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  • Triticum aestivum  (34)
  • Drosophila  (23)
  • Springer  (57)
  • Annual Reviews
  • Blackwell Publishing Ltd
  • 2005-2009
  • 1990-1994
  • 1980-1984  (57)
  • 1983  (57)
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  • 2005-2009
  • 1990-1994
  • 1980-1984  (57)
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  • 1
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    Springer
    Development genes and evolution 192 (1983), S. 164-170 
    ISSN: 1432-041X
    Keywords: Drosophila ; Imaginal disc ; Morphogenesis ; Tissue culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The early morphogenesis of the eye-antennal disc ofDrosophila in response to 20-hydroxy ecdysone involves the curling of the eye anlagen dorsally over the antenna. During this process, the area of the peripodial membrane is substantially reduced. The peripodial membrane is taut at this stage, and if it is cut the curling of the disc cannot continue, and the eye anlagen returns to its original position within one minute of the operation. In contrast, cutting the columnar epithelium between the eye and antennal anlagen does not disrupt curling, but actually facilitates it. During curling, the cells of the peripodial membrane appear healthy, and exhibit basal extensions. We suggest that the curling of the eye is mediated by the conversion of cuboidal peripodial membrane cells into pseudostratified columnar epithelium at the edges of the peripodial membrane. Subsequently, cells of the peripodial membrane secrete first a pupal cuticle, and then an imaginal cuticle.
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  • 2
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    Development genes and evolution 192 (1983), S. 275-279 
    ISSN: 1432-041X
    Keywords: Evagination ; Morphogenesis ; Metamorphosis ; Female genital disc ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The morphology of the evaginating female genital disc ofDrosophila melanogaster was examined at different stages of metamorphosis. The observations show that the internal genital organs are derived from the anterior half of the disc and that their morphogenesis is mainly a protrusion of the different primordial areas of the disc epithelium. The external genital and anal derivatives originate from the posterior half of the disc, which undergoes complex rearrangements during metamorphosis. The disc opens along the posterior margin and the dorsal and ventral epithelia evert and thereby completely reverse their anteroposterior orientation. Dramatic elongation has been observed during the formation of the seminal receptacle. The cells of the repressed male genital primordium do not form any recognizable structures and are assumed to be eliminated during metamorphosis.
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  • 3
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    Development genes and evolution 192 (1983), S. 299-302 
    ISSN: 1432-041X
    Keywords: Differentiation ; Teratogens ; Drosophila ; 5-Azacytidine ; Methylation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The effects of cytidine and cytidine analogs were studied inDrosophila embryonic cell cultures and two wild-type established cell lines, Oregon-R and Schneider line 2. Primary embryonic cultures have been shown to be an excellent system for the study of embryonic development; a number of cell types undergo normal differentiation in vitro. Treatment of these cultures with putative teratogens resulted in an inhibition of muscle and/or neuron differentiation in our study. Treatment of these cells with cytidine and seven other analogs had no effect on neuron and muscle differentiation. The compound 5-azacytidine, when added to primary cell cultures, inhibited normal differentiation at subtoxic doses while inducing the production of three proteins that comigrate with the heat-shock proteins, hsp 23, 22a and 22b. 5-Azacytidine did not stimulate differentiation in Oregon-R or SchneiderDrosophila cell lines. The in vitro blockage of differentiation by 5-azacytidine suggests that it may act as a teratogen.
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  • 4
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    Development genes and evolution 192 (1983), S. 280-284 
    ISSN: 1432-041X
    Keywords: Evagination ; Morphogenesis ; Metamorphosis ; Intersexual genital disc ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Morphogenetic movements of the intersexual genital disc of thedoublesex-dominant mutant ofDrosophila melanogaster were followed during metamorphosis. Intersexual genital discs contain well developed genital primordia of both sexes as well as an anal primordium, and all of these primordia evaginate simultaneously. The female genital primordium is deflected to the ventral side by the male genital primordium which is located anterior to it. Subsequently the anterior parts of the two genital primordia project their internal appendages in parallel in the anterior direction. The morphogenetic movements closely resemble those of the corresponding parts of normal males and females. The disc opens at the stalk along the posterior edge and the two genital primordia completely evert their posterior parts. These areas undergo complex rearrangements whereby the anlage for the male genital arch as well as that for the 8th tergite evert and move around the lateral side of the disc. They both fuse dorsally after enclosing the anal tube. The formation of the characteristic abnormalities of the intersexual genitalia seems not to result simply from spatial problems of the simultaneous evagination of the genital anlagen but rather to be a direct result of the ambiguous genetic signalling in the intersexual cells of these primordia.
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  • 5
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    Development genes and evolution 192 (1983), S. 337-346 
    ISSN: 1432-041X
    Keywords: Drosophila ; Gynandromorphs ; Genital disc ; Compartments ; Evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The genital imaginal disc ofDrosophila differentiates the terminalia, i.e. the genitalia and analia, of both sexes. It represents a composite anlage, containing a female genital primordium, a male genital primordium and an anal primordium. In normal males and females, only one of the two genital primordia differentiates; the other is developmentally repressed. Therefore, cell-lineage relationships between the male and female genital primordia can only be studied in sexual mosaics which differentiate female and male cells. We producedMinute (M)‖non-Minute(M+) gynandromorphs and selected those with sexually mosaic terminalia for a cell-lineage analysis. In these mosaics, either the male (XO) or female (XX) cells wereM + and thus had a growth advantage. The differential growth rates served as a tool to detect clonal restrictions. In control gynandromorphs (M +‖M +), the amount of female genitalia differentiated was largely independent of the amount of male genitalia present. In contrast, male and female anal structures, as a rule, added up to one full set. The same was true for the experimentalM‖M + gynandromorphs, but the contribution ofXX andXO cells to mosaic terminalia changed drastically due toM + cells competing successfully against the more slowly growingM cells. Specific subsamples ofM‖M + gynandromorphs showed thatM cells in a non-mosaic primordium are shielded from cell competition taking place in the neighbouring mosaic primordium. We conclude that the three primordia of the genital disc represent developmental compartments. In the genital primordia, even developmentally repressedM + cells compete successfully against developmentally activeM cells.
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  • 6
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    Development genes and evolution 192 (1983), S. 48-50 
    ISSN: 1432-041X
    Keywords: Drosophila ; Hybrid lethality ; Imaginal discs ; Interspecific transplantation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Females ofDrosophila melanogaster, crossed with males ofDrosophila mauritiana, produce only female offspring. The male hybrid larvae grow very slowly, fail to pupate and die after prolonged larval life. Imaginal discs from these male hybrids transplanted into Drosophila melanogaster larvae can give rise to adult structures with normal patterns. Differentiation of hybrid imaginal disc tissue is improved by short term culture in non-hybrid larvae prior to metamorphosis, suggesting that the hybrid larval haemolymph is inadequate to sustain normal imaginal disc growth. This may represent the physiological basis of the reproductive isolating mechanism separating the twoDrosophila species
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  • 7
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    Development genes and evolution 192 (1983), S. 270-274 
    ISSN: 1432-041X
    Keywords: Fate map ; Repressed primordium ; Sex determination ; Genital disc ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The female genital disc ofDrosophila melanogaster was cut into distinct fragments, and the prospective fates of the fragments were determined by putting them through metamorphosis in host larvae. The dorsal epithelium contains the anlagen for the anal plates and parovaria, as well as the repressed male genital primordium. The ventral epithelium gives rise to all of the female genital structures except for the parovaria. The results were compared with published fate maps and observations made in experiments with sex-transforming mutations. This allowed us to establish a detailed three-dimensional fate map of the female genital disc, which shows a well-developed female genital primordium in the ventral epithelium, a repressed male genital primordium in the anterior part of the dorsal epithelium and an anal primordium in the posterior region of the dorsal disc epithelium.
