ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Chromosoma 18 (1966), S. 407-420 
    ISSN: 1432-0886
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The missing chromosomal elements were cytologically identified in a primary monosomic (haplo-11) and 18 tertiary monosomics (lacking interchanged chromosomes) induced by radiation in the tomato. For the tertiary monosomics all interchanges occurred in the centromeres, and, as with single arms deficiencies in the same materials, deficiencies are tolerated for only 15 of the 24 arms of the complement. Non-homologous pairing was frequently observed in the univalent pachytene chromosomes. The monosomic condition was not transmitted to any of the 11,981 progeny of ten tested monosomics. Reproductive fertility and gross morphology were also studied.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Chromosoma 23 (1968), S. 452-484 
    ISSN: 1432-0886
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Cytological studies of 74 deficiencies of tomato chromosomes induced by radiation and identified by the pseudo-dominant technique reveal the loci of 35 genes on 18 of the 24 arms of the complement. These findings integrated with data obtained from various trisomic types establish centromere positions, orientation of linkage groups, and markers on all but three of the arms. The prospects of obtaining a specific kind of deficiency for a given region were found to depend on : (1) kind of radiation applied, (2) (non-random) breakage frequency in different parts of the chromosome, (3) stability of broken ends, (4) tolerance of deficiency in different parts of the genome, and (5) relative vigor of the mutant homozygote used to detect the deficiency. Aspects of the frequently observed non-homologous pairing phenomenon are presented and discussed. Marker genes whose loci are known appear to be non-randomly distributed between and within chromosomes. Chromosome exchanges as determined by genetic crossing over and cytologically observed chiasmata are likewise non-randomly distributed between and within chromosomes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-2242
    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 ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 45 (1974), S. 43-46 
    ISSN: 1432-2242
    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 ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Genetica 33 (1963), S. 167-183 
    ISSN: 1573-6857
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Meiotic chromosome cytology was compared betweenSolanum pennellii, Lycopersicon esculentum, and the F1 hybrid. Pachytene chromosomes are very similar in gross morphology, but several of theS. pennellii chromosomes were found to have somewhat longer chromatic regions with discrete chromomeres, and darkly staining chromomeres in the achromatic regions. Little evidence could be found for the existence of rearrangements between chromosomes of the two species. With respect to chromomere pattern, on the other hand, a number of differences were seen. Meiosis in the hybrid is strictly regular. Only size inequalities occur in certain bivalents. Considering the evidence from chromosome pairing, hybridization compatibility, hybrid fertility, and plant morphology, it is concluded that the phylogenetic relationship is much closer betweenS. pennellii andL. esculentum than it is between either one andS. lycopersicoides. Attention is called to the present unsatisfactory placement ofS. pennellii and to the need for revising the taxonomy to place it andL. esculentum in the same genus, possibly in the same subgeneric category.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1573-6857
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Various genetic and cytogenetic techniques were applied to an analysis of the linkage map of chromosome 4-a chromosome that is considered to be representative of the tomato complement. Loci have been approximated by standard F2 linkage tests for 18 genes, including six on the short arm and 12 on the long arm, covering a map distance of 132 units (c.m.). The loci of four key markers were approximated on pachytene chromosomes by a study of radiation-induced deficiencies:clau near the end of the short arm,ful near the euchromatic-heterochromatic boundary of the short arm,ra near the same region on the long arm, ande in the middle of the long arm. Normal transmission for a presumedra deficiency suggests that this gene lies in the heterochromatin of 4L. According to tertiary trisomic segregation,w-4, known by linkage test to be proximal tora, resides on 4L, therefore probably also in the heterochromatic region. The centromere is consequently delimited to a region of 4 c.m. betweenful andw-4. The resultant maps reveal a very much lower crossover rate within heterochromatin—estimated at 0.8 c.m./μ—than for euchromatin—estimated at 4.8 c.m./μ for the short arm and 5.7 for the long arm. Also apparent is a strong tendency of the genes to concentrate toward the centromere of the genetic map and in the proximal sections of the euchromatin of the cytological map. Studies were made of the genetic transmission of various small deficiencies on chromosome 4 as well as a newly discovered deficiency fornv on chromosome 9, supporting the following conclusions. Regardless of their size, deficiendies of euchromatin are not transmitted. Deficiencies of heterochromatin are transmitted to a varying extent depending on their size. A presumed deficiency forra that is too small to be detected cytologically was transmitted without adverse effect on gametes. Somewhat larger deficiencies may be transmitted at reduced rates by female gametes and the largest at extremely low rates, even on the female side.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1573-5060
