among wheat. The choice of an appropriate statistical model was of paramount importance in interpreting these effects. We argue that a multiplicative model is more appropriate for experiments on interactions of competition and abiotic stress. By such an analysis, nickel had no relative effect on the ability of competition to reduce plant size in two experiments, and caused a small reduction in competition in another. These results are contrary to other reports of the effect of a non-resource abiotic stress on competition and appear to be due to an increased demand for nutrients in the presence of toxic levels of nickel. The effects of an abiotic stress on competition may thus be specitic to the stress and not generalized across all abiotic stresses.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Electronic Resource
    Electronic Resource
    Springer
    Plant cell reports 12 (1993), S. 293-297 
    ISSN: 1432-203X
    Keywords: Lycopersicon esculentum ; Genetic marker ; Intraspecific genetic map ; DNA polymorphism ; Isozyme ; RFLP ; RAPD
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The existing molecular genetic maps of the tomato, Lycopersicon spp, are constructed based on isozyme and RFLP polymorphisms between tomato species. These maps are useful for certain applications but have few markers that exhibit sufficient polymorphisms for intraspecific analysis and manipulations within the cultivated tomato. The purpose of this study was to investigate the relative potential of RAPD technology, as compared to isozymes and RFLPs, to generate polymorphic DNA markers within cultivated tomatoes. Sixteen isozymes and 25 RFLP clones that were known to detect polymorphism between L. esculentum and L. pennellii, and 313 random oligonucleotide primers were examined. None of the isozymes and only four of the RFLP clones (i.e., 16%) revealed polymorphism between the cultivated varieties whereas up to 63% of the RAPD primers detected one or more polymorphic DNA fragments between these varieties. All RAPD primers detected polymorphism between L. esculentum and L. pennellii genotypes. These results clearly indicate that RAPD technology can generate sufficient genetic markers exploiting sequence differences within cultivated tomatoes to facilitate construction of intraspecific genetic maps.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    ISSN: 1432-203X
    Keywords: Protoplast fusion ; RFLP ; Mitochondrial DNA ; Chloroplast DNA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Somatic hybrid plants were recovered following fusion of leaf mesophyll protoplasts isolated from tomato (Lycopersicon esculentum) cultivar UC82 with protoplasts isolated from suspension cultured cells of L. chilense, LA 1959. Iodoacetate was used to select against the growth of unfused tomato protoplasts. Two somatic hybrids were recovered in a population of 16 regenerants. No tomato regenerants were recovered; all of the non-hybrid regenerants were L. chilense. The L. chilense protoplast regenerants were tetraploid. The hybrid nature of the plants was verified using species-specific restriction fragment length polymorphisms for the nuclear, chloroplast and mitochondrial genomes. The somatic hybrids had inherited the chloroplast DNA of the tomato parent, and portions of the mitochondrial DNA of the L. chilense parent. The somatic hybrids formed flowers and developed seedless fruit.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Electronic Resource
    Electronic Resource
    Springer
    Oecologia 91 (1992), S. 82-92 
    ISSN: 1432-1939
    Keywords: Plant disease ; Genetic diversity ; Frequency-dependence ; Triticum aestivum ; Puccinia striiformis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The direct and indirect effects of plant genetic diversity on epidemics and the influence of disease on plant competition were investigated using the wheat (Triticum aestivum)/stripe rust (Puccinia striiformis) system. Replacement series consisting of a susceptible and a resistant wheat genotype or two wheat genotypes susceptible to different races of stripe rust were grown in the presence and absence of the pathogen. Stripe rust severity, number of seed heads, seed yield, and seed weight were determined separately for each wheat genotype in the mixtures and the pure stands. The frequency of susceptible genotypes in a mixture explained up to 67% of the variation in disease severity. However, competitive interactions among plant genotypes sometimes appeared to alter susceptibility and obscured the relationship. In pure stands of single genotypes, disease severity explained between 52 and 58% of the variation in seed yield. In mixtures, coefficients of determination were only 10 and 31%, suggesting a strong influence of plant-plant interactions on seed yield. These results suggest that host-parasite coevolutionary models need to account for the strong effect that specific plant genotype combinations may have on disease severity and plant reproduction.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    ISSN: 1432-1939
    Keywords: Multispecies canopy model ; Canopy photosynthesis model ; Triticum aestivum ; Avena fatua ; Ultraviolet-B radiation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Competition for light among species in a mixed canopy can be assessed quantitatively by a simulation model which evaluates the importance of different morphological and photosynthetic characteristics of each species. A model was developed that simulates how the foliage of all species attenuate radiation in the canopy and how much radiation is received by foliage of each species. The model can account for different kinds of foliage (leaf blades, stems, etc.) for each species. The photosynthesis and transpiration for sunlit and shaded foliage of each species is also computed for different layers in the canopy. The model is an extension of previously described single-species canopy photosynthesis simulation models. Model predictions of the fraction of foliage sunlit and interception of light by sunlit and shaded foliage for monoculture and mixed canopies of wheat (Triticum aestivum) and wild oat (Avena fatua) in the field compared very well with measured values. The model was used to calculate light interception and canopy photosynthesis for both species of wheat/wild oat mixtures grown under normal solar and enhanced ultraviolet-B (290–320 nm) radiation (UV-B) in a glasshouse experiment with no root competition. In these experiments, measurements showed that the mixtures receiving enhanced UV-B radiation had a greater proportion of the total foliage area composed of wheat compared to mixtures in the control treatments. The difference in species foliage area and its position in the canopy resulted in a calculated increase in the portion of total canopy radiation interception and photosynthesis by wheat. This, in turn, is consistent with greater canopy biomass of wheat reported in canopies irradiated with supplemental UV-B.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Electronic Resource
    Electronic Resource
    Springer
    Sexual plant reproduction 5 (1992), S. 286-291 
    ISSN: 1432-2145
    Keywords: Triticum aestivum ; Spikelet culture ; In vitro pollen maturation ; Gametophytic selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Two spring wheat genotypes (cv Orofen and Chinese Spring) were compared for their in vitro pollen maturation capacity in detached spikelet cultures in a defined solid medium. Under these in vitro conditions Chinese Spring produced normal trinucleate pollen in 66.8% and Orofen in only 37.5%. In both cultivars the pollen maturation process from the middle uninucleate stage took approximately 3 days longer in vitro than in vivo. The pollen maturation time depended on the microspore developmental stage at the time that the culturing started. The viability, germination capacity, and fertilizing ability of the in vitro matured pollen also differed between the two genotypes. The seed set achieved in vitro (averagely 12.8%) offers promise for the practical application of this method for producing controlled or selected offspring.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    ISSN: 1432-2145
    Keywords: Flower ; Meristem ; Gene transfer Particle bombardment ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Direct gene transfer to floral meristems could contribute to cell-fate mapping, to the study of flower-specific genes and promoters, and to the production of transgenic gametes via the transformation of sporogenic tissues. Despite the wide potential of its applications, direct gene transfer to floral meristems has not been achieved so far because of the lack of suitable technology. We show in this paper that ballistic micro-targeting is the technique of choice for this purpose, and in this way, we were able to transfer genes efficiently into excised wheat immature spikes. Particle size was adjusted for optimal penetration into the L1 and L2 cell layers of the spikes with limited cell damage. Spikes at different developmental stages were shot either with a plasmid containing two genes involved in anthocyanin biosynthesis or with a plasmid bearing the uidA (β-glucuronidase) gene. The transient expression of these marker genes was observed in the different developmental stages tested and in cells of both the L1 and the L2 layers. The transient expression of the uidA gene was significantly increased when the sucrose concentration in the culture medium was increased from 0.06 to 0.52 M. At the highest concentration, 100% of the targeted spikes expressed the uidA gene, with an average of 69 blue cells per spike. Twelve days after microtargeting, multicellular sectors showing transgene expression and containing up to 17 cells were found in 85% of the shot immature inflorescences. This indicated that targeted cells survived particle bombardment. Sectors were found in primordia of both vegetative and reproductive organs.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    ISSN: 1432-2145
    Keywords: Gametophytic self incompatibilityself-compatibility ; Lycopersicon peruvianum Lycopersicon hirsutum ; S-associated proteins ; RFLP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Self-compatibility was investigated separately in two species of tomato, Lycopersicon peruvianum and L. hirsutum. The codominant expression of self-compatibility (SC)/self incompatibility (SI) was established using intraspecific hybrids of SC and SI hybrids. In SC L. peruvianum, a major stylar protein of approximately 29 kDa cosegregates with self-compatibility in the progeny of SC/SI hybrids. The SC/SI hybrids are self-fertile, but only partially so, since the SI allele present in the hybrids is capable of eliminating certain genotypes in the resultant progeny. In L. hirsutum, the majority of hybrids between one accession of SI L. hirsutum f. hirsutum and one of SC L. hirsutum f. glabratum are self-fertile. Analysis of the progeny revealed that the SC and SI alleles are codominant in this species as well. A protein product for the SC allele is not obvious in style extracts of L. hirsutum f. glabratum. Segregating progeny from SC/SI hybrids of L. hirsutum were used to map the S locus against five RFLP markers on chromosome 1, and estimated map distances are given. In addition, evidence is presented that indicates that one of the DNA markers, CD15, is duplicated in L. hirsutum f. glabratum, and the duplication is not linked to the S locus.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Electronic Resource
    Electronic Resource
    Springer
    Sexual plant reproduction 5 (1992), S. 247-255 
    ISSN: 1432-2145
    Keywords: Wheat ; Triticum aestivum ; Pollen germinability ; Intracellular movement ; Actin cytoskeleton ; Effects of dehydration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The tricellular pollen of wheat germinates rapidly on a receptive stigma without the often protracted activation period characteristic of bicellular pollens. This is associated with a high level of hydration in the mature pollen and the absence of a dormancy period. Intracellular movement of organelles continues throughout development; in the mature pollen along pathways related both to the aperture site and the distribution of the amyloplasts in the vegetative cell. The movement pathways reflect the organisation of the actin cytoskeleton, elements of which are already focused upon the germination site at the time of dispersal, a disposition only achieved during rehydration and activation in bicellular pollens. Dehydration after dispersal rapidly arrests movement, disrupts the actin cytoskeleton and leads to loss of germinability. These effects are irreversible, again in contrast to the situation found in bicellular pollens such as those of the Liliaceae, species of which have been shown to be capable of withstanding several cycles of hydration and dehydration while still retaining some capacity for germination.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    ISSN: 1432-203X
    Keywords: Rice (Oryza sativa) ; Genetic Marker ; Genetic Map ; Integrated Linkage Map ; RFLP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Application of genetic linkage maps in plant genetics and breeding can be greatly facilitated by integrating the available classical and molecular genetic linkage maps. In rice, Oryza sativa L., the classical linkage map includes about 300 genes which correspond to various important morphological, physiological, biochemical and agronomic characteristics. The molecular maps consist of more than 500 DNA markers which cover most of the genome within relatively short intervals. Little effort has been made to integrate these two genetic maps. In this paper we report preliminary results of an ongoing research project aimed at the complete integration and alignment of the two linkage maps of rice. Six different F2 populations segregating for various phenotypic and RFLP markers were used and a total of 12 morphological and physiological markers (Table 1) were mapped onto our recently constructed molecular map. Six linkage groups (i.e., chr. 1, 3, 7, 9, 11 and 12) on our RFLP map were aligned with the corresponding linkage groups on the classical map, and the previous alignment for chromosome 6 was further confirmed by RFLP mapping of an additional physiological marker on this chromosome. Results from this study, combined with our previous results, indicate that, for most chromosomes in rice, the RFLP map encompasses the classical map. The usefulness of an integrated genetic linkage map for rice genetics and breeding is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    ISSN: 1432-203X