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  • 8
    ISSN: 1432-041X
    Keywords: Drosophila ; Cell degeneration ; Imaginal disc ; Basal lamina ; Blood cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The mutationsvestigial (vg; recessive) andUltravestigial (vg U; dominant) ofDrosophila melanogaster give rise to identical mutant adult phenotypes in which much of the cases this results from cell death in the presumptive wing margin of the wing disc in the third larval instar, but the process of cell degeneration is quite different in the two mutants. Invg cell death occurs continuously throughout the third larval instar, while invg U it occurs only in the early third instar. Cells fragment and some of the fragments condense, becoming electron dense (“apoptosis”). Both condensed and ultrastructurally normal cell fragments are extruded to the basal side of thevg disc epithelium. They accumulate under the basal lamina in the wing pouch area until they are phagocytosed by blood cells entering the wing pouch during the six hours following pupariation. Fragments are not extruded from thevg U epithelium but are apparently phagocytosed by neighboring epithelial cells. The basal lamina undergoes mophological changes following pupariation and is phagocytosed by blood cells in both wild-type andvestigial, but investigial the degenerated cell fragments are also engulfed by the same blood cells.
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  • 9
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    Development genes and evolution 192 (1983), S. 317-326 
    ISSN: 1432-041X
    Keywords: Neurogenic mutations ; Topological specificity ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Neurogenic mutations have been found to cause the neuralization of certain regions of the ectoderm and yet to permit normal development of the remaining embryonic cells. Thus, it seems that the activity of the wild-type alleles of these genes is dispensable in a considerable fraction of the embryo during wild-type development. This effect might be a consequence of the cells' position within the embryo; alternatively, it might be independent of the position but be due rather to the genetic activity experienced by the cells previous to their commitment. The results described in this paper indicate that genes controlling patterning along the embryonic dorso-ventral perimeter (dorsal and Toll) are epistatic to genes controlling neurogenesis, their activity deciding which ectodermal cells are susceptible to neurogenesis. Using alleles with low expressivity, evidence was obtained showing that the tracheal placodes define the boundary of the territory which has neurogenic abilities at thoracic and abdominal levels.
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  • 10
    ISSN: 1432-041X
    Keywords: Early neurogenesis ; Neurogenic mutants ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The central nervous system (CNS) ofDrosophila develops from precursor cells called neuroblasts. Neuroblasts segregate in early embryogenesis from an apparantly undifferentiated ectoderm and move into the embryo, whereas most of the remaining ectodermal cells continue development as epidermal cell precursors. Segregation of neuroblasts occurs within a region called the neurogenic field. We are interested in understanding how the genome ofDrosophila controls the parcelling of the ectoderm into epidermal and neural territories. We describe here mutations belonging to seven complementation groups which effect an abnormal neurogenesis. The phenotypes produced by these mutations are similar. Essential features of these phenotypes are a conspicuous hypertrophy of the CNS accompanied by epidermal defects; the remaining organs and tissues of the mutants are apparently unaffected. The study of mutant phenotype development strongly suggests this phenotype to be due to misrouting into the neural pathway of development of ectodermal cells which in the wildtype would have given rise to epidermal cells, i.e. to an initial enlargement of the neurogenic region at the expense of the epidermogenic region. These observations indicate that the seven genetic loci revealed by the mutations described in this study contribute to control the neurogenic field. The present results suggest that in wildtype development neurogenic genes are supressed within all derivatives of the mesoderm and endoderm and some derivatives of the ectoderm, and conditionally expressed in the remaining ectoderm. The organisation of the neurogenic field in the wildtype is discussed.
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  • 11
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    Biochemical genetics 21 (1983), S. 199-211 
    ISSN: 1573-4927
    Keywords: Drosophila ; lactate dehydrogenase ; isozymic pattern ; development ; isozymic conversion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Partially purified lactate dehydrogenase (LDH) from third-instar larvae displays two bands (one major and one minor) on polyacrylamide gels. Analogous preparations from pupae and adults exhibit three LDH-staining bands (one major and two minor) in a similar pattern. The migration of the major band is similar for larvae, pupae, and adults, while the two minor LDH bands of pupae and adults migrate more slowly than the minor larval band. It has been shown that larval LDH incubated with β-nicotinamide adenine dinucleotide exhibits two additional minor bands with an electrophoretic mobility similar to that of the minor bands of both pupae and adults. The intensity of the minor larval LDH band (exhibited also by untreated preparations) is drastically reduced. This fact indicates that the life-cycle stage-dependent LDH isozymic distribution is possibly due to a posttranslational effect(s). Highly purified LDH from larvae, pupae, or adults, obtained by an affinity chromatography procedure, displays just one dispersed band, located in the area between the band 5 and the band 6 exhibited by crude extract preparations. These data, in combination with the lack of difference in catalytic properties among enzymes from larvae, pupae, and adults, suggest that LDH synthesis is controlled by the same single structural gene at all developmental stages.
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  • 12
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    Biochemical genetics 21 (1983), S. 199-211 
    ISSN: 1573-4927
    Keywords: Drosophila ; lactate dehydrogenase ; isozymic pattern ; development ; isozymic conversion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Partially purified lactate dehydrogenase (LDH) from third-instar larvae displays two bands (one major and one minor) on polyacrylamide gels. Analogous preparations from pupae and adults exhibit three LDH-staining bands (one major and two minor) in a similar pattern. The migration of the major band is similar for larvae, pupae, and adults, while the two minor LDH bands of pupae and adults migrate more slowly than the minor larval band. It has been shown that larval LDH incubated with β-nicotinamide adenine dinucleotide exhibits two additional minor bands with an electrophoretic mobility similar to that of the minor bands of both pupae and adults. The intensity of the minor larval LDH band (exhibited also by untreated preparations) is drastically reduced. This fact indicates that the life-cycle stage-dependent LDH isozymic distribution is possibly due to a posttranslational effect(s). Highly purified LDH from larvae, pupae, or adults, obtained by an affinity chromatography procedure, displays just one dispersed band, located in the area between the band 5 and the band 6 exhibited by crude extract preparations. These data, in combination with the lack of difference in catalytic properties among enzymes from larvae, pupae, and adults, suggest that LDH synthesis is controlled by the same single structural gene at all developmental stages.
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  • 13
    ISSN: 1573-4927
    Keywords: Drosophila ; alcohol dehydrogenase ; enzyme polymorphisms, activity ratios
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Representatives of five allozymic classes of Drosophila alcohol dehydrogenase have been compared with respect to their activity levels on two alcohol substrates, quantities of ADH protein, and stability in crude extracts. Within each allozymic class, strains from widely diverse geographic locations differ in their enzyme activity levels but are identical for a measure known as “activity ratio,” which is obtained by dividing the average activity reading on isopropanol by that obtained with ethanol. They are also similar in the rate at which ADH activity declines in crude extracts held at 25°C. For several of the fast-resistant and fast-moderate strains, differences in ADH activity are associated with differences in the amount of enzyme present. The catalytic efficiencies of the fast-resistant forms are considerably lower than those of the fast-moderate allozymes. The origin and persistence of the rare but ubiquitous fast-resistant allozyme is discussed.