    Keywords: Lycopersicon esculentum ; tomato ; Epitrix hirtipennis ; tobacco flea beetle ; insect resistance ; preference reaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary In comparisons made under typical summer conditions in the field at Davis, California, the foliage of the anthocyanin-deficient mutant af proved to be much more susceptible to attack by Epitrix hirtipennis (Melsheimer) than that of the isogenic normal line, normal cultivars, or any other tested mutant. Since a relatively uniform level of damage was observed in leaves of various ages that contacted the soil, the interaction is probably of a preference rather than antibiotic nature. A comparison with nine other anthocyaninless mutants proved that anthocyanin deficiency is not responsible for susceptibility. The severe reduction of glandular hairs and consequent lack of foliage aroma—hitherto unsuspected pleiotropic effects of af—probably account for the high susceptibility of this mutant. The evolutionary significance of the distinct foliage aromas characteristic of each tomato species is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1573-5060
    Keywords: breeding ; Botrytis cinerea ; gray mold ; introgression ; isozymes ; tomato
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Solanum lycopersicoides Dun. is a wild nightshade native to Chile and Peru that possesses many traits of potential interest to tomato breeders, including environmental stress tolerance, resistances to disease and insect pests, and certain fruit quality characteristics. Sexual and somatic hybrids with the cultivated tomato (Lycopersicon esculentum Mill.) are readily obtained, yet have a strong tendency towards male-sterility combined with unilateral incompatibility, barriers that have deterred breeding efforts in the past. We report herein the synthesis of a partially male-fertile F1 hybrid by sexual crosses between tomato and a recently collected population of S. lycopersicoides. Over 280 BC1 plants were obtained by directed backcrossing to tomato at the diploid level, of which 58 were sufficiently fertile to permit selfing or additional backcrosses. The transmission of S. lycopersicoides genetic markers into a uniform L. esculentum background was confirmed with 24 isozyme or morphological loci on 11 of the 12 alien chromosomes. Potentially useful tolerance to gray mold (Botrytis cinerea) was demonstrated by inoculation of stem cuttings with mycelial plugs: at 6 days post-inoculation, the intergeneric hybrid showed little evidence of disease progression and the length of stem lesions averaged only one third that of susceptible controls.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Plant systematics and evolution 139 (1981), S. 11-45 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Solanaceae ; Lycopersicon ; Solanum pennellii ; Allozymes ; electrophoresis ; isozymes ; mating systems ; self-incompatibility
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Genetic variation—primarily in 19 genetic loci of seven enzyme systems—was analyzed in accessions from various parts of the geographic range ofSolanum pennellii, which according to all tested biosystematic criteria behaves like a species ofLycopersicon. In comparison with the largely sympatricL. hirsutum andL. pimpinellifolium, this species exhibits the same trends of reduced allogamy and decreased genetic variation toward the north and south margins of its distribution, though to a much lesser degree; it does not exhibit their trends toward smaller flower size in the same peripheral regions. All three species agree to a considerable extent in the ranking of their tested loci in respect to degree of variablility; however, overall polymorphy is highest inS. pennellii. Except for the appearance of self-compatibility at its southernmost margin,S. pennellii is exclusively and rigidly self-incompatible. Alleles are distributed much more uniformly over the range than in the previously mentioned species, marginal and internal endemic mutants being much less abundant. A marked geographic disagreement is evident in regions of high and low variation. These differences in patterns of genetic variability are reconciled in terms of observed differences in mating systems, probable age of distributions, and adaptive strategies.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1615-6110
    Keywords: Lycopersicon hirsutum ; Solanaceae ; Allozymes ; clinal variation ; electrophoresis ; evolution of mating systems ; isozymes ; self-incompatibility
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Populations in the central part of the distribution are mostly self-incompatible and tend to be highly variable for allozymic and morphological characters; those in the north and south limits are entirely self-compatible and tend to be genetically highly uniform. Gradations in variability are observed in the intermediate regions. Flower size tends to diminish in the peripheral areas. The extensive differences in genotype observed between the north and south marginal populations are not compatible with the concept of a single origin of self-compatibility, but suggest, along with other evidence, that the substitution of different alleles resulted from differentiation in the marginal areas from older, self-incompatible stocks of the central region. The conclusions regarding patterns of genetic variation and nature of evolution of mating systems inL. hirsutum conform to a remarkable extent with those reached previously forL. pimpinellifolium, a species that is distinct in morphology and ecological preferences yet has a similar latitudinal distribution.
    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...