    Keywords: Cell suspension ; Somatic embryogenesis ; Triticum aestivum ; Leymus angustus ; Plant regeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Embryogenic cell suspension cultures were established from Triticum aestivum X Leymus angustus F1 hybrids, using compact nodular calli derived from inflorescence segments. Calli originating from leaf segments did not give rise to stable cell suspensions. Growth measurements of the cell suspensions revealed that they continued rapid growth up to 10 days after subculturing. Flow cytometric studies of the cell cycle over a 7 day culture period showed that the majority of cells were in G1 phase while the rest were either in S or G2. During the 7 days of culture, no significant differences in DNA distribution patterns were observed. The cells from suspension cultures produced somatic embryos when they were transferred to different solid media. The embryos germinated and gave rise to plantlets which were successfully rooted and transferred to soil.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    ISSN: 1432-203X
    Keywords: Triticum aestivum ; embryogenic suspension cultures ; protoplasts ; regeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Highly regenerable callus cultures have been obtained from immature embryos of hexaploid wheat cv. Oderzo. Friable fast growing calli were induced at high frequency. Suspensions were initiated from the most friable callus lines: they became established in about two months. Suspensions consisted of cell aggregates of 30 to 1000 um in diameter. Upon plating on MS hormone-free medium, suspensions regenerated green plantlets, and their regenerative capability was maintained for at least 10 months. Protoplasts were isolated from 7–8 day old suspension cultures with a yield of 4–6×106 protoplasts/g fresh weight cells. Protoplast culture was either in liquid medium or in a bead-type system with agarose beads. First divisions were detected at day 5. At day 14 visible colonies were detected and the plating efficiency was evaluated between 2 and 8% over the initial number of protoplasts plated. Protoplast-derived calli were cultured in the presence of 1 mg/l IAA and 0.5 mg/l zeatin and were used for reinitiating new suspension cultures. Upon plating onto MS hormone-free medium, with or without the addition of 0.1 mg/l GA3, calliclones were induced to differentiate. Regeneration of complete plantlets, with shoot and roots took about two months. Plantlets were grown in sterile conditions until 12–15 cm height, and were subsequently transplanted in soil.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    ISSN: 1432-203X
    Keywords: cryopreservation ; Triticum aestivum ; abscisic acid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Spring wheat (Triticum aestivum L.) zygotic embryos were successfully cryopreserved, without the addition of exogenous cryoprotectants, using only an abscisic acid (ABA) pretreatment. Optimum survival was obtained when embryos were cultured in vitro for 10 days on semisolid Murashige and Skoog (MS) nutrient medium supplemented with 0.5 mg/L (±) ABA prior to cryopreservation. The embryos resumed growth within three days when returned to MS medium devoid of ABA but containing 2mg/L 2,4-dichlorophenoxyacetic acid. The embryogenic calli produced from these embryos exhibited normal plant regeneration on auxin-free media. Changes in dw/fw ratio, as well as the esterified fatty acid and sucrose concentrations correlated positively with the development of tolerance to cryopreservation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    Electronic Resource
    Electronic Resource
    Springer
    Plant cell reports 12 (1993), S. 149-153 
    ISSN: 1432-203X
    Keywords: Triticum aestivum ; microspore culture ; ovary co-culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Wheat microspores were isolated, without prior anther culture, from a range of genotypes and cultured to regenerate self-fertile plants. Microspores were isolated using a microblender and competent microspores were enriched by gradient centrifugation. The use of maltose as the sole carbohydrate in the culture medium and co-culture of microspores with wheat or barley ovaries were critical for development of microspore-derived embryos. Results were also improved when spikes were pretreated by emersion of the basal ends of detached heads in water at 25°C for 2d. This procedure leads to highly reproducible production of plants.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Electronic Resource
    Electronic Resource
    Springer
    Current genetics 26 (1994), S. 456-460 
    ISSN: 1432-0983
    Keywords: Parasitella parasitica ; Zygomycetes ; RAPD ; PCR ; RFLP ; Electrophoretic karyotype ; Molecular taxonomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In addition to conventional methods for the identification of fungi, molecular techniques at the DNA level are increasingly being employed. In order to check the validity of such experimental approaches, we have analyzed the well-defined species Parasitella parasitica, which belongs to the family Mucoraceae (Mucorales, Zygometes). The seven strains of this species, which are available from international strain collections, were analyzed by several molecular methods: restriction fragment length polymorphism analysis (RFLP), the random primer-dependent polymerase chain reaction (RAPD-PCR), and electrophoretic karyotyping. Unexpectedly, these strains are highly diverse at the molecular level. By these techniques they can be divided consistently into two different groups. Nevertheless, all seven strains belong to a single species. They show no morphological differences and sexual spores (zygospores) were found in all possible combinations either within or between the two groups. Southern-blot analysis of genomic DNA of all P. parasitica strains with RAPD-PCR-derived labelled probes shows the existence of repetitive elements characteristic for only one group of P. parasitica. In addition, chromosome sizes, which were separated by rotating-field electrophoresis, were highly divergent, and ranged from 3 to 6.5 Mb in one group and between 2 and 4.5 Mb in the other. The RAPD-PCR patterns also discriminate both groups of P. parasitica. However, they are very similar if strains of a single group are compared. Therefore, we propose that the determination of fungal species by molecular techniques should be vetted at least by morphological and physiological parameters and, whenever possible, by mating experiments.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    ISSN: 1432-0983
    Keywords: Mitochondrion ; Transcription ; Guanylyltransferase ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary To identify transcription initiation sites in wheat mitochondria, the nascent 5′-ends of transcripts were specifically labeled by incubation of wheat mitochondrial RNA with [α-32P]GTP in the presence of the enzyme guanylyltransferase. After separation of the resulting capped transcripts by electrophoresis in polyacrylamide gels, individual RNAs were recovered and directly sequenced. Four RNA sequences obtained in this way were localized upstream of the protein-coding genes atpA, coxII, coxIII and orf25. Comparison of mRNA and gene sequences allowed precise positioning of transcription initiation sites for these four genes. Sequence similarities immediately upstream of these sites define a conserved motif that we suggest as a candidate regulatory element in wheat mtDNA. The relationship between this motif and putative mitochondrial promoters in other plant species is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    ISSN: 1432-0983
    Keywords: Reciprocal recombination ; Mitochondrial genome ; Chondriome variability ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The mitochondrial genome of the selfed progeny of a plant regenerated from long-term somatic tissue culture displays specific structural rearrangements characterized by the appearance of novel restriction fragments. A mitochondrial DNA library was constructed from this selfed progeny in the SalI site of cosmid pHC79 and the novel fragments were subsequently studied. They were shown to arise from reciprocal recombination events involving DNA sequences present in the parental plant. The regions of recombination were sequenced and the nucleotide sequences were aligned with those of the presumptive parental fragments. We characterized an imperfect short repeated DNA sequence, 242 bp long, within which a 7-bb DNA repeat could act as a region of recombination. The use of PCR technology allowed us to show that these fragments were present in both parental plants and tissue cultures as low-abundance sequence arrangements.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Electronic Resource
    Electronic Resource
    Springer
    Biology and fertility of soils 17 (1994), S. 232-236 
    ISSN: 1432-0789
    Keywords: 15N-labelled fertilizer ; Added N interaction ; Fertilizer N uptake ; Soil N uptake ; Wheat ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract We studied the effects of 15N-labelled ammonium nitrate and urea on the yield and uptake of labelled and unlabelled N by wheat (Triticum aestivum L., cv. Mexi-Pak-65) in a field experiment. The dry matter and N yields were significantly increased with fertilizer N application compared to those from unfertilized soil. The wheat crop used 33.6–51.5 and 30.5–40.9% of the N from ammonium nitrate and urea, respectively. Splitting the fertilizer N application had a significant effect on the uptake of fertilizer N by the wheat. The fertilizer N uptake showed that ammonium nitrate was a more available source of N for wheat than urea. The effective use of fertilizer N (ratio of fertilizer N in grain to fertilizer N in whole plant) was statistically similar for the two N fertilizers. The application of fertilizer N increased the uptake of unlabelled soil N by wheat, a result attributed to a positive added N interaction, which varied according to the fertilizer N split; six split applications gave the highest added N interaction compared to a single application or two split applications for both fertilizers. Ammonium nitrate gave 90.5, 33.5, and 48.5% more added N interaction than urea with one, two, and six split N applications. A values were not significantly correlated with the added N interaction (r=0.557). The observed added N interaction may have been the result of pool substitution, whereby added labelled fertilizer N replaced unlabelled soil N.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    ISSN: 1432-0983
    Keywords: Triticum aestivum ; Secale cerele ; Ribosomal RNA genes ; Mitochondrial DNA ; Recombining-repeats ; Evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The mitochondrial genomes of wheat and rye each contain a three-member family of recombining repeat peat sequences (the “18S/5S repeat”) that encode genes for 18S and 5S rRNAs (rrn18 and rrn5) and tRNAfMet (trnfM). Here we present, for wheat and rye, the sequence and boundaries of the “common sequence unit” (CSU) that is shared between all three repeat copies in each species. The wheat CSU is 4,429 base-pairs long and contains (in addition to trnfM, rrn18 and rrn5) a putative promoter, three tRNA-like elements (“t-elements”), and part of a pseudogene (“ψatpA c”) that is homologous to chloroplast atpA, which encodes the α subunit of chloroplast F1 ATPase. The rye CSU is somewhat smaller (2,855 base pairs) but contains much the same genic and other sequence elements as its wheat counterpart, except that two of the three t-elements as well as ψatpA c are found in only one of the three downstream flanks of the 18S/5S repeat, outside the CSU boundaries. In interpreting the seuuence data in terms of the evolutionary history of the 18S/5S-repeat family of wheat and rye, we conclude that (1) the wheat-rye form of the 18S/5S repeat most likely originated between 3 and 14 million years ago, in a lineage that gave rise to wheat and rye but not to barley, oasts, rice or maize; (2) the close linkage (1-bp apart) between trnfM and rrn18 is similarly limited in its taxonomic distribution to the wheat/rye lineage; (3) the trnfM-rrn18 pair arose via a single mutation that inserted a sequence block containing trnfM immediately upstream of rrn18; and (4) the presence of a putative promoter upstream of rrn18 in all wheat and rye repeats is consistent with all three repeat copies being transcriptionally active. We discuss these conclusions in the light of the possible functional significance of recombining-repeats in plant mitochondrial genomes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    ISSN: 1432-0983