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  • 14
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    Biochemical genetics 21 (1983), S. 703-711 
    ISSN: 1573-4927
    Keywords: Drosophila ; glucose-6-phosphate dehydrogenase ; polymorphism ; sequential electrophoresis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Studies were undertaken to investigate two critical aspects of the glucose-6-phosphate dehydrogenase polymorphism in Drosophila melanogaster. The first investigation unequivocally maps the genetic site of the G6PD locus to the X chromosome. The second study subjects a set of isochromosomal lines to sequential electrophoresis in an attempt to uncover common molecular heterogeneity within the global polymorphism, assuming that this variation may have gone undetected under conventional electrophoretic conditions. The genetic site was mapped following the segregation of the two common electrophoretic alleles, a so-called null allele, and two rare electrophoretic variants. From the pooled results, the Zw locus mapped to 62.9 on the X chromosome relative to the flanking markers car (at 62.5) and sw (at 64.7). A set of 126 iso-X chromosomal lines of diverse geographic origin was subjected to sequential electrophoresis under three different acrylamide conditions in addition to the conventional starch electrophoretic system. No additional variation beyond the common diallele polymorphism was seen.
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  • 15
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    Behavior genetics 13 (1983), S. 17-27 
    ISSN: 1573-3297
    Keywords: pupation site ; pupation height ; artificial selection ; Drosophila ; density-dependent behavior ; genotype-environment interaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Selection for increased pupation height was carried out for 17 generations in two lines ofDrosophila simulans derived from a genetically heterogeneous base population. The realized heritability for mean pupation height in each line, calculated over the 17 generations, did not differ significantly from zero. Both selected lines tended to pupate away from the center of the culture medium to a greater extent than the control in the latter generations of the experiment but not in earlier generations. Pupation height may have been refractory to artificial selection because of an adaptation of this species to pupate on the larval food source. In a subsequent experiment, each line was tested at three larval densities in an apparatus different from the one used for selection. Each successively higher density showed a corresponding increase in pupation height. Both selected lines had higher mean pupation heights than the control line. The differences between lines became more pronounced as the larval density increased.
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  • 16
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    Biochemical genetics 21 (1983), S. 365-374 
    ISSN: 1573-4927
    Keywords: alcohol dehydrogenase ; NAD+ levels ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Previous studies carried out in mammalian systems indicated that an organism's NAD+/NADH balance is carefully regulated but can be destabilized by dietary stresses. Since Drosophila alcohol dehydrogenase (ADH) uses NAD+ to remove a hydrogen from ethanol in the first step of alcohol catabolism, it is possible that under alcohol stress conditions the in vivo NAD+ levels in Drosophila may decrease. In this study genetically homozygous flies were stressed with maximally sublethal concentrations of ethanol (10%) for periods of up to 24 hr. The results indicate that NAD+ levels do in fact drop by at least 20% in response to ethanol stress. Evidence is presented that suggests that this decrease is the direct result of ADH-mediated catabolism.
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  • 17
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    Theoretical and applied genetics 66 (1983), S. 101-109 
    ISSN: 1432-2242
    Keywords: Anther culture ; Culture temperature ; Induction frequency ; Pollen callus (plantlet) ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The response of anther culture to culture temperature was studied in detail using many varieties, F1 hybrids and pollen-derived lines of wheat (Triticum aestivum) as materials. The suitable culture temperature for inducing pollen callus (or embryoids) in wheat anther culture ranged from 26 °C to 30 °C, varying with genotypes. But for the great majority of wheat genotypes the suitable culture temperatures lay between 28 °C and 30°C. The most significant genotypic variation in the response to culture temperature was observed in the comparison between the culture at 33 °C for eight days followed by culture at 25 °C (or 26 °C) and the continuous culture at 25 °C (or 26 °C). This genotypic variation in the response to culture temperature is a heritable character which may be controlled by multiple genes. The effect of culture at 30 °C for eight days followed by culture at 26 °C was similar to, or in some cases, better than that of continuous culture at 28 °C, and the effect of culture at 32 °C for eight days followed by culture at 28 °C was similar to that of continuous culture at 30 °C. In the range from 26 °C to 32 °C, the overwhelming majority of pollen calli emerged before the 40th day after anther inoculation, and the higher the culture temperature, the earlier and more concentrated the emerging period of the pollen callus. The pollen callus obtained at high temperatures above 28 °C should be transferred in time onto the regeneration medium at 25°–27°C to induce shoots.
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  • 18
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    Theoretical and applied genetics 64 (1983), S. 255-258 
    ISSN: 1432-2242
    Keywords: Triticum aestivum ; Wheat ; Malate dehydrogenase ; Chromosomal location
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The malate dehydrogenase (E.C. no 1.1.1. 37) of Triticum aestivum L. cv. Chinese Spring, shows two activity zones. The results obtained support the hypothesis that the malate dehydrogenase isozymes of zone II are dimers composed of the six possible combinations of subunits coded by triplicate genes located in the long arms of chromosomes of the homoeologous group 1.
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  • 19
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    Theoretical and applied genetics 66 (1983), S. 111-121 
    ISSN: 1432-2242
    Keywords: Triticum aestivum ; Agropyron ; Intergeneric hybrids ; Embryo culture ; Chromosome pairing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Intergeneric hybrids of Triticum aestivum (2n=42,AABBDD) with Agropyron ciliare (2n= 28,SSYY), A. trachycaulum (2n=28,SSHH), A. yezoense (2n=28,SSYY) and A. scirpeum (2n=28) are reported for the first time. F1 hybrids of T. aestivum were also produced with A. intermedium (2n=42,E1E1E2E2Z1Z1) and A. junceum (2n=14,JuJu). All wheat-Agropyron hybrids were obtained by embryo rescue technique. Cultivars and reciprocal crosses differed for seed set, seed development and F1 plant production. The F1 hybrids were sterile. Attempts to obtain amphiploids were unsuccessful. However, backcross derivatives were obtained with wheat as the recurrent parent. The level of chromosome pairing in A. trachycaulum x wheat, A. yezoense x wheat and wheat x A. junceum hybrids provided no evidence of homologous or homoeologous pairing. Mean pairing frequencies in A. ciliare x wheat, wheat x A. scirpeum and wheat x A. intermedium hybrids indicated homoeologous or autosyndetic pairing. Ph gene was more effective in regulating homoeologous pairing in A. yezoense x wheat hybrids than in A. ciliare x wheat hybrid. Chromosome pairing data of BC1 derivatives indicated that either some of the wheat chromosomes were eliminated or Agropyron chromosomes caused reduced pairing of wheat homologues.
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  • 20
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    Theoretical and applied genetics 65 (1983), S. 41-46 
    ISSN: 1432-2242
    Keywords: Triticum aestivum ; Wheat ; Protein ; Mutation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Poor adaptability or functional quality of much germplasm used for breeding high-protein hard red winter wheats prompted mutagenesis as an alternative means of increasing grain protein content. Four hard red winter wheat genotypes — KS644 (‘Triumph// Concho/Triumph’), ‘Kaw’, ‘Parker’, and ‘Shawnee’ — were treated with 0.40 M ethyl methanesulfonate (EMS). Advanced lines (M8-M10) were selected that had a 3-year mean grain protein advantage of 0.7% to 2.0% over controls. Increased grain protein content was generally associated with decreased grain yield and kernel weight, but some high-protein mutant lines had yields or kernel weights similar to those of original genotypes. Changes in height and lodging induced by EMS were generally favorable, most mutants being shorter and lodging less than controls, but blooming date was generally delayed, a deleterious change. One line also changed from resistant to segregating for wheat soil-borne mosaic virus. Mutant lines might be utilized in cross-breeding programs, particularly if negative pleiotropic effects and linkages are absent.