    Keywords: Cytoplasmic male sterility ; Antisense RNA ; RFLP ; Cybrids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Asymmetric cell-fusion of the japonica cultivar ofOryza sativa (rice) with cytoplasmic-male-sterile (CMS) plants bearing cytoplasm derived from Chinsurah Boro II, resulted in two classes of cytoplasmic hybrids (cybrids), fertile and CMS. Southern-blot analysis of the mitochondrial DNA (mtDNA) indicates recombination events around a number of genes; however, the appearance of the CMS character is tightly correlated to reorganization around theatp6 gene, suggesting recombination downstream from theatp6 gene is involved in CMS. The nucleotide sequence downstream fromatp6 contains a pseudogene which was probably created by recombination of the mitochondrial genome. Sense and antisense transcripts of the downstream region ofatp6 were found in CMS-and restored CMS (fertile)-lines, but not in the normal (fertile) line. In the CMS line, several antisense transcripts of theatp6 gene were also found. However, in the restored line which contains a nuclear-encoded gene,Rf-1, the levels of these transcripts were lower than in the CMS line. These results suggest abnormal transcripts of theatp6 gene produced in the antisense direction may be involved in CMS, and that products of the nuclear-encoded restorer gene may reduce abnormal transcription in this region of the mitochondrial genome.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    ISSN: 1432-0983
    Keywords: DNA fingerprinting of Trichoderma ; Trichoderma reesei ; RFLP ; Strain classification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have analyzed nine different species of the filamentous fungus Trichoderma and three strains of T. reesei for the presence of hypervariable loci in their genomes by hybridization with simple repeat oligonucleotides [(CT)8, (GTG)5, and (GACA)4]. On the basis of the DNA-fingerprints obtained, the Trichoderma aggregate is re-classified into five groups: I (T. reesei, T. todica), II (T. polysporum, T. longibrachiatum, T. koningii, and T. pseudokoningii), III (T. virgatum), IV (T. saturnisporum) and V (T. harzianum). These results contradict the claim that T. reesei is a subspecies of T. longibrachiatum. Furthermore, hybridization with (CA)8 allowed a subdivision of group II, wherein T. pseudokoningii formed a subgroup, IIb, which is highly homologous with, but distinct from subgroup IIa. The results show that RFLP analysis may be used to re-classify the Trichoderma aggregate.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    ISSN: 1432-0983
    Keywords: Nuclear-cytoplasmic interactions ; Mitochondrial genome ; Chondriome variability ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Although the mitochondrial genomes of the Chinese Spring and Aquila varieties of wheat are normaly similar in organization, this is not so in tissue cultures initiated from their immature embryos where the mitochondrial genomes of both are rearranged and in different, characteristic, ways. However, the mitochondrial genomes of tissue cultures of reciprocal F1 crosses between these varieties were almost identical to one another, showing that nuclear genes control the rearrangement processes. These rearrangements are either due to the appearance of new structures or else result from changes in the relative amounts of subgenomic components. The severe reduction in the amount of certain molecular configurations in tissue cultures from reciprocal crosses is probably due to the presence of dominant information in the Aquila nuclear genome. Data obtained from tissue cultures initiated from F2 embryos of the cross Aquila x Chinese Spring suggest that at least two complementary genes are involved in this control. In contrast, the presence of new molecular arrangements appears to be under the control of a dominant allelic form of a Chinese Spring gene or genes. Thus, this study demonstrates that at least two sets of nuclear genes control the reorganization of the mitochondrial genome which occurs when tissue cultures are initiated from the immature embryos of wheat.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    ISSN: 1573-1561
    Keywords: Allelochemicals ; no-tillage ; conventional-tillage ; soils ; wheat ; Triticum aestivum ; mass spectrometry ; Petri-dish bioassay ; fatty acids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Putative allelochemicals found in the soil of no-tillage and conventional-tillage wheat plots near Stillwater, Oklahoma, were obtained by a mild alkaline aqueous extraction procedure, bioassayed to determine their biological activity, purified, and analyzed with a capillary gas chromatography-mass spectrometry-data analysis system. The most significant inhibition was found in bioassays of extracts from soil collected immediately after harvest in June, July, and August. No-tillage soils produced significant inhibition during the rest of the year also. Mass spectrometry showed fatty acids as the most abundant compounds. However, when bioassayed authentic samples of the five free fatty acids showed no significant biological activity toward wheat.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 16 (1990), S. 1927-1940 
    ISSN: 1573-1561
    Keywords: Allelopathy ; phytotoxic ; allelochemical ; α-bisabolol ; δ-cadinene ; p-cymen-9-ol ; essential oil ; germination ; phenethyl alcohol ; piperitenone ; vanillin ; Gossypium hirsutum ; Proboscidea louisianica ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The potential allelopathic activity of devil's-claw [Proboscidea louisianica (Mill.) Thellung] essential oil and a few of the compounds it contains on the elongation of cotton (Gossypium hirsutum L.) and wheat (Triticum aestivum L.) radicles was studied using a Petri dish bioassay. Essential oil was collected by steam distillation using an all-glass-Teflon assembly. Ether extracts of the steam distillates from fresh devil's-claw were inhibitory to cotton and wheat radicle elongation. The following six components of devil's-claw essential oil identified by CGC-MS-DS were inhibitory to cotton and/or wheat at a concentration of 1 mM: vanillin, piperitenone, δ-cadinene,p-cymen-9-ol, α-bisabolol, and phenethyl alcohol.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    ISSN: 1573-1561
    Keywords: Cover crops ; wheat ; Triticum aestivum ; soybean ; Glycine max ; soil extracts ; germination bioassays ; phenolic acids ; hydroxamic acids ; allelopathy ; slope analysis ; ivy-leaved morning glory ; Ipomoea hederacea ; crimson clover ; Trifolium incarnalum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The primary objective of this research was to determine if soil extracts could be used directly in bioassays for the detection of allelopathic activity. Here we describe: (1) a way to estimate levels of allelopathic compounds in soil; (2) how pH, solute potential, and/or ion content of extracts may modify the action of allelopathic compounds on germination and radicle and hypocotyl length of crimson clover (Trifolium incarnatum L.) and ivyleaved morning glory (Ipomoea hederacea L. Jacquin.); and (3) how biological activity of soil extracts may be determined. A water-autoclave extraction procedure was chosen over the immediate-water and 5-hr EDTA extraction procedures, because the autoclave procedure was effective in extracting solution and reversibly bound ferulic acid as well as phenolic acids from wheat debris. The resulting soil extracts were used directly in germination bioassays. A mixture of phenolic acids similar to that obtained from wheat-no-till soils did not affect germination of clover or morning glory and radicle and hypocotyl length of morning glory. The mixture did, however, reduce radicle and hypocotyl length of clover. Individual phenolic acids also did not inhibit germination, but did reduce radicle and hypocotyl length of both species. 6-MBOA (6-methoxy-2,3-benzoxazolinone), a conversion product of 2-o-glucosyl-7-methoxy-1,4-benzoxazin-3-one, a hydroxamic acid in living wheat plants, inhibited germination and radicle and hypocotyl length of clover and morning glory. 6-MBOA, however, was not detected in wheat debris, stubble, or soil extracts. Total phenolic acids (FC) in extracts were determined with Folin and Ciocalteu's phenol reagent. Levels of FC in wheat-conventionaltill soil extracts were not related to germination or radicle and hypocotyl length of either species. Levels of FC in wheat-no-till soil extracts were also not related to germination of clover or morning glory, but were inversely related to radicle and hypocotyl length of clover and morning glory. FC values, solute potential, and acidity of wheat-no-till soil extracts appeared to be independent (additive) in action on clover radicle and hypocotyl length. Radicle and hypocotyl length of clover was inversely related to increasing FC and solute potential and directly related to decreasing acidity. Biological activity of extracts was determined best from slopes of radicle and hypocotyl length obtained from bioassays of extract dilutions. Thus, data derived from the water-autoclave extraction procedure, FC analysis, and slope analysis for extract activity in conjunction with data on extract pH and solute potential can be used to estimate allelopathic activity of wheat-no-till soils
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    ISSN: 1573-5028
    Keywords: carboxy-terminal processing ; glycosylation ; Hordeum vulgare L. ; Prx locus ; RFLP ; signal peptide ; targeting
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The major peroxidase of barley seed BP 1 was characterized. Previous studies showed a low carbohydrate content, low specific activity and tissue-specific expression, and suggested that this basic peroxidase could be particularly useful in the elucidation of the structure-function relationship and in the study of the biological roles of plant peroxidases (S.K. Rasmussen, K.G. Welinder and J. Hejgaard (1991) Plant Mol Biol 16: 317–327). A cDNA library was prepared from mRNA isolated from seeds 15 days after flowering. Full-length clones were obtained and showed 3′ end length variants, a G+C content of 69% in the translated region, a 90% G or C preference in the wobble position of the codons and a typical signal peptide sequence. N-terminal amino acid sequencing and sequence analysis of tryptic peptides verified 98% of the sequence of the mature BP 1 which contains 309 amino acid residues. BP 1 is the first characterized plant peroxidase which is not blocked by pyroglutamate. BP 1 polymorphism was observed. BP 1 is less than 50% identical to other plant peroxidases which, taken together with its developmentally dependent expression in the endosperm 15–20 days after flowering, suggests a unique biological role of this enzyme. The barley peroxidase is processed at the C-terminus and might be targeted to the vacuole. The single site of glycosylation is located near the C-terminus in the N-glycosylation sequon -Asn-Cys-Ser- in which Cys forms part of a disulphide bridge. The major glycan is a typical plant modified-type structure, Manα1-6(Xylβ1-2)Manβ1-4GlcNAcβ1-4(Fucα1-3)GlcNAc. The BP 1 gene was RFLP-mapped on barley chromosome 3, and we propose Prx5 as the name for this new peroxidase locus.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 21 (1993), S. 919-921 
    ISSN: 1573-5028
    Keywords: ARS-related element ; dispersed repeat ; genomic DNA sequence ; molecular evolution ; Secale cereale ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A Hind III-generated fragment of wheat embryo nuclear DNA has been cloned and sequenced. The cloned fragment corresponds to a 1241 bp long, moderately repeated (60 000 copies/genome) segment of the genomic DNA. The repeat is AT-rich (67%), contains an open reading frame for 151 amino acids and several nucleotide blocks resembling the consensus domain of autonomously replicating sequences. Southern blot hybridization analyses indicate that the repeat is scattered through the wheat genome. A sequence homologous to this repeat occurs also in rye embryo nuclear DNA where it shows the same dispersion pattern as that observed for the wheat repeat.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    ISSN: 1573-5028
    Keywords: gene duplication ; photosynthesis ; RFLP ; Southern blots
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A second locus (Lhb1B) encoding Photosystem II Type I chlorophyll a/b-binding (CAB) polypeptides was identified in Arabidopsis thaliana. This locus carries two genes in an inverted orientation. The predicted sequences of the polypeptides encoded by these two genes show substantial divergence in their amino termini relative to each other and to the proteins encoded by the three Lhb1 CAB genes previously characterized [10], but little divergence within the predicted primary structure of the mature protein. DNA probes derived from seven additional types of tomato CAB genes, encoding chlorophyll a/b-binding polypeptides of several antenna systems of the photosynthetic apparatus, were tested against A. thaliana. Each of these hybridized in Southern blots to unique DNA fragment(s), demonstrating the existence of each of these different types of CAB genes in the genome of A. thaliana. The number of genes encoding each CAB type in A. thaliana was estimated to be similar to that of tomato.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    ISSN: 1573-5028
    Keywords: bark storage protein ; gene clustering ; RFLP ; systemic response
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Two wound-inducible cDNAs from poplar leaves show sequence identity to vegetative storage proteins (VSP) that accumulate seasonally in poplar bark tissues. We have compared the genomic organization, cDNA sequences and expression of the genes encoding the wound-inducible cDNAs (win4) with that of a bark VSP (called bark storage protein, or BSP). There appear to be several win4 genes in the poplar genome which segregate as a single locus and are therefore likely to be clustered. The same is true of the BSP genes. The win4 locus is linked (map distance of 5 cM) to the BSP locus, consistent with a common evolutionary origin of the genes. A near full-length win4 cDNA shows 75% sequence identity to BSP cDNAs. Both win4 and BSP are systemically wound-inducible; win4 transcripts accumulate in leaves and stems, whereas BSP transcripts accumulate almost exclusively in stems. A phloem transport-dependent signaling mechanism appears to be involved in systemic win4 expression after wounding. In contrast to BSP gene expression, win4 genes are not expressed in response to short day conditions. The data indicate win4 and BSP genes are differentially regulated, and their products may play important roles in the storage and reallocation of nitrogen in perennial plants.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 21 (1993), S. 99-108 
    ISSN: 1573-5028
    Keywords: fusion protein ; Oenothera ; plastome ; RFLP ; unidentified open reading frame
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The chloroplast DNA encodes genes for components of photosynthesis and the transcription-translation machinery; a number of unidentified open reading frames (ORFs) are also present. To determine whether a large ORF in the inverted repeat of chloroplast DNA of tobacco (ORF2280) encodes a chloroplast protein, a conserved region of the ORF was expressed in Escherichia coli. An antibody against the ORF protein was prepared using the purified fusion protein as an antigen. When incubated with proteins from the soluble fraction of tobacco, spinach and Oenothera chloroplasts, the antiserum detects relatively labile polypeptides, which have apparent molecular weights of 170 to 180 kDa. The ORF in tobacco and spinach is large enough to encode a protein of 240–250 kDa, thus it is possible that post-transcriptional or post-translational processing reduces the size of the expression product. Analysis of Oenothera chloroplasts representing four different plastome types revealed endonuclease restriction fragment length polymorphisms in chloroplast DNA indicative of insertion/deletion events in a region of the chloroplast DNA that shared significant sequence similarity with ORF2280. The ORF2280 antiserum was used to demonstrate that there are qualitative differences in the ORF proteins from different Oenothera plastome types.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Electronic Resource
    Electronic Resource
    Springer
    Biochemical genetics 31 (1993), S. 75-86 
    ISSN: 1573-4927
    Keywords: Triticum aestivum ; Wx protein ; two-dimensional polyacrylamide gel electrophoresis ; Wx locus ; waxy mutant
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Nullisomic analysis of waxy (Wx) protein of hexaploid wheat (Triticum aestivum L.) cv. “Chinese Spring” using two-dimensional polyacrylamide gel electrophoresis revealed that threeWx loci,Wx-A1, Wx-B1, andWx-D1, located on chromosome arms 7AS, 4AL, and 7DS, produce three distinct Wx subunit groups, subunit group-A (SGA), SGB, and SGD, respectively. SGA has a higher molecular weight and a more basic isoelectric point (pI) than the other two. SGB and SGD have the same molecular weight but a slightly different pI range. Owing to the detection of these three subunit groups, we were able to identify the expression of three waxy genes in wheat endosperm and to find two types of mutants among Japanese wheat cultivars, one lacking SGA and the others SGB. These results suggest the possibility of breeding a waxy wheat.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    ISSN: 1573-5028
    Keywords: retrotransposon ; Pisum ; segregation ; PCR ; RFLP ; mapping
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A DNA sequence between two legumin genes in Pisum is a member of the copia-like class of retrotransposons and represents one member of a polymorphic and heterogeneous dispersed repeated sequence family in Pisum. This sequence can be exploited in genetic studies either by RFLP analysis where several markers can be scored together, or the segregation of individual elements can be followed after PCR amplification of specific members.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 18 (1992), S. 603-605 
    ISSN: 1573-5028
    Keywords: ARS-related DNA repeat ; DNA sequence ; Secale cereale ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A 371 base pair segment (bordered by Hind III and Eco RI cutting sites) of wheat embryo nuclear DNA has been cloned and sequenced. It is AT-rich (68%), shares some sequence features with autonomously replicating sequence (ARS) elements, and occurs in approximately 7600 copies per haploid genome. When used as probe for blot hybridization to Hind III-digested wheat DNA, it gives an irregular series of hybridization bands. Essentially the same hybridization pattern was observed for rye DNA. It is concluded that this segment is distributed irregularly but, apparently, according to the same rule in both wheat and rye genomes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    ISSN: 1573-5028
    Keywords: wheat ; Triticum aestivum ; cDNA clone ; ADP-glucose pyrophosphorylase ; small-subunit ; starch
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A full-length cDNA clone from hexaploid bread wheat, encoding the small subunit of ADP-glucose pyrophosphorylase, has been isolated from an endosperm cDNA library. The cDNA insert has an open reading frame which encodes a protein of 473 amino acids (52.1 kDa). The presence of a chloroplast/amyloplast transit peptide of 22 amino acids is proposed. The deduced amino acid sequence exhibits a high degree of homology with the small subunit ADP-glucose pyrophosphorylase proteins from rice (with 90% of identical amino acids) and potato (with 86% of identical amino acids) and contains conserved sequence elements which are thought to represent the substrate binding and allosteric activator sites. The genes are organised as single-copy loci on chromosomes 7A, 7B and 7D in the wheat genome and are highly expressed during grain development. Homologous transcripts are expressed in leaves and roots.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 26 (1994), S. 1065-1071 
    ISSN: 1573-5028
    Keywords: Brassica ; polyploid ; gene expression ; RT-PCR ; RFLP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract One of the essential issues regarding evolution of polyploid species is how duplicate genes are expressed. Most studies on gene expression in polyploids have been based on isozyme analyses; RNA analysis has not been widely used partially due to difficulties in distinguishing homologous transcripts which usually have the same length and similar or almost identical sequences. In this study, a method combining RT-PCR with RFLP was used to analyze transcripts of homologous genes in natural and synthetic Brassica amphidiploids. Sequences coding for several known genes were selected and used to synthesize gene-specific primers. Total RNAs were used as templates for RT-PCR to amplify homologous transcripts in three diploid parental species, three cultivated amphidiploid species and six synthetic amphidiploids. For each gene, initial PCR products amplified in all species had identical length; however, homologous transcripts in the diploid and amphidiploid species could be distinguished after digesting the PCR products with restriction enzymes. Preliminary results based on three genes indicated that both transcripts from the diploid parents were expressed in the synthetic and natural amphidiploids. This study represents the first application of RT-PCR and RFLP analysis to investigate expression of homologous genes in higher plants. The technique is a sensitive, simple and efficient method for distinguishing homologous transcripts in a mixed RNA population and can be applied to many types of studies on expression of homologous genes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    ISSN: 1573-5028
    Keywords: Calvin cycle genes ; gene expression ; SBPase ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We report here the isolation and nucleotide sequence of genomic clones encoding the chloroplast enzyme sedoheptulose-1,7-bisphosphatase (SBPase) from Arabidopsis thaliana. The coding region of this gene contains eight exons (72–76 bp) and seven introns (75–91 bp) and encodes a polypeptide of 393 amino acids. Unusually, the 5′ non-coding region contains two additional AUG codons upstream of the translation initiation codon. A comparison of the deduced Arabidopsis and wheat SBPase polypeptide sequences reveals 78.6%, identity. Expression studies showed that the level of SBPase mRNA in Arabidopsis and wheat is regulated in a light-dependent manner and is also influenced by the developmental stage of the leaf. Although the Arabidopsis SBPase gene is present in a single copy, two hybridizing transcripts were detected in some tissues, suggesting the presence of alternate transcription start sites in the upstream region.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 16 (1991), S. 831-839 
    ISSN: 1573-5028
    Keywords: RFLP ; Oryza ; rice ; genome evolution ; allotetraploid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Restriction fragment length polymorphisms (RFLPs) were studied in fourteen accessions of CCDD genome allotetraploid wild rice species (Oryza latifolia, O. alta and O. grandiglumis). Fourteen nuclear RFLP markers previously mapped in AA genome-cultivated rice were used as probes. A phylogenetic tree, constructed by parsimony analysis based on RFLPs, grouped the accessions according to their geographic origin from Central or South America. Oryza alta, O. grandiglumis and one accession of O. latifolia grouped together as a subgroup, and our results suggested that the three taxa should be considered as populations of a single complex species. Duplicate loci, representing the two constituent genomes of the allotetraploid, were observed for most RFLP markers. By comparing RFLPs from the allotetraploids with those from a CC genome diploid wild species (O. officinalis), it was possible to detect RFLPs specific for both the CC and DD genomes of the allotetraploid. In inter-accession F2 populations, independent segregation of RFLP markers for CC and DD genomes was observed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    ISSN: 1573-5028
    Keywords: chromosome assignment ; dihaploid progenies ; heterozygosity ; potato ; rDNA ; RFLP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Restriction map and organization of rDNA was inferred from analysis of dihaploid progenies of two tetraploid genotypes of cultivated potato. Each tetraploid genotype was characterized by a specific distribution of different types of rDNA repetition units on their four homologous chromosomesII. The genotypes were heterozygous and differed by the kind of units carried by each chromosomeII. Models for the generation of the observed organization are discussed and supported by first cloning studies.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    ISSN: 1573-5028
    Keywords: cDNA ; cyanogenesis ; β-glucosidase ; RFLP ; Trifolium repens
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The Li locus in white clover controls the presence of cyanogenic β-glucosidase (linamarase) activity in leaf tissue, such that plants homozygous for the ‘null’ allele (li) have no linamarase activity in this tissue. The isolation of a cDNA clone from linamarase mRNA is described. The cDNA clone is used to further characterise alleles of the Li locus. Northern blot analysis shows that plants homozygous for the ‘null’ allele (li li) produce very reduced levels of mRNA which hybridises to the cDNA. Heterozygous plants (Li li), which have intermediate levels of enzyme activity, produce intermediate levels of mRNA. Southern blot analysis of Hind III digested genomic DNA shows that the white clover genome contains three genes with homology to the linamarase cDNA and that at least two of these genes segregate independently. Analysis of the cosegregation of linamarase activity and the presence of genomic restriction fragments identifies the genomic sequence specifying linamarase structure and indicates either a structural or cis acting control function of the Li locus.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 15 (1990), S. 947-950 
    ISSN: 1573-5028
    Keywords: clpP gene ; rps12 gene ; ribosomal protein S12 ; intron ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    ISSN: 1573-5028
    Keywords: chloroplast genes ; cytochrome b6 ; introns ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 16 (1991), S. 1099-1101 
    ISSN: 1573-5028
    Keywords: wheat ; Triticum aestivum ; cDNA clone ; waxy protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 18 (1992), S. 1207-1208 
    ISSN: 1573-5028
    Keywords: Triticum aestivum ; nuclear tRNATyr gene ; DNA sequence ; transcription ; processing ; splicing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 22 (1993), S. 437-446 
    ISSN: 1573-5028
    Keywords: RFLP ; genome ; PFGE ; multicopy markers ; symbiosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Pulsed-field gel electrophoresis (PFGE) was used to study a cluster of molecular markers in the soybean genome. There were 550 kb per centimorgan (cM) in the cluster, which is close to the calculated average for the whole genome. The analysis was complicated by the presence of duplicated sequences, and some ambiguities arising from this were resolved by using second-dimension conventional electrophoresis to relate physical maps to the RFLP map of soybean. The results show that there is a high degree of conservation of ‘rare cutter’ sites between homoeologous regions. Finally, PFGE can confirm physical linkage of monomorphic copies of markers, which can aid in the study and comparison of homoeologous regions that are invisible to RFLP analysis.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    ISSN: 1573-5028
    Keywords: rRNA ; PCR ; ITS ; DNA sequence ; nucleotide ; Triticum aestivum ; wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    ISSN: 1573-5028