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  • 21
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    Theoretical and applied genetics 65 (1983), S. 173-180 
    ISSN: 1432-2242
    Keywords: Disruptive selection ; Linkage disequilibrium ; Genetic variance ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Theoretical predictions of changes in variance with disruptive selection have used models of infinitely many genes so the increase in variance was necessarily due to linkage disequilibrium. With small numbers of loci, the disequilibrium is shown still to comprise the major part of the changes in variance. In a replicated experiment with Drosophila melanogaster, disruptive selection was practised for three generations, and this was followed by 5 or 7 generations of random mating. The heritability, as estimated from regression of progeny on parent, rose from 37% to 68% on selection, and subsequently declined to 45% on random mating. Changes of variance can be interpreted invoking the build up of linkage disequilibrium during selection followed by its breakdown upon relaxation. The results agree well with those obtained from Monte Carlo simulation.
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  • 22
    ISSN: 1432-2242
    Keywords: Drosophila ; Enzyme polymorphisms ; Latitudinal clines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The octanol dehydrogenase (Odh) and acid phosphatase (Acph) loci of Drosophila melanogaster are each polymorphic for two electrophoretically detectable alleles. The frequencies of the Odh and Acph alleles have been analysed in populations sampled from up to a 40 ° latitudinal range in each of Australasia, North America and Europe/Asia. Odh S frequency is found to be significantly negatively associated with distance from the equator in all three zones. The relationship of Acph S frequency to distance from the equator is significant and negative in Australasia but neither significant nor consistent in sign in North America and Europe/Asia.
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  • 23
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    Theoretical and applied genetics 64 (1983), S. 97-101 
    ISSN: 1432-2242
    Keywords: Common wheat ; Triticum aestivum ; Electrophoresis ; Endosperm proteins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Total endosperm protein subunits, extracted from the common wheat cultivar Chinese Spring and from some of its aneuploid lines, were fractionated according to their molecular weight (MW) in an improved high resolution one-dimensional sodium dodecyl sulphate (SDS) polyacrylamide gel electrophoresis (PAGE). The resolution obtained by this method and, in particular, that of the high molecular weight (HMW) glutenin and gliadin subunits approached that of a previous report in which two-dimensional fractionation system based on charge and MW was used. In the cultivar Chinese Spring, 21 discrete protein bands were resolved and the chromosomes controlling many of them were either reconfirmed, or, in some cases, established. The advantages of this high resolution SDS PAGE technique are discussed.
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  • 24
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    Theoretical and applied genetics 67 (1983), S. 53-58 
    ISSN: 1432-2242
    Keywords: Aegilops umbellulata ; Genetics ; Lectin ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Each of the three genomes in hexaploid wheat controls the expression of a specific lectin in the embryo. The chromosomes which control their synthesis were determined using nullisomic-tetrasomic and inter-varietal chromosome substitution lines of ‘Chinese Spring’. All three wheat lectins were shown to be controlled by the homoeologous group 1 chromosomes. Using ditelosomic lines of ‘Chinese Spring’ the lectin genes could be localized on the long arms of chromosomes 1A and 1D. Inter-specific addition and substitution lines of Aegilops umbellulata chromosomes to ‘Chinese Spring’ indicated that chromosome 1U, which is homoeologous to the group 1 chromosomes of wheat, controls lectin synthesis.
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  • 25
    ISSN: 1432-2242
    Keywords: HMW glutenin subunit genes ; cDNA clones ; Tandem DNA repeats ; Chromosomal location ; Gene copy number ; Wheat ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary cDNA clones encoding wheat HMW glutenin subunits have been isolated from a cDNA bank made to poly A+ RNA from developing wheat endosperm var. Chinese Spring. One such clone, pTag 1290, has enabled us to identify the HMW glutenin mRNA species. The DNA sequence of this clone has been partially determined and it contains several tandem DNA repeats. The sequence is discussed in relation to the generation of the HMW glutenin subunit gene family. Analysis of the organization of the HMW glutenin sequences in the wheat genome revealed that the genes encoding HMW glutenin subunits exist in low copy number and are located on the long arm of each of the homoeologous group 1 chromosomes.
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  • 26
    ISSN: 1432-2242
    Keywords: Triticum aestivum ; T. timopheevii ; Wheat ; Photoperiod ; Vernalization ; Male sterility ; Alloplasmic hybrids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Studies were conducted to determine the influence of the male sterility-inducing cytoplasm of Triticum timopheevii (Zhuk.) Zhuk. on response of several common winter wheat (T. aestivum L.) nuclear genotypes to photoperiod and vernalization. Comparative studies of cytoplasmic substitution lines provide information on the role of the cytoplasmic genetic mechanism in growth and development. In the case of cytoplasmic male sterility-based hybrid production systems, ubiquity of sterility-inducing cytoplasm in derived hybrids warrants thorough characterization of its influence on plant phenotype. Factorial combinations of cytoplasm (T. timopheevii and T. aestivum), nuclear genotype, and photoperiod or vernalization treatments were evaluated under hydroponic conditions in controlled environment chambers. Interaction of cytoplasm, photoperiod, and nuclear genotype was significant in one or more experiments for days to anthesis and potential spikelet number, and interaction of cytoplasm, vernalization, and nuclear genotype was significant for days to spike emergence. Long day length was associated with increased percentage seed set in one study, but interactions of photoperiod and cytoplasm were not detected for percentage seed set. Interactions involving cytoplasm and photoperiod or vernalization were interpreted as evidence of the existence of genetic factors in cytoplsam of T. timopheevii which alter photoperiod or vernalization responses of alloplasmic plants relative to responses exhibited by euplasmic plants. Since photoperiod and vernalization responses are critical to adaptation, T. timopheevii cytoplasm can alter adaptability of T. aestivum. The specific effect would be nuclear genotype dependent, and does not appear to be of a magnitude greater than that induced by nuclear genetic variability at loci conditioning photoperiod or vernalization responses or other adaptation-determining characteristics. Normal multilocation/year testing of alloplasmic hybrids should therefore adequately identify zones of adaptation.
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  • 27
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    Theoretical and applied genetics 66 (1983), S. 77-86 
    ISSN: 1432-2242
    Keywords: Common wheat ; Triticum aestivum ; Electrophoresis ; Endosperm proteins ; Glutenins ; Gliadins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Endosperm protein subunits of 109 primitive and modern lines of hexaploid wheat, Triticum aestivum L. em. Thell., were fractionated by one-dimensional, high resolution, sodium dodecyl sulphate (SDS) polyacrylamide gel electrophoresis (PAGE). A wide range of both qualitative and quantitative variation was observed in the fractions of the high molecular weight (HMW) glutenin and gliadin subunits of the different lines. The qualitative variation was expressed in the number of subunits per fraction and in their molecular weight, as determined by the differential rate of migration. The quantitative variation was expressed in the differential staining intensity of several subunits. The widest variation was detected in the HMW glutenin and gliadin subunits controlled by chromosome 1B while a much smaller variation was observed in those subunits controlled by chromosome 1A and further smaller variation in the subunits controlled by 1D. Only a small number of subunits in both fractions was found to be controlled by chromosome 1A indicating that diploidization of endosperm protein genes in common wheat has been non-random. The genetic and evolutionary implications of these findings are discussed.