    Keywords: mitochondrial DNA ; repeated sequences ; ribosomal RNA ; t-elements ; Triticum aestivum ; wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We report the sequence of a 7.2 kilobase pair DNA fragment containing a copy of the wheat mitochondrial gene (rrn26) that encodes the mitochondrial large-subunit ribosomal RNA (26S rRNA). The mature 26S rRNA was determined by direct RNA sequencing to be 3467 nucleotides long, and to share a 5′-terminal pentanucleotide (5′-AUCAU), thought to be important in post-transcriptional processing, with the wheat mitochondrial small-subunit (18S) rRNA. Two other prominent features of the sequence were noted. First, upstream of rrn26 are located two tandem copies of a 70 base pair element containing a putative mitochondrial promoter motif (TCGTATAAAAA). Second, downstream of rrn26 is a sequence element that, if transcribed, would produce and RNA with a secondary structure resembling that of tRNAs but differing sufficiently from the latter structure to preclude any transcript from functioning normally in translation. These upstream and downstream sequence elements may play a role in the expression of rrn26 in wheat mitochondria.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    ISSN: 1573-5028
    Keywords: mitochondria ; nad6 ; NADH-ubiquinone reductase ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A region of the mitochondrial (mt) DNA of wheat was studied because of its homology with other plant mtDNAs. Sequence analysis revealed an open reading frame encoding a polypeptide of 247 amino acids. Comparison of the sequence of the putative polypeptide with the protein sequence data of the Swiss-Prot library reveals homology with subunit 6 of the NADH-ubiquinone complex of mitochondria from Marchantia polymorpha, Podospora anserina, Chlamydomonas reinhardtii and of chloroplasts from M. polymorpha and Oryza sativa. No similarity was detected when compared with the subunit 6 of animal mitochondria, probably due to the rapid evolution of the sequence. A single 1.2 kb transcript appears in northern RNA blots. We found 15 edited sites of which only 13 give amino acid changes. This is the first report of a mt nad6 gene in higher plants.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    Electronic Resource
    Electronic Resource
    Springer
    Plant cell reports 9 (1990), S. 14-16 
    ISSN: 1432-203X
    Keywords: Triticum aestivum ; Anther culture ; Sugars ; Wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The effect of employing different sugars in wheat anther culture has been investigated using four Spring wheat cultivars. The most responsive cultivar, Orofen, gave a three to four-fold increase in embryo yield when maltose was used in place of sucrose, with 50 embryos being produced for every 100 anthers cultured. Measurement of sugar concentrations in the culture media indicated that sucrose was more rapidly hydrolysed than maltose. However, neither the osmotic potential of the medium nor the concentration of glucose appeared to be critical factors in determining embryo yield.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 79 (1990), S. 401-410 
    ISSN: 1432-2242
    Keywords: Puccinia graminis tritici ; Puccinia recondita Tritici ; Triticum aestivum ; Rust resistance ; Gene identification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Genes for resistance toPuccinia graminis tritici andPuccinia recondita tritici identified in four South African wheats were:Sr6,Sr8a,Sr9e, andLr13 in ‘W3762’;Sr5,Sr8a,Sr9b,Sr12,Sr24,Lr13, andLr24 in ‘W3760’;Sr2,Sr24,SrC,Lr13, andLr24 in ‘W3751’; andSr7a,Sr23,Sr36, andLr16 in ‘W3755’. GenesSr2,Sr9e, andSr24 also conferred adult plant resistance to the predominant pathotypes ofP. graminis tritici. GenesSr7a,Sr23, andSrC, when present alone, did not confer acceptable adult plant resistance, even though low seedling reactions were associated with them when tested with the same pathotypes. Genetic recombination betweenLr13 andSr9e was estimated at 12.5%±2.3%.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 79 (1990), S. 577-582 
    ISSN: 1432-2242
    Keywords: Genetic marker ; RFLP ; Quantitative traits
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Digestion of genomic DNA with the restriction endonuclease Avail disclosed a probable insertion deletion of approximately 200 base pairs (bp) near the prolactin gene. Two alleles were apparent as three distinct hybridization patterns. These alleles were statistically associated with quantitative trait loci among sons of one elite Holstein sire family. The favorable genotype was correlated with the presence of a 1.15-kb hybridization band inherited from the sire when genomic DNA was probed with a full-length cDNA for prolactin. Pedigree estimates of genetic merit among genotypes were similar, differing by only 19.3 kg for milk in ancestor merit. Comparisons of genetic estimates for quantitative yield traits in offspring of this heterozygous sire showed significant (P〈0.05) differences between homozygous genotypes for predicted difference milk (PDM), predicted difference dollars (PD$), cheese yield dollars, and protein dollars. The estimated differences between homozygous genotypes for USDA Transmitting Abilities of PDM, PD$, Cheese Yield $ and Protein $ were 282.93 kg, $74.35, $48.58 and $53.67, respectively. However, the estimated breeding values from progeny ranged over 900 kg in transmitting ability for milk. Frequency of the favorable marker allele was estimated to be 0.231 in the elite cow population used as dams of sons. These results demonstrate the potential of molecular biological techniques to discriminate between individuals within a family and to predict breeding values for selection schemes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 79 (1990), S. 77-80 
    ISSN: 1432-2242
    Keywords: Triticum aestivum ; Anther culture ; 1B/1R translocation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The in vitro microspore androgenesis reaction of 25 commercial German spring (including 4 Triticum durum) and 50 winter wheat cultivars was investigated. Tremendous genotypical differences were found in microspore response. The best-responding winter wheat cultivai, “Florida”, is characterized by the presence of a 1B/1R wheat-rye translocation chromosome. The significance of this finding and other genetic systems for future use of haploids in plant breeding is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 80 (1990), S. 673-679 
    ISSN: 1432-2242
    Keywords: Rice ; Tissue culture ; Somaclonal variation ; RFLP ; Methylation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Regenerants of rice were examined by RFLP analysis to determine the occurrence and extent of somaclonal variation. DNA polymorphisms were observed both among plants regenerated from different callus cultures as well as among sibling plants derived from a single callus. Regardless of the basal medium, a higher degree of genetic instability was found among plants regenerated from callus cultures maintained for longer incubation periods (67 days) than among those from shorter incubation periods (28 days). Detailed analysis showed that in several regenerants, there was a close correlation among those plants exhibiting DNA rearrangements and those with apparent methylation changes. Such alterations were observed with both structural and housekeeping genes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 80 (1990), S. 680-686 
    ISSN: 1432-2242
    Keywords: Retrotransposon ; Zea ; RFLP ; Bs1 ; Transposable element
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Thirty-eight accessions from Zea and 20 accessions from related genera were probed for the presence of Bs1, a retrotransposon originally found in maize. All maize and teosinte plants tested show the presence of Bs1 in one to five densely hybridizing bands. The mean copy numbers of Bs1 elements among the maize and teosinte accessions were similar: 2.92 and 3.25, respectively, with no large differences between any subgroups. Most exotic maize samples exhibited two common bands of 7.8 kb and 4.7 kb. Section Zea teosintes (but not teosintes of section Luxuriantes) also show the presence of a common band of the same size as the smaller common band in maize. At reduced stringency, Tripsacum dactyloides exhibited a single hybridizing band at 6.9 kb. Results argue for the evolution of maize from a mexicana or parviglumis teosinte, and the evolution of the Bs1 element within the tribe Andropogoneae. Additionally, recombinant inbred lines were probed for the presence of Bs1, in order to map the chromosomal locations of Bs1 elements in four different maize lines. Two of the recombinant inbred parental lines had an element (Bs1-F) on chromosome 5, while the other two lines had an element (Bs1-S) on chromosome 8. Restriction site polymorphisms have apparently arisen in the vicinity of Bs1-S since its insertion. Segregation analysis of other lines was also performed; the data indicate that Bs1 has the distribution expected of a transposable element, different locations in different lines, and not that of a fixed gene locus. However, the common bands in the Zea mays lines and the recombinant inbred data imply that Bs1 is not highly mobile.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    ISSN: 1432-2242
    Keywords: Preferential transmission ; Triticum aestivum ; Aegilops sharonensis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The transmission of chromosome 4S l from Aegilops sharonensis was observed in a range of wheat genetic backgrounds. Chromosome 4S l was transmitted at a very high frequency (at least 97.8%) in all crosses. The genetic background appears to only have a small effect on transmission. The frequency of transmission of chromosome 4S l was the same in each genetic background through both the male and female gametes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 81 (1991), S. 576-580 
    ISSN: 1432-2242
    Keywords: Pollen culture ; Pollen maturation ; Pollination ; Triticum aestivum ; Gliadins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Immature pollen of two varieties of Triticum aestivum, at the stage right after the first pollen mitosis, was isolated from individual anthers and cultured in microcultures of microliter droplets. In a specifically designed medium, some of the pollen grains developed to maturity. These were applied to excised stigmas on agar, where they produced pollen tubes. Application to flowers in vivo led to seed set. Pollen was matured in vitro from a variety that produced a different protein banding pattern on SDS-PAGE as compared to the variety that was pollinated. The protein banding in the produced seeds showed the hybrid pattern, demonstrating that the seeds were not produced by self-pollination in this in-breeding species but by pollination with the in-vitro-matured pollen.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 82 (1991), S. 393-398 
    ISSN: 1432-2242
    Keywords: Maize ; Helminthosporium turcicum race1 ; RFLP ; NILs ; Mapping
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have identified tight linkage of an RFLP marker to theHt1 gene of maize that confers resistance to the fungal pathogenHelminthosporium turcicum race 1. This was accomplished by the use of four pairs of near isogenic lines (NILs; B73, A619, W153R, and CM105), each differing by the presence or the absence of the geneHt1. SinceHt1 maps to chromosome 2, 26 clones already mapped to this chromosome were labeled and probed against Southern blots of these NILs DNA digested with three restriction enzymes:EcoRI,BamHI, andHindIII. Six markers exhibited an RFLP for at least one pair of NILs. Presumptive linkage was further tested by analyzing the segregation of five of the six markers (one was monomorphic in the cross studied) and resistance toH. turcicum race 1 on 95 F2 individuals from the cross DF20 × LH146Ht. The results indicate a tight linkage between one of the DNA markers,UMC150B, and theHt1 gene.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 82 (1991), S. 615-620 
    ISSN: 1432-2242
    Keywords: HSP-70 ; BiP/GRP-78 ; Wheat ; Triticum aestivum ; Chaperone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Animal and plant cells contain a family of constitutively expressed HSP-70 cognate proteins that are localized in different subcellular locations and are presumed to play a role in protein folding and transport. Utilizing antibodies raised against the yeast endoplasmicreticulum-localized HSP-70 cognate termed BiP/GRP-78, as well as antibodies raised against the Escherichia coli HSP-70 protein DnaK, we have identified and characterized a large family of closely related proteins in wheat. One protein band of 78 kDa that is apparently closely related to yeast BiP was localized in the endoplasmic reticulum. This band cross-reacted with the yeast BiP but not with the DnaK-specific antibodies. The yeast BiP antibodies also recognized a cytoplasmic protein of 70 kDa that is probably related to the HSC-70 cognate proteins. These two proteins were further confirmed as HSP-70 cognates by their ability to bind to an ATP-agarose column. Probing of proteins from purified wheat mitochondrial preparations with the yeast BiP and DnaK-specific antibodies showed that this organelle contained a family of HSP-70-related proteins. The yeast BiP antibodies recognized two mitochondrial proteins of 60 and 58 kDa, but failed to detect any protein in the size rang of 70 to 80 kDa. However, the presence of immunologically distinct proteins of 90 and 78 kDa, as well as of lower molecular weight from this family in the mitochondria, was shown by probing with the DnaK-specific antibodies. A new protein of 30 kDa, cross-reacting with anti-yeast BiP antibodies, was detected only in developing seeds, close to their maturity. The evolution of HSP-70 cognate proteins in wheat as shown in this study is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 82 (1991), S. 697-703 
    ISSN: 1432-2242
    Keywords: RFLP ; Bamboo ; Phyllostachys ; Chloroplast DNA ; Germplasm screening
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Bamboo species are difficult to identify because flowering material is seldom available and taxonomy is of necessity based on vegetative characters. To evaluate the utility of restriction fragment length polymorphism (RFLP) analysis in bamboo systematics and germplasm screening, a library of random genomic probes from a Phyllostachys nigra PstI library was constructed. Probes from the library were used to screen bamboo germplasm consisting mostly of temperate bamboos of the genus Phyllostachys. RFLP variation was abundant, and species-specific patterns were readily obtained. Chloroplast DNA showed little variation among the bamboo accessions analyzed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    ISSN: 1432-2242
    Keywords: RFLP ; PCR ; Rice ; Inheritance ; Nonradioactive
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Thirty mapped Indica rice genomic (RG) clones were partially sequenced from each end. From such sequence data, pairs of oligonucleotides were synthesized to act as primers for polymerase chain reaction (PCR) amplification of the corresponding loci in crude total DNA preparations. The PCR products from DNA of Indica varieties were of the sizes expected from the sizes of the corresponding RG clones. However, size polymorphisms were seen between PCR products from Indica and Japonica varieties, and among wildOryza species. Restriction fragment length polymorphism (RFLP) was observed between PCR products of Indica varieties simply by electrophoretic analysis of restricted products, without the need for Southern hybridization or radiolabelling. The RFLPs noted between varieties ARC6650 and Phalguna were inherited in recombinant inbred lines derived from a cross between them. The RFLPs were detectable in PCR products amplified from DNA extracted by a simple procedure from single seedlings or leaves, and revealed genetic heterogeneity in cultivated lines. An approach is described that is relevant to the acceleration of classical plant breeding through molecular techniques.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 82 (1991), S. 674-680 
    ISSN: 1432-2242
    Keywords: Puccinia recondita tritici ; Triticum aestivum ; Rust resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A study of spring bread wheat (Triticum aestivum) germ plasm developed at the International Maize and Wheat Improvement Center (CIMMYT) showed highly significant phenotypic variability for each component of partial resistance (namely, uredial appearance period, latency period, uredial number and uredial size) to Puccinia recondita f. sp. tritici. All of the wheat genotypes displayed longer uredial appearance and latency periods and decreased uredial number and uredial size when compared to the susceptible check cultivar ‘Morocco’. Positive correlations between uredial appearance period and latency period, and uredial number and uredial size, and negative correlations between uredial appearance and latency periods and uredial number and uredial size, inclusive, suggested that the components of partial resistance were either tightly linked or under pleiotropic genetic control. Compared to ‘Morocco’, all entries had slow disease progress in the field and variation occurred in the germ plasm for the area under the leaf rust progress curve. Disease progress was negatively correlated with uredial appearance and latency periods, whereas a positive correlation was observed with uredial number and uredial size. Certain genotypes displayed high levels of partial resistance resulting in low disease incidence in the field.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 83 (1991), S. 89-96 
    ISSN: 1432-2242
    Keywords: RFLP ; Alfalfa ; Genetic diversity ; Phylogenetic tree ; Gene duplication
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Alfalfa (Medicago sativa L.) is a major forage crop throughout the world. Although alfalfa has many desirable traits, continued breeding is required to incorporate pest resistances and other traits. We conducted this study to determine the amount of restriction fragment length polymorphism (RFLP) variability present within and between diploid and tetraploid alfalfa populations, and whether or not this variability is sufficient for construction of an RFLP map. Diploid plants from M. sativa ssp. falcata, ssp. coerulea, and ssp. sativa and tetraploid spp. sativa cultivars ‘Apollo,’ ‘Florida 77,’ and ‘Spredor 2’ were included. A total of 19 cDNA clones was probed onto genomic Southern blots containing DNA digested by EcoRI, HindIII, or BamHI. Phylogenetic trees were produced, based on parsimony analysis of shared restriction fragments. Evidence for extensive gene duplication was found; most probes detected complex patterns of restriction fragments. Large amounts of variation are present within all diploid subspecies. M. sativa ssp. falcata plants formed clusters distinct from ssp. sativa or ssp. coerulea plants, which were not distinctly clustered. Some M. sativa ssp. falcata plants were more similar to the other groups than to other plants within ssp. falcata. Variation among tetraploid cultivars showed that Florida 77 and Apollo had more similarities than either showed with Spredor 2. All three cultivars showed large within-population variation, with Apollo being the most diverse and Spredor 2 the least. Based on these results, development of an RFLP map at the diploid level appears possible. Also, differentiation of cultivars, particularly ones of divergent origin, seems possible based on RFLP patterns.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 83 (1992), S. 428-434 
    ISSN: 1432-2242
    Keywords: ‘Null’ forms ; RFLP ; Gliadins ; LMW glutenins ; Deletion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Wheat accessions lacking some of the ω- and γ-gliadin components encoded by the Gli-1 loci on the short arm of chromosome 1D in bread wheat and chromosome 1A in durum wheat were studied by two-dimensional polyacrylamide gel electrophoresis and restriction fragment analysis. Digested genomic DNAs of ‘normal’ and ‘null’ forms were probed with a cDNA clone related to ω-/γ-gliadins and with a genomic clone encoding an LMW subunit of glutenin. The hybridisation patterns with the ω-/γ-gliadin probe were similar to those of cvs ‘Chinese Spring’ and ‘Langdon’ used as standards for bread and durum wheats, respectively, but several restriction fragments located on the 1D chromosome of bread wheat and the 1A chromosome of durum wheat were absent in the ‘null’ forms. In addition, specific LMW glutenin fragments encoded by the same chromosomes were also absent in the ‘null’ forms, suggesting that simultaneous deletions of blocks of genes for both ω-/γ-gliadins and LMW glutenins had occurred. Comparisons of the protein and RFLP patterns enabled some proteins to be mapped to specific restriction fragments.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 83 (1992), S. 895-902 
    ISSN: 1432-2242
    Keywords: Finger millet ; Eleusine ; rDNA ; RFLP ; Grasses
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Finger millet is an important cereal crop in the semi-arid regions of Africa and India. The crop belongs to the grass genus Eleusine, which includes nine annual and perennial species native to Africa except for the New World species E. tristachya. Ribosomal DNA (rDNA) variation in finger millet and related wild species was used to provide information on the origin of the genomes of this tetraploid crop and point out genetic relationships of the crop to other species in the genus. The restriction endonucleases used revealed a lack of variability in the rDNA spacer region in domesticated finger millet. All the rDNA variants of the crop were found in the proposed direct tetraploid ancestor, E. coracana subsp. africana. Wild and domesticated finger millet displayed the phenotypes found in diploid E. indica. Diploid Eleusine tristachya showed some similarity to the crop in some restriction sites. The remaining species were quite distinct in rDNA fragment patterns. The study supports the direct origin of finger millet from subspecies africana shows E. indica to be one of the genome donors of the crop, and demonstrates that none of the other species examined could have donated the second genome of the crop. The rDNA data raise the possibility that wild and domesticated finger millet could have originated as infraspecific polyploid hybrids from different varieties of E. indica.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 84 (1992), S. 39-48 
    ISSN: 1432-2242
    Keywords: Genetic map ; Molecular markers ; RFLP ; Fruit breeding ; Citrus spp.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Genetic linkage analysis was performed using two segregating populations of citrus. One population arose from an intergeneric backcross of Citrus grandis (L.) Osb. cv ‘Thong Dee’ and Poncirus trifoliata (L.) Raf. cv ‘Pomeroy’, using the former as the recurrent (female) parent. The other population came from an interspecific backcross of C. reticulata Blanco cv ‘Clementine’ and C. x paradisi Macf. cv ‘Duncan’, using the former as the recurrent (male) parent. A total of 11 isozyme and 58 restriction fragment length polymorphisms were found to segregate in a monogenic fashion in one or both populations. Linkage analysis revealed that 62 of the loci examined mapped to 11 linkage groups, while 7 loci segregated independently from all other markers. Gene order was highly conserved between the maps generated from the two divergent segregating populations. Possible applications of the use of such maps in tree fruit breeding are discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 84 (1992), S. 113-117 
    ISSN: 1432-2242
    Keywords: Beet ; Somaclonal variation ; Isozyme ; RFLP ; Genetic stability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Sugar, fodder and garden beet (Beta vulgaris L.) plants have been regenerated in culture from a range of expiant material. Of the regenerants 764 were subjected to isozyme analysis using eight enzyme-specific stains, and 60 were subjected to RFLP analysis using three cDNA probes. Both molecular techniques allowed the identification of somaclonal variant plants. Assessment of the numbers of variant isozymes and restriction fragments has allowed the calculation of the approximate percentage of variant alleles occurring in any one somaclonal regenerant, namely between 0.05% and 0.1%.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 84 (1992), S. 286-290 
    ISSN: 1432-2242
    Keywords: Taxonomy ; Banana ; RFLP ; Musa ; Phylogeny
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Random genomic probes were used to detect RFLPs in 19 Musa species and subspecies. A total of 89 phylogenetically informative alleles were scored and analyzed cladistically and phenetically. Results were in general agreement with morphology-based phylogenetic analyses, with the following exceptions: our data unambiguously places M. boman in section Australimusa, and indicates M. beccarii is very closely related to M. acuminata. Additionally, no support was found for the separation of section Rhodochlamys from section Musa. A comparison of morphology-based and RFLP-based phylogenetic analyses is presented.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 84 (1992), S. 845-850 
    ISSN: 1432-2242
    Keywords: Flax ; Rust ; RFLP ; Genetic segregation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Random cDNA sequences synthesized from poly A+ RNA extracted from germinated urediospores of the flax rust fungus, Melampsora lini, were used as probes to detect restriction fragment length polymorphisms (RFLPs) in three races of M. lini originating from cultivated flax, Linum usitatissimum, and one race originating from Australian native flax, L. marginale. Fourteen out of 22 probes tested detected RFLPs in the three races from cultivated flax while 19 of the probes detected polymorphisms between these three races and the race from L. marginale. The segregation of seven RFLPs was determined in a family of 19 F2 progeny derived from a cross between two of the rust races. With six of these the inheritance was consistent, in each case, with the segregation of alleles at a single locus. Inheritance of the seventh was unusual and an explanation involving two loci with null alleles at each was proposed. No linkage was detected between any of the RFLP loci and nine unlinked loci specifying avirulence.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 84 (1992), S. 941-946 
    ISSN: 1432-2242
    Keywords: Triticum aestivum ; Genetic differences ; Heat-shock proteins ; Heat-shock response ; DNA polymorphism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Heat-shock protein (HSP) gene expression in two wheat lines cv ‘Mustang’ (heat-tolerant) and cv ‘Sturdy’ (heat-susceptible) were analyzed to determine if wheat genotypes differing in heat tolerance also differ in in-vitro HSP synthesis (translatable HSP mRNAs) and steady-state levels of HSP mRNA. Several sets of mRNA were isolated from seedling leaf tissues which had been heat-stressed at 37 °C for various time intervals. These mRNAs were hybridized with HSP cDNA or genomic DNA probes (HSP17, 26, 70, 98, and ubiquitin). Protein profiles were compared using in-vitro translation and 2-D gels. The Northern slot-blot data from the heat-stress treatment provide evidence that the heat-tolerant cv ‘Mustang’ synthesized low molecular weight (LMW) HSP mRNA earlier during exposure to heat shock and at a higher level than did the heat-susceptible cv ‘Sturdy’. This was especially true for the chloroplast-localized HSP. The protein profiles shown by 2-D gel analysis revealed that there were not only quantitative differences of individual HSPs between the two wheat lines, but also some unique HSPs which were only found in the ‘Mustang’ HSP profiles. The high level of RFLP between the two wheat lines was revealed by Southern blot hybridization utilizing a HSP17 probe. These data provide a molecular basis for further genetic analysis of the role of HSP genes in thermal tolerance in wheat.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 85 (1992), S. 73-78 
    ISSN: 1432-2242