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  • 28
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    Theoretical and applied genetics 66 (1983), S. 1-7 
    ISSN: 1432-2242
    Keywords: Triticum aestivum ; Aegilops species ; Alloplasmic lines ; 2D gel electrophoresis ; Cytoplasmic inheritance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary In this first analysis the protein patterns obtained by two-dimensional gel electrophoresis of 8 day-old leaves from 18 alloplasmic wheat lines are compared. From 440 spots retained on the basis of their reproducibility, 36 proteins were observed to vary in different cytoplasms, allowing us to distinguish the T. aestivum cytoplasm from 5 Aegilops cytoplasms. Twenty-four of the 36 variable proteins could be structurally related to the large subunit of RuBPCase. Nuclear variation between 3 wheat varieties was observed for 14 proteins.
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  • 29
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    Protoplasma 115 (1983), S. 104-113 
    ISSN: 1615-6102
    Keywords: Cereals ; Embryo culture ; Triticum aestivum ; Wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Cell proliferation from the mature embryo of wheat occurs on a defined medium in the presence of 2,4-D. Unorganized growth is observed when the 2,4-D concentration is equal to or greater than 2 mg/l, but increasing levels of 2,4-D inhibit cell division. Cell divisions begin after 4 days in culture from parenchyma cells within and near the procambial tissues of the embryo axis. By day 8 continuous meristematic zones are formed in association with vascular tissues, and DNA synthesis and cell divisions are distributed throughout these zones. No morphological evidence exists to show that these zones consist of proliferating root primordia, which are formed only after the level of 2,4-D falls below some critical concentration. When the concentration of 2,4-D is lowered, the meristematic zones first become dissected and then give rise to many root meristems.
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  • 30
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    Euphytica 32 (1983), S. 217-223 
    ISSN: 1573-5060
    Keywords: Hexaploid triticale ; Secale cereale ; rye ; Triticum aestivum ; wheat ; heterochromatin ; chromosome association
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary In the hexaploid triticale (× Triticosecale Wittmack) cultivar Rosner chromosome 2R lacks the prominent heterochromatic bands of both telomeres. This modified 2R chromosome is capable of pairing in a high frequency with wheat chromosomes. It is hypothesized that the accumulation of heterochromatin at the telomeres of rye chromosomes may have contributed to the isolation of the wheat and rye genera by inhibiting pairing between wheat and rye chromosomes.
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  • 31
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    Euphytica 32 (1983), S. 431-438 
    ISSN: 1573-5060
    Keywords: Hordeum vulgare ; barley ; Triticum aestivum ; wheat ; T. turgidum ; durum wheat ; X Triticosecale ; triticale ; salt tolerance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Saline soils are typically very patchy in their salinity. The yield of crops growing on them is similarly patchy. This paper argues that because most of the yield from such soils comes from the least saline areas, the best breeding strategy for improving the overall yield of crops growing on them is to select for high yield on non-saline soils. This conclusion derives from comparing the effects that four different breeding goals, namely: (1) a 10% increase in yield on non-saline soils, (ii) a 20% increase in the threshold salinity that first reduces yield, (iii) a doubling of yield at an electrical conductivity of the saturation extract (ECe) of 20 dS/m and (iv) a combination of (i) and (iii), would have on total yield. The effects of achieving these goals in barley, common wheat, durum wheat and triticale in fields exhibiting different salinities are predicted from actual yields of these species grown on different salinities in the field.
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  • 32
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; wheat ; kernel color ; protein content ; inheritance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Utilization of high-protein hard red wheat germplasm in breeding high-protein hard white winter wheats for the U.S. Great Plains raised concern regarding possible genetic relationships between kernel color and protein content. Segregating F3 and F4 populations from reciprocal crosses and backcrosses involving high-protein hard red winter wheat cultivar Plainsman V and normal-protein hard white winter wheat line KS75216 were examined. Nonsignificant regression and correlation coefficients in the F3 generations of KS75216/Plainsman V, KS75216//KS75216/Plainsman V and Plainsman V//KS75216/Plainsman V indicated the absence of genetic relationships between kernel color and protein content. Therefore, despite the presence of genes for protein content and kernel color on the same chromosomes (3A, 3B and 3D), kernel color and protein content appeared as independent traits. A small but significant negative relationship between white kernel color and high protein in Plainsman V/KS75216 was attributable to the possible presence of alien genetic material in the parentage of Plainsman V. Chi-square tests indicated that Plainsman V is a mixture of genotypes for kernel color; most genotypes carry two dominant genes for red color and a few carry one or three. Genetic control of grain protein appeared to be complex. Partial dominance for high protein was indicated in the F3 generation but a generally continuous distribution and transgressive segregation also suggested other genes functioned additively. Heritability estimates by parent-offspring (F3-F4) regression were sufficiently high to ensure genetic progress in the selection of high-protein lines in the red x white wheat crosses. We concluded that development of high-protein cultivars is as feasible for white wheats as for red wheats.
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  • 33
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    Euphytica 32 (1983), S. 299-310 
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; bread wheat ; ear colour ; glume colour ; genetics ; linkage ; chromosomal location ; geographical distribution ; homeoallelic genes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary A summary of the brown ear character of bread wheat is presented. In most varieties this character is conditioned by a (semi)dominant gene identified as Rg on 1BS. This gene seems to be widespread, from the viewpoint of evolution, probably because it is an ‘old’ gene. There are no indications that the presence of the gene and hence the presence of a brown ear is advantageous or disadvantageous to the carrier wheat plant. Some linkage relations are described. More research is needed to establish whether all varieties with one gene for brown ear carry Rg, to investigate the varieties with a non-monogenic genetic system and to identify more associations between brown ear and other characters. It should also further be investigated whether within T. spelta another gene for brown ear is present and, if so, whether this gene is on chromosome 1AS and linked to Hgl, the gene for hairy glume.
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  • 34
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    Euphytica 32 (1983), S. 743-748 
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; wheat ; plant physiology ; plant breeding ; Australia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Major changes in the behaviour of the Australian wheat crop over the last one hundred years have been associated with three major gene groupings. The significance of major genes in monitoring response to vernalization, photoperiod and gibberellin, reveals a more optimistic future for breeding programmes where simple genetic and physiologic studies are integrated within those programmes. A revised classification of growth habit is presented in the appendix.