    Keywords: Triticum aestivum ; Intergeneric gene transfer ; Allosyndetic recombination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The ‘Chinese Spring’ ph1b and ph2b mutants, as well as the nulli 5B tetra 5D stock were utilized in an attempt to effect homoeologous chromatin exchange between the ‘Indis’ chromosome translocation [derived from Thinopyrum distichum (Thunb.) Löve] and chromosome arm 7DL of common wheat. A homoeoallele of Lr19 and linked genes for yellow flour-pigmentation were utilized as markers. Seven selections with recombinations involving the foreign, translocated segment were recovered. Four of these had white endosperms and were leaf-rust resistant. The remaining lines were leaf-rust resistant and had levels of endosperm pigmentation intermediate to those of ‘Indis’ and ‘Chinese Spring’. The recombined translocation segments coding for white endosperm are no longer associated with chromosome 7D. The original translocated segment may, therefore, not be fully homoeologous to 7DL. The recombinants with white endosperm also lack the stem-rust resitance gene Sr25, but retained the segregation distorter locus, Sd-1. However, it seems as though an enhancer locus (or loci) of Sd-1 had been lost.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 85 (1992), S. 101-104 
    ISSN: 1432-2242
    Keywords: Marker assisted selection ; RFLP ; QTL ; Quantitative genetics ; Corn breeding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The objective of this paper is to present genetic theory demonstrating the conditions under which it should be possible to identify molecular marker-quantitative trait locus (QTL) associations in crosses of random-mating populations to inbreds. Using as an example the cross of a corn (Zea mays L.) population to an inbred, the expected disequilibrium for testcross and per se performance of F2, F3, BC1 (to the inbred) and recombinant inbred generations was derived for cases where a marker allele is linked to an unfavorable QTL allele in the inbred and where the marker allele is linked to a favorable QTL allele in the inbred. Disequilibrium in segregating generations was shown to be a function of disequilibrium in the parent population, the frequency of marker and QTL alleles in the parent population, and the recombination distance between the marker and the QTL. To maximize the opportunity to identify a favorable QTL the following procedures are suggested: (1) Select marker loci with alleles in the parent population which are not present in the inbred. (2) Select populations known to have favorable QTL alleles not present in the inbred. (3) Use as many marker loci as possible to enhance the probability of tight linkage between the marker and the QTL.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    ISSN: 1432-2242
    Keywords: Pea ; Pea seed-borne mosaic virus ; Disease resistance ; Genome mapping ; RFLP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The location of sbm-1 on the Pisum sativum genetic map was determined by linkage analysis with eight syntenic molecular markers. Analysis of the progeny of two crosses confirmed that sbm-1 is on chromosome 6 and permitted a more detailed map of this chromosome to be constructed. The inclusion of Fed-1 and Prx-3 among the markers facilitated the comparison of our map with the classical genetic map of pea. The sbm-1 gene is most closely linked to RFLP marker GS185, being separated by a distance of about 8 cM. To determine the practical value of GS185 as a marker for sbm-1 in plant breeding programs, the GS185 hybridization pattern and virus-resistance phenotype were compared in of a collection of breeding lines and cultivars. Three GS185 hybridization patterns were discerned among the lines. A strong association was found between one of these patterns and resistance to PSbMV.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 86 (1993), S. 181-188 
    ISSN: 1432-2242
    Keywords: Sugarcane ; Gramineae ; Tissue culture ; RFLP ; Molecular analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The genomic stability of tissue culture regenerants of sugarcane (Saccharum spp. hybrids, cvs ‘CP721210’, ‘CP68-1067’ and ‘B43-62’) was analyzed by DNA restriction fragment length polymorphism (RFLP). Plants regenerated from calli, cell suspensions, cryopreserved cell suspensions and protoplasts were used. Total DNA isolated from 19 different sources was digested with EcoRI, HindIII, BamHI, BamHI, EcoRI and PstI and probed with six known maize mitochondrial genes (coxI, coxII, atpA, atp6, atp9 and rrn18-rrn5), three random maize mitochondrial cosmid clones, two random maize chloroplast cosmid clones and a wheat Nor locus clone. Hybridization patterns indicated that the variation observed was minor and appeared only in the secondcycle regenerants. No differences were observed among the three cultivars and the regenerants from calli, suspension culture, cryopreserved suspension culture and protoplasts. Mitochondrial DNA (mtDNA) isolated from ‘CP72-1210’ plants and its embryogenic cell suspensions, and bulk samples from all ‘CP72-1210’ regenerants pooled together were digested with EcoRI, HindIII, PstI, BamHI and SalI and probed with three recombinationally active wheat mtDNA clones, K′, K3 and X2. No variation in the mtDNA restriction patterns was observed between the ‘CP72-1210’ plants and its regenerants. However, restriction pattern variation was observed only from EcoRI digestion, and hybridization patterns of K3, K′ and X2 revealed minor variations in the mtDNA of cell suspensions when compared with the DNA of the ‘CP72-1210’ plant. Except for a qualitative variation detected by the X2 probe and minor stoichiometric variations detected by the K3 probe, sugarcane DNAs were found to be stable after plant regeneration.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    ISSN: 1432-2242
    Keywords: Aegilops ventricosa ; DNA probes ; Introgression lines ; Addition lines ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Stable wheat-Aegilops introgression lines with 42 chromosomes (H-93), derived by repeated selfing from a cross (Triticum turgidum x Aegilops ventricosa) x T. aestivum, have been characterized using the following DNA probes and isozyme markers: (1) single or low-copy DNA fragments from Ae. ventricosa; (2) known cDNA probes corresponding to α1-thionin, monomeric α-amylase inhibitor, the CM3 subunit of tetrameric α-amylase inhibitor, and sucrose synthase from wheat; (3) anonymous cDNA probes from wheat that have been mapped by Sharp et al. (1989); (4) isozyme markers corresponding to aconitase, shikimate dehydrogenase, adenylate kinase, and endopeptidase. Meiotic metaphases of appropriate hybrids involving selected H-93 lines have been investigated by the Giemsa C-banding technique. The substitution of whole chromosomes [(5A) 5Mv; (4D) 4Mv; (5D) 5Mv; (7D) 7Mv] and chromosomal segments (1Mv; 3Mv; 5Mv; 7Mv) from the Mv genome of Aegilops ventricosa has been demonstrated. The distribution of selected markers among putative wheat-Ae. ventricosa addition lines has also been investigated. The 7Mv addition has been characterized for the first time, while the identity of the previously reported 5Mv and 6Mv additions has been confirmed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 86 (1993), S. 301-307 
    ISSN: 1432-2242
    Keywords: RFLP ; Polyploid ; Nondisjunction ; Interspecific hybrid ; Cottonwood
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary While constructing a genetic linkage map of a hybrid poplar genome (Populus trichocarpa x P. deltoides), we identified several restriction fragment length polymorphismus (RFLPs) for which the parental trees are heterozygous. Although 8 of the 11 F1 hybrid offspring inherited, as expected, single RFLP alleles from each parent, 3 F1 trees in the mapping pedigree inherited both maternal alleles along with a single paternal allele at some loci. Aneuploidy or polyploidy in these 3 F1 trees due to partial or complete nondisj unction during female gametogenesis is the simplest explanation for this finding. Of the 3 f1 offspring with supernumerary RFLP alleles 2 have triploid nuclear DNA contents as measured by fluorescence flow cytometry; the 3rd F1 with supernumerary alleles has a sub-triploid nuclear DNA content and is probably aneuploid. Among the tri/aneuploid hybrids, leaf quantitative traits either are skewed toward those values characteristic of the P. trichocarpa female parent (adaxial stomate density, petiole length: blade length ratio; abaxial color) or show transgressive variation (epidermal cell size). Abaxial leaf color was used to screen a large population of P. trichocarpa x P. deltoides hybrids for further evidence of tri/aneuploidy. In each case where a “white” abaxial leaf surface was observed and the nuclear DNA content measured, the hybrid proved to be tri/aneuploid. All sexually mature female triploids examined were sterile, although the inflorescences completed their development in the absence of embryo formation. The (probably) aneuploid F1 hybrid is a fertile female. Of 15 female P. trichocarpa parents used in crosses to P. deltoides, 10 produced one or more tri/aneuploid hybrid offspring. In an intraspecific cross using a P. trichocarpa female that had produced triploid hybrids with five different P. deltoides males, no tri/aneuploid offpsring were found.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 86 (1993), S. 329-332 
    ISSN: 1432-2242
    Keywords: RFLP ; Alfalfa ; Genetic map ; Segregation distortion ; Plant breeding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have developed a restriction fragment length polymorphism (RFLP) linkage map in diploid alfalfa (Medicago sativa L.) to be used as a tool in alfalfa improvement programs. An F2 mapping population of 86 individuals was produced from a cross between a plant of the W2xiso population (M. sativa ssp. sativa) and a plant from USDA PI440501 (M. sativa ssp. coerulea). The current map contains 108 cDNA markers covering 467.5 centimorgans. The short length of the map is probably due to low recombination in this cross. Marker order may be maintained in other populations even though the distance between clones may change. About 50% of the mapped loci showed segregation distortion, mostly toward excess heterozygotes. This is circumstantial evidence supporting the maximum heterozygote theory which states that relative vigor is dependent on maximizing the number of loci with multiple alleles. The application of the map to tetraploid populations is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 86 (1993), S. 811-821 
    ISSN: 1432-2242
    Keywords: Brassica ; Interspecific hybridization ; Amphidiploid ; RFLP ; Evolution ; Nuclear ; cytoplasmic interaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In a previous study we proposed that cytoplasmic genomes have played an important role in the evolution of Brassica amphidiploid species. Based on this and other studies, we hypothesized that interactions between the maternal cytoplasmic genomes and the paternal nuclear genome may cause alterations in genome structure and/or gene expression of a newly synthesized amphidiploid, which may play an important role in the evolution of natural amphidiploid species. To test this hypothesis, a series of synthetic amphidiploids, including all three analogs of the natural amphidiploids B. napus, B. juncea, and B. Carinata and their reciprocal forms, were developed. These synthetic amphidiploids were characterized for morphological traits, chromosome number, and RFLPs revealed by chloroplast, mitochondrial, and nuclear DNA clones. The maternal transmission of chloroplast and mitochondrial genomes was observed in all of the F1 hybrids examined except one hybrid plant derived from the B. rapa x B. oleracea combination, which showed a biparental transmission of organelles. However, the paternal chloroplast and mitochondrial genomes were not observed in the F2 progeny. Nuclear genomes of synthetic amphidiploids had combined RFLP patterns of their parental species for all of the nuclear DNA clones examined. A variation in fertility was observed among self-pollinated progenies of single amphidiploids that had completely homozygous genome constitutions. Comparisons between natural and synthetic amphidiploids based on restriction fragment length polymorphism (RFLP) patterns indicated that natural amphidiploids are considerably more distant from the progenitor diploid species than the synthetic amphidiploids. The utility of these synthetic amphidiploids for investigating the evolution of amphidiploidy is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 86 (1993), S. 833-836 
    ISSN: 1432-2242
    Keywords: T. aestivum ; RFLP ; Fingerprint
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Two probes, specific for HMW-glutenins and γ-gliadins have been used to identify 50 common wheat Italian cultivars, most of which are closely related, and four common wheat cultivars originating outside Italy. The probes revealed complex polymorphic patterns; three probe/enzyme combinations had the necessary sensitivity for the identification of all 54 cultivars. As already shown for potato and barley, the use of four-cutter restriction enzymes and polyacrylamide gels proved particularly useful for detecting polymorphism.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 86 (1993), S. 383-388 
    ISSN: 1432-2242
    Keywords: Mitochondria ; Inheritance ; RFLP ; Larix ; Conifers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Restriction fragment length polymorphisms between Larix leptolepis and Larix decidua were identified in heterologous hybridization experiments, using wheat mitochondrial DNA probes specific for atp9, coxI, nad3/rps12, and orf25. Analysis of eight individuals of each reciprocal hybrid of these two species revealed that mitochondrial DNA was maternally inherited. Furthermore, sequences homologous to wheat orf25 were also identified in Larix gmelini, Larix siberica, Larix olgensis, and Larix laricina, as well as Ginkgo biloba, Picea mariana, Picea glauca and Pinus contorta.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    ISSN: 1432-2242