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  • 35
    ISSN: 1573-5036
    Keywords: Acetic acid ; Inhibition ; Wheat growth ; Tillering ; Root growth ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Studies were conducted to determine the effect of and duration of the effect of alliphatic acids on winter wheat (Triticum aestivum L.) seedling root growth, shoot growth, and tillering. Winter wheat seedlings grown in contact with unbuffered solutions of 2 mM or greater acetic or 0.5 mM or greater propionic or butyric acid for 3 days showed decreased root and, in general, shoot growth. Buffering the medium partially alleviated the problem. Removing the seedling from the acid medium and growing it in a nutrient medium resulted in accelerated root growth, compared with the control, while shoot growth was permanently inhibited during this study. Seedling wheat, grown with one root in contact with concentrations of acetic acid ranging from 0–16 mM and the other roots in aliphatic acid-free medium, grew at the same rate as the control. Seedling wheat grown for 3 days in 2 and 4 mM acetic acid medium showed a more rapid formation of the first stem tiller (T1) than did the control. Concentrations of 6 and 8 mM acetic acid appeared to delay T1 tiller formation through the first 18 days after germination, while only 10 mM acetic acid reduced T1 tiller formation by 30% 20 days after germination. The second stem tiller (T2) was not affected by previous exposure to acetic acid. The results of these laboratory studies indicate that short-term exposure of seedling winter wheat to short-chain aliphatic acids can result in permanent shoot and tiller damage and not in permanent root damage as previously thought. These results could explain the poor performance of no-till seeded winter wheat when growing through heavy crop residues that are producing shortchain aliphatic acids during decomposition.
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  • 36
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    Plant and soil 70 (1983), S. 391-402 
    ISSN: 1573-5036
    Keywords: Intercropping Lupins ; Lupinus albus ; Manganese ; Nitrogen ; Phosphorus ; Triticum aestivum ; Wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Significant interactions between wheat and lupins occur below ground and wheat intercropped with lupins has access to a larger pool of available P, Mn and N than has wheat grown in monoculture. This suggests that the wheat is able to take up nutrients produced or made available by lupins grown in association with it.
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  • 37
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    Plant and soil 71 (1983), S. 463-467 
    ISSN: 1573-5036
    Keywords: Anion uptake ; Barley ; Hordeum vulgare ; Mycorrhiza ; Phosphorus ; pH Rhizosphere ; Triticum aestivum ; Wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary In two field experiments sown in 1982 to test the effect of vesicular-arbuscular mycorrhizas (VAM) on growth and phosphorus nutrition of (i) spring wheat and spring barley, (ii) winter wheat and winter barley, we measured the concentrations of the major cation (K+, Ca2+, Mg2+ and Na+) and anions (Cl−, SO4 2−, H2PO4 − and NO3 −) in shoot tissue. In all cases the sum of the anion concentrations (ΣA) was increased strongly by mycorrhizal infection but not by P additions, confirming earlier observations2 on spring wheat. The concentration of total cations (ΣA) was generally reduced by P additions, hence P and VAM both reduced the cation excess (ΣC−ΣA) but by different mechanisms. These results suggest that increased uptake of anions by plants with VAM may be a general phenomenom which would have important implications for the elemental composition of crops. The effect may also be manifested by other types of mycorrhizal association.
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  • 38
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    Plant and soil 75 (1983), S. 51-61 
    ISSN: 1573-5036
    Keywords: Aggregate fractions ; Fatty acids ; Long-term rotation ; Triticum aestivum ; Water-stable aggregates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Three non-replicated, unfertilized, dryland grain rotations—continuous wheat, wheat-fallow, and wheat-wheat-fallow—were established in 1912 on a Dark Brown Chernozemic (Typic Haploboroll) soil. The effect of long-term cropping on the chemical constituents of total water-stable aggregates was assessed. There was a loss in percentage of total water-stable aggregates and a shift in aggregate size distribution with time. Together with an increase in the 100 μm diameter fraction, there was an increase in the sand component of this fraction. These sand particles are probably held together by alkaline-soluble, acid-insoluble organic matter. Organic carbon, polysaccharides, polyuronides, phenols, and chloroform/methanol-extractable organic matter were all associated with the 〉250 μm diameter fractions. Although the aggregates had generally the same suite of aliphatic carboxylic acids, the relative proportions changed with cultivation.
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  • 39
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    Euphytica 32 (1983), S. 593-600 
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; bread wheat ; Triticum durum ; durum wheat ; Secale cereale ; inbred lines ; intergeneric crossability ; embryo development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Crossability and embryo development were studied in the crosses of one Triticum aestivum and three T. durum genotypes with nineteen rye inbred lines. Parental wheat and rye genotypes exerted a significant influence on the characters seed set, number of seeds containing embryos and viable plantlets obtained from embryo culture. It was established that the common winter wheat cultivar Götz is of intermediate crossability. The rye inbred lines varied substantially in their capacity to fertilize several wheat genotypes. Interactions between wheats of different crossability classes and their seed set with rye lines were detected. Significant correlations were obtained between seed set and viable plantlets recovered in vitro.
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  • 40
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; wheat ; protein content ; grain yield ; mixing time ; soil-borne mosaic virus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The wheat (Triticum aestivum L.) cultivar Lancota has genetic potential to produce grain with higher protein content than most other cultivars grown in the hard winter wheat region. It has not consistently expressed full potential for grain protein content outside its area of development. Experiments were conducted to determine genetic variability for grain protein content in Lancota and to utilize that variability to select genotypes with high grain protein content. Approximately 1600 lines were screened to 37 high-protein selections that varied in yield, test weight, flour mixing time, blooming date, height, and reaction to wheat soil-borne mosaic virus (WSBM). Nine promising selections (KS80476, KS80478, KS80480, KS80488, KS80490, KS80491, KS80497, KS80499, and KS80500) had grain protein advantage over Lancota of 0.5 to 1.0% and equalled or exceeded Lancota in yield or test weight. Those selections were resistant to WSBM and satisfactory or better in mixing properties than Lancota. The highest protein selection (KS80496) had a mean protein advantage of 1.5% over Lancota but exhibited a short mixing time of 1 7/8 min. The absence of correlation between some years indicated strong environmental influence on protein content. We concluded that adequate genetic variability existed in the high-grain protein cultivar Lancota to select lines that express the high protein potential better than the original cultivar outside its area of development.
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  • 41
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; wheat ; linkage drag ; seedling resistance ; Puccinia graminis tritici ; stem rust ; Puccinia recondita ; leaf rust ; Puccinia striiformis ; yellow rust ; stripe rust
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary To determine whether linkage drag had occurred during the breeding of near isogenic lines (NILs) of wheat, 176 lines involving 11 sets of NILs, their recurrent parents and some of their donors were tested for seedling reaction to stem rust (4 races), leaf rust (3 races) and yellow rust (3 races). From the results, six cases were identified in which linkage drag may have played a role. More research is needed to prove clearly that linkage is involved. Nevertheless, the results suggest that linkage drag is a fairly common phenomenon.
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  • 42
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; wheat, glutenin ; high-molecular-weight subunits ; SDS-PAGE ; SDS-sedimentation test ; baking quality selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The high-molecular-weight subunit composition of glutenin is regulated by genes on the long arm of the homoeologous group 1 chromosomes. Evidence is presented that in general the bread-making quality of wheat cultivars containing the subunits 3+10 coded for by chromosome 1D or the subunit 2* coded for by chromosome 1A is higher than that of cultivars containing their allelic counterparts the subunits 2+11 or subunit 1 and the null form respectively. Besides it is shown that the positive effects of the subunits 3+10 and subunit 2* are additive.
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  • 43
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; bread wheat ; Triticum turgidum ; Hordeum vulgare ; barley ; chemotypes ; electrophoresis ; variation ; prolamines ; gliadins ; hordeins ; electrophoregram ; genetic resources
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Polyacrylamide gel electrophoresis (PAGE) of storage proteins (prolamines) was used to screen 64 landraces of wheat and barley from Nepal and the YemenArab Republic and two cultivars for comparison. Altogether 3168 single seeds were examined and the advantages gained by using the vertical slab gel method were recognised. The extent of variation present within populations of landraces could be assessed easily and rapidly using the methods described. Differences in ploidy levels of wheats were detected by PAGE and investigated. Suggestions are made for improvements in sampling strategies in hilly terrain.