    Keywords: DNA ; RFLP ; Soybean ; Genetic map
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Genetic markers were mapped in segregating progeny from a cross between two soybean (Glycine max (L.) Merr.) cultivars: ‘Minsoy’ (PI 27.890) and ‘Noir 1’ (PI 290.136). A genetic linkage map was constructed (LOD ⩾ 3), consisting of 132 RFLP, isozyme, morphological, and biochemical markers. The map defined 1550cM of the soybean genome comprising 31 linkage groups. An additional 24 polymorphic markers remained unlinked. A family of RFLP markers, identified by a single probe (hybridizing to an interspersed repeated DNA sequence), extended the map, linking other markers and defining regions for which other markers were not available.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 86 (1993), S. 573-578 
    ISSN: 1432-2242
    Keywords: COXI ; COXII ; Maternal inerhitance ; mtDNA ; RFLP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We have studied two mitochondrial DNA polymorphisms in 741 individuals from 16 allopatric populations ofPinus banksiana Lamb. andPinus contorta Dougl. Restriction fragments of both polymorphisms distinguished the two species qualitatively, except in aP. Banksiana population whose ancestors were involved in hybridization withP. contorta.COXI-associated restriction fragments were monomorphic within species, whileCOXII-associated restriction fragments were highly variable inP. contorta (Hes=0.68). Population differentiation was substantial inP. contorta (Fst=0.31 among subspecies; mean Fst=0.66 within subspecies) and consistent with predictions for maternally inherited markers. Plant mitochondrial markers appear to be useful for the investigation of seed migration routes, hybridization and introgression, breeding zone designation, and the development of germ plasm conservation sampling strategies.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    ISSN: 1432-2242
    Keywords: Hordeum vulgare ; Microdissection ; Microcloning ; Chromosome specific library ; RFLP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We have applied a refined microdissection procedure to create a plasmid library of the barley (Hordeum vulgare L.) chromosome arm 1HS. The technical improvements involved include synchronization of meristematic root tissue, a metaphase drop-spread technique, paraffin protection of the collection drop to avoid evaporation, and a motorized and programmable microscope stage. Thirteen readily-discernible telocentric chromosomes have been excised from metaphases of synchronized root-tip mitoses. After lysis in a collection drop (2 nl), the DNA was purified, restricted withRsaI, ligated into a vector containing universal sequencing primers, and amplified by the polymerase chain reaction. Finally, the amplified DNA was cloned into a standard plasmid vector. The size of the library was estimated to be approximately 44,000 recombinant plasmids, of which approximately 13% can be utilized for RFLP analysis. Tandem repetitive probes could be rapidly excluded from further analysis after colony hybridization with labelled total barley DNA. Analysis of 552 recombinant plasmids established that: (1) the insert sizes ranged between 70 and 1150 bp with a mean of 250 bp, (2) approximately 60% of the clones contained highly repetitive sequences, and (3) all single- or low-copy probes tested originate from chromosome 1HS. Four probes were genetically mapped, using an interspecificH. vulgare xH. spontaneum F2 population. One of these probes was found to be closely linked to theMla locus conferring mildew resistance.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    ISSN: 1432-2242
    Keywords: Triticum aestivum ; T. durum ; Aegilops longissimum ; Dasypyrum villosum ; Endonuclease ; Cytoplasm donor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract To elucidate the phylogenetic relationships and cytoplasmic types, restriction endonuclease fragment patterns of chloroplast (cp) and mitochondrial (mt) DNAs isolated from two different accessions of Dasypyrum villosum (L.) candargy were compared with those of tetraploid wheat (Triticum durum Desf., PI265007), hexaploid wheat (Triticum aestivum L., cv Chinese Spring), Aegilops longissimum (S. and M., in Muschli) Bowden and Hordeum vulgare L. T. aestivum and T. durum had identical restriction patterns for their cp and mtDNAs in digestions with four different enzymes. Likewise, no differences were found between the restriction fragment patterns of two accessions of D. villosum. But, there were distinct differences in chloroplast and mitochondrial DNA restriction fragment patterns between D. villosum and tetraploid and hexaploid wheats. A. longissimum (G609) showed a similar pattern to those wheats for PstI digestion of cpDNA. Organellar DNA from Hordeum vulgare (cv Himalaya) showed a distinctly different restriction pattern from those of wheat and D. villosum. These results suggest that D. villosum is unlikely to be the donor of cytoplasm to wheats, and its cytoplasmic organelles were also different from those of A. longissimum.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 86 (1993), S. 837-842 
    ISSN: 1432-2242
    Keywords: Androgenesis ; RFLP ; Maize ; Agronomic evaluation ; Gametoclonal variation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The homogeneity of anther culture-derived lines of maize has been evaluated by means of field observations and molecular markers. The homogeneity of the doubled haploid (DH) lines was shown by the absence of segregation for morphological oligogenic traits. The intravariance for polygenic traits for 42 DH and two conventionally derived lines was similar, which confirmed the homozygosity of the DH lines. More than 100 RFLP markers were tested on 189 DH lines derived from two crosses, DH5 x DH7 and A188 x DH7, and 60 single-seed descent (SSD, F6) lines derived from A188 x DH7. The overall rate of heterozygosity for all of the DH lines was approximatively 1% and pertained to 6 lines out of 189, while it was 8.5% for the SSD lines after four selfings. A precise description of the material used suggested that the events which led to this unexpected heterozygozity in DH lines were more likely to have occurred after rather than during the androgenetic process. Nine duplicated pairs of genotypes were found within the DH lines, indicating that a single microspore-derived structure can fragment to give two identical plantlets. Despite the extensive screening with more than 100 markers, only 2 lines showed unexpected banding profiles, and these were probably gametoclonal variants. The use of a direct regeneration system that avoids any callus phase might explain this low frequency of gametoclonal variation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    ISSN: 1432-2242
    Keywords: DNA ; RFLP ; QTL ; Soybean ; Recombinant inbreds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract An experimental test is described for linkages between RFLP markers and quantitative trait loci (QTL). Two hundred and eighty-four F7-derived recombinant inbred lines (RIL) obtained from crossing the soybean cultivars (Glycine max L. Merr.) ‘Minsoy’ and ‘Noir 1’ were evaluated for maturity, plant height, lodging, and seed yield. RIL exhibiting an extreme phenotype for each trait (earliest and latest plants for maturity, etc.) were selected, and two bulked DNA samples were prepared for each trait. A Southern transfer of the digested bulked DNA was hybridized with restriction fragement length polymorphism (RFLP) probes, and linkages with QTL were established by quantitating the amount of radioactive probe that bound to fragments defining alternative parental RFLP alleles. When an RFLP marker was linked to a QTL, one parental allele predominated in the bulked DNA from a particular phenotype; the other allele was associated with the opposite phenotype. When linkage was absent, radioactivity was associated equally with both alleles for a given phenotype (or with both phenotypes for a given allele). These results confirmed RFLP-QTL associations previously discovered by interval mapping on a smaller segregating population from the same cross. New linkages to QTL were also verified.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 87 (1993), S. 278-287 
    ISSN: 1432-2242
    Keywords: Maize ; RFLP ; Recombination ; Disturbed segregation ; DH/SSD lines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Doubled-haploid (DH) and single-seed-descent (SSD) lines in maize have been compared for quantitatively inherited traits and for RFLP markers. The comparisons of the distributions for agromorphological traits do not allow definite conclusions to be drawn on the similarity of the two reproductive systems. We have used more than 100 RFLP markers to provide a precise description of the parental allele frequency and the recombination fractions. A comparison of two DH populations shows that non-random meiotic reassortment is influenced by differences in the anther culture capacities of the two parental lines. For the DH lines derived from the cross DH5 x DH7, involving two responsive lines in anther culture, the distortion in segregation (P 〈 0.05) affected less than 20% of the genome with half of the deviations towards each parent. DH lines derived from the cross A188 x DH7, where A188 is a non-responsive line, showed more than twice this level of distortion and an excess of DH7 alleles was found for almost all of the skewed loci. The recombination fractions were homogeneous between the two DH populations for most of the genome. The genome sizes calculated with the DH and the SSD lines derived from the same cross, A188 x DH7, were also similar, which suggests that no selection against recombinant gametes occurs during anther culture. The observed recombination fraction after five meioses (SSD) is on average twice as large as after one meiosis (DH). No difference is observed for recombination fractions greater than 20%. Despite a precise description of the material at the molecular level, it has not been possible to make a definite conclusion as to whether or not the differences in some morphological characters are the consequences of differences in the segregation ratio and/or the recombination frequency. However, the agromorphological evaluation shows a narrow range in differences between the two types of lines and suggests that the use of DH lines is possible in breeding programmes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 88 (1994), S. 273-278 
    ISSN: 1432-2242
    Keywords: RFLP ; Genetic linkage mapping ; Pinus taeda L.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A genetic linkage map for loblolly pine (Pinus taeda L.) was constructed using segregation data from a three-generation outbred pedigree consisting of four grandparents, two parents, and 95 F2 progeny. The map was based predominantly on restriction fragment length polymorphism (RFLP) loci detected by cDNA probes. Sixty-five cDNA and three genomic DNA probes revealed 90 RFLP loci. Six polymorphic isozyme loci were also scored. One-fourth (24%) of the cDNA probes detected more than 1 segregating locus, an indication that multigene families are common in pines. As many as six alleles were observed at a single segregating locus among grandparents and it was not unusual for the progeny to segregate for three or four alleles per locus. Multipoint linkage analysis placed 73 RFLP and 2 isozyme loci into 20 linkage groups; the remaining 17 RFLP and 4 isozyme loci were unlinked. The mapped RFLP probes provide a new set of codominant markers for genetic analyses in loblolly pine.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 88 (1994), S. 97-101 
    ISSN: 1432-2242
    Keywords: Triticum aestivum ; T. speltoides ; Meiotic chromosome pairing ; Alien transfer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Diploid-like chromosome pairing in polyploid wheat is controlled by several Ph (pairing homoeologous) genes with major and minor effects. Homoeologous pairing occurs in either the absence of these genes or their inhibition by genes from other species (Ph I genes). We transferred Ph I genes from Triticum speltoides (syn Aegilops speltoides) to T. aestivum, and on the basis of further analysis it appears that two duplicate and independent Ph I genes were transferred. Since Ph I genes are epistatic to the Ph genes of wheat, homoeologous pairing between the wheat and alien chromosomes occurs in the F1 hybrids. Using the Ph I gene stock, we could demonstrate homoeologous pairing between the wheat and Haynaldia villosa chromosomes. Since homoeologous pairing occurs in F1 hybrids and no cytogenetic manipulation is needed, the Ph I gene stock may be a versatile tool for effecting rapid and efficient alien genetic transfers to wheat.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 88 (1994), S. 30-32 
    ISSN: 1432-2242
    Keywords: Triticum aestivum ; DNase ; Nuclease ; Cytogenetics ; Gene mapping
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract DNA-degrading enzymes of 24.0 kDa and 27.0 kDa were observed to have different activities in two common wheat (Triticum aestivum L.) cultivars, ‘Wichita’ and ‘Cheyenne’. A substrate-based SDS-PAGE assay revealed that these two enzymes were much more active in ‘Wichita’ than in ‘Cheyenne’. Genes controlling the activities of these two enzymes were localized on chromosome 2D by testing DNA-degrading activities in reciprocal chromosome substitution lines between ‘Wichita’ and ‘Cheyenne’. While the allele on ‘Wichita’ chromosome 2D stimulated the activities of the 24.0- and 27.0-kDa enzymes in Cheyenne, the allele on ‘Cheyenne’ chromosome 2D did not reduce the activities of the 24-kDa and 27-kDa enzymes in ‘Wichita’. Whether these genes code for the DNA-degrading enzymes themselves or for factors that regulate the enzyme activities remains unknown.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...