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  • 44
    ISSN: 1573-1561
    Keywords: allelopathy ; ferulic acid ; no-tillage ; prickly sida ; common ragweed ; weed control ; 2-methoxy-4-ethenylphenol ; carboxylic acid ; phenol ; morning glory ; Ipomoea lacunosa ; wheat ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract This study was conducted to determine if well-known phytotoxic effects of plant residues on crop growth could also be responsible for observed reductions of certain weed species in no-till cropping systems. An aqueous extract of field-grown wheat (Triticum aestivum L.) reduced the germination and root length of pitted morning glory (Ipomoea lacunosa L.) and common ragweed (Ambrosia artemisiifolia L.). Phytotoxicity was increased by about 70% when bioassays with the wheat extract on morning glory and ragweed were conducted in the presence of light. Phytotoxic substances were extracted from wheat with 2 N NaOH. The hydrolyzed extract was fractionated by thin-layer chromatography (TLC). The compound isolated by TLC having the greatest inhibitory effects on morning glory germination was identified using mass spectrometry and determined to be ferulic acid (4-hydroxy-3-methoxycinnamic acid). Ferulic acid at 5 × 103 M inhibited the germination and root length of morning glory 23 and 82%, respectively, and prickly sida (Sida spinosa L.) with carpels 85 and 82%, respectively. Crabgrass (Digitaria sanguinalis L.) germination was inhibited 100%. Ferulic acid had no effect on ragweed or prickly sida without carpels. Morning glory root and shoot biomass were reduced 52 and 26%, respectively, when morning glory was grown in sand and watered with a 5 × 103 M solution of ferulic acid. Ferulic acid in the presence of prickly sida seed carpels was found to undergo decarboxylation, forming a styrene derivative, 2-methoxy-4-ethenylphenol. The more phytotoxic styrene compound was produced by a bacterium isolated from the carpels of prickly sida seed. The study showed that ferulic acid and other compounds may indeed play a role in reducing the growth of certain weeds in no-tillage cropping systems.
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  • 45
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    Plant and soil 74 (1983), S. 101-109 
    ISSN: 1573-5036
    Keywords: Crop residue ; Root growth ; Shoot growth ; Soil types ; Temperature ; Triticum aestivum ; Wheat germination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Two controlled environment experiments were conducted to examine the germination and early growth of wheat (Triticum aestivum L. cv. Songlen) growing under crop residues of rape, sorghum, field pea and wheat. Additional treamments also included were soil type (Lithic Vertic Ustochrept and Plinthustalf) and temperature (8°C and 24°C to simulate winter and autumn sowing conditions). At low temperature, wheat and sorghum residues produced the most adverse effects on germination with all residues reducing emergence at high temperatures. Shoot lengths were also reduced by most residues at high temperatures whilst root lengths and shoot and root dry weights were unaffected by residue treatments. These results suggest major phytotoxic effects of residues during early growth (up to 14 days after sowing) with, in general, few interactions with soil type or temperature.
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  • 46
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    Plant and soil 74 (1983), S. 229-235 
    ISSN: 1573-5036
    Keywords: Barley ; Hordeum vulgare ; Mineral composition ; Na−K interaction ; Solonetzic soil ; Solonetz-Solod sequence ; Triticum aestivum ; Wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The growth and mineral composition of barley and wheat was measured across sequences of Solonetz and Solod soils. Growth of both species, along with root penetration was reduced on the Solonetz compared to the Solod soil. Mineral composition of the foliage and roots indicated that a Na−K interaction was present for the barley across the Solonetz-Solod sequences. Such factors were considered to be characteristics of soil—plant relationships on Solonetzic soils.
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  • 47
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; wheat ; chromosome substitution lines ; vernalization ; ear emergence ; basic development rate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The influence of vernalization on days to ear emergence in hexaploid wheat (Triticum aestivum L. em. Thell.) was examined in five Chinese Spring/Thatcher (CS/T) chromosome substitution lines. CS/T 5A and 5D were similar to normal Chinese Spring in days to ear emergence after all periods of vernalization while CS/T 3B and 5B were similar after some, but significantly earlier after other periods of vernalization When compared with Chinese Spring. In both the unvernalized condition and when vernalization did not limit development rate CS/T 7B was faster to ear emergence than Chinese Spring. These results are discussed in relation to the known chromosomal and genetical control of vernalization response.
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  • 48
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    Euphytica 32 (1983), S. 225-230 
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; wheat ; shattering ; awns ; height
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Temporal changes in shattering losses of 14 wheat (Triticum aestivum L.) genotypes were studied in an irrigated environment. The lines ranged in height from 68 to 98 cm; eight lines were fully awned while five were not. Shattered kernels were gathered at weekly intervals for 6 wk; samping commenced at 30 to 40% kernel moisture and continued for 3 wk beyond harvest ripeness (14.5% moisture). Shattering loss, expressed as a percentage of yield, ranged from 3.25 to 17.3% over the 6 wk period. Awnedness was not a factor in shattering susceptibility of the genotypes studied. Both the most and least shattering resistant lines in this study were awnless. There was a nonsignificant correlation between shattering losses and plant height. It was concluded that a single quantitative measurement of shattering loss at or after harvest ripeness (14.5% moisture) would provide an adequate measure of shattering susceptibility.
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  • 49
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    Euphytica 32 (1983), S. 241-255 
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; wheat ; physiology ; grain yield ; inheritance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Post anthesis physiological characters were examined in four genotypes and a diallel set of their progenies. Variation in total carbon uptake by photosynthetic tissue above the flag leaf node was primarily related to leaf area and ear size differences during the early grain filling period. Flag leaf apparent photosynthetic rates during the late grain filling period were closely correlated with flag leaf chorophyl levels. During the period of rapid growth, genotypes differed in the proportion and total quantity of current assimilate translocated to the grain. Total rather than proportional translocation was correlated with grain number and grain yield. Differences in total grain protein were primarily related to total plant nitrogen at anthesis and secondarily to the proportion of this nitrogen translocated to the grain. The level of post anthesis nitrate reductase activity decreased with increasing flag leaf age, but genotypic differences were not closely related to differences in total grain protein contents. Significant general combining ability effects were found for flag leaf chlorophyll levels, flag leaf photosynthetic rates at higher illuminances during the late grain filling period, total plant carbon uptake, total ear carbon uptake, and proportional carbon translocation to the grain. A preponderance of significant general combining ability variances suggests that additive gene action is of particular importance in the inheritance of these physiological characters.
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  • 50
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    Euphytica 32 (1983), S. 257-271 
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; bread wheat ; Triticum durum ; durum wheat ; Triticum compactum ; collection ; germplasm ; land-races ; local varieties
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Wheat has traditionally been grown by the Beduin population in the semi-arid (150 to 200 mm, mean total annual rainfall) northern Negev region of Israel. A collection was made in this area (the size of which is 150 km2) from small (0.1 to 0.5ha) fields of mixed wheat, resulting in 1553 collected spikes. Each spike was planted in a 1 m row at Bet Dagan, and grown under favorable conditions. Qualitative and quantitative data were collected from each row. Qualitative data were submitted to hierarchial clustering and the results were compared with published information on the identification, classification and distribution of the land-races of wheat in the Middle East. Triticum durum was represented in 84% of the collection. It was clustered into 22 populations, identified as 11 known varietas of T. durum. They were aggregated into five groups, similar to groups of old varieties recognized by Jacubziner (1932). While 38.5% of the collection consisted of T. durum groups villosa and sinaica, aboriginal to the northern Negev, it included also forms similar to several land-races found in the past in other parts of the Middle East. Each of the populations, and the durum collection as a whole, was very diverse for the quantitatively measured plant attributes. Triticum aestivum was represented in 15.6% of the collection, clustered into six populations. Most of the common wheat accessions were analogous to the old locally grown variety Hirbawi. Triticum compactum was represented in only eight accessions. The collection is now being evaluated as a potential genetic resource for durum wheat breeding.
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  • 51
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; bread wheat ; grains ; dry matter and nitrogen ; distribution within ear ; plant height
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Distribution and accumulation of dry matter (d.m.) and nitrogen (N) were investigated within ears of a semidwarf, a gigas, and a normal wheat genotype grown under controlled environments. A high harvest index was linked with a small pre-anthesis N-storage (and vice versa) but this did not affect N amounts in grains because of compensation by prolonged N uptake during grain filling. N distribution within and between spikelets roughly paralleled that of d.m. Nevertheless, the two processes appeared to be rather independent as became evident from comparisons of the time courses in and between the genotypes. Final distribution of d.m. and N within and between spikelets mainly depended on different rates during the linear phases of accumulation and less on the duration. Maximum of d.m. and N weights per grain as well as maximum of grain number were observed in spikelets below the middle of the ear axis. This ‘submedian dominance’ suggested a pre-anthesis determination of the accumulation potential of grains in different spikelets. N percentage within spikelets disclosed that N accumulation was hampered more than that of d.m. in those positions unfavourable to the latter process. This principal pattern was not affected by genotypes in spite of considerable differences in numbers and weights of grains.
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  • 52
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    Euphytica 32 (1983), S. 575-584 
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; wheat seedlings ; Triticum sp. ; Septoria nodorum ; glume blotch disease ; components of partial resistance ; multivariate analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Components of partial resistance of wheat seedlings to Septoria nodorum were measured in a glasshouse. Incubation period, infection frequency, latent period, lesion size, lesion cover, necrosis and unit spore production were recorded on 41 Triticum genotypes. There was no clear evidence of associated variation in components and multivariate analyses were used to elucidate such relationships. Factor analysis indicated that pathogen-induced necrosis, related possiby to toxin susceptibility, and unit spore production were major components of partial resistance to S. nodorum. Principal component analysis was used to characterise genotypes: associated with a continuous general resistance could be a high level of pathogen-induced necrosis or a high unit spore production, but rarely both in the same genotype.
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  • 53
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    Cellular and molecular neurobiology 3 (1983), S. 143-149 
    ISSN: 1573-6830
    Keywords: electroretinogram ; visual mutants ; visual sensitization ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary 1. Mutations at thestoned locus ofDrosophila melanogaster produce a reversible temperature-sensitive debilitation. At permissive temperatures they also exhibit an unusual jump response to a light-off stimulus. 2. An increase in the amplitude of the off-transient of the electroretinogram (ERG) is associated with this abnormal jump. Both the jump response and the increased amplitude of the off-transient are shown to be dependent on the duration of the light pulse prior to the light-off stimulus. 3. Instoned flies which are light adapted, the jump response, as measured by recording from the indirect flight muscles, is seen to habituate with increasing light-off frequency. This habituation corresponds to the decrease in the amplitude of the off-transient that also occurs with high-frequency stimulation. 4. Another visual mutanttan, removes the off and on-transients of the ERG. 5. The combining of thestoned mutation withtan in thetan, stoned double mutant results in the loss of the jump behavior as well as the partial restoration of the off-transient to an otherwisetan-like ERG. The relationship between the increase in the amplitude of the off-transient instoned flies and the eliciting of the jump response is discussed.
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  • 54
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    Cellular and molecular neurobiology 3 (1983), S. 127-141 
    ISSN: 1573-6830
    Keywords: cyclic adenosine monophosphate ; calmodulin ; phosphorylation ; visual mutants ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary 1. Protein IV from synaptosomal fractions ofDrosophila heads is phosphorylatedin vitro by an endogenous cyclic adenosine monophosphate (cAMP)-dependent protein kinase. Thein vivo phosphorylation of this protein is affected by light. 2. Two visual mutants,tan andstoned, exhibit altered levels ofin vivo phosphorylation of protein IV. Thetan strain shows depressedin vivo levels of phosphorylation of protein IV, whereasstoned shows an increase in thein vivo level of phosphorylation of this same protein. 3. Protein D is phosphorylatedin vitro by an endogenous Ca2+/calmodulindependent protein kinase and has a molecular weight identical to that of protein IV. Thestoned mutant strain shows an increase in thein vivo level of phosphorylation of protein D. 4. The data presented here suggest that the phosphorylation of protein IV, and perhaps D, may play a role in the early processing of visual information in the fly.
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  • 55
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    Cell & tissue research 228 (1983), S. 497-509 
    ISSN: 1432-0878
    Keywords: Drosophila ; Larval salivary glands ; Nuclear “oval bodies” ; Annulate lamellae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Morphological data are presented concerning the single-membrane-bound vesicles (“oval bodies”) associated with the nuclear envelopes of larval salivary gland cells of Drosophila. Data are also presented concerning the existence of cytoplasmic annulate lamellae in these same cells. The mode of formation of these structures, as well as the relationships between them and with other cytoplasmic organelles are described. The possible functional significance of these phenomena is discussed.
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  • 56
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    Cell & tissue research 233 (1983), S. 305-317 
    ISSN: 1432-0878
    Keywords: Freeze fracture ; HVEM ; Retina ; Optic neuropile ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The developmental mutant of Drosophila (ora JK84) is characterized by nonfunctional photoreceptor cells (R1–6), while the R7/R8 cells are normal. A fundamental question is: Does the near absence of photosensitive membranes inhibit development of the Rl-6 axons and their synapses at the other end of the cell? The retina and first optic neuropile (lamina ganglionaris) were examined with freeze-fracture technique and high voltage electron microscopy. R1–6 have reduced rhabdomere caps; rhabdomeric microvilli have about 50% of the normal diameter and 20% of the normal length. Affected cells exhibit prominent vacuoles which appear to communicate with some highly convoluted microvillar membranes. Almost no P-face particles (putative rhodopsin molecules) are present in the R1–6 rhabdomeres, and particle densities are lower in R7 than previously reported. Near the rhabdomere caps, microvilli of R1–6 are fairly normal, but at more proximal levels they are greatly diminished in length and changed in orientation, while at still more proximal levels they are lost. R1–6, R7, and R8 axons from each ommatidium are bundled into normal pseudocartridges beneath the basement membrane. No abnormalities are found in the lamina ganglionaris, and all synaptic associations as well as the presumed “virgin” synapses (of R1–6) appear normal. No glial anomalies are present, and R7/R8 axons project through the lamina in the usual fashion. These fine structural findings are correlated with known electrophysiological, biochemical, and behavioral correlates of both sets of photoreceptors (R1–6, and R7/R8).
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  • 57
    ISSN: 1432-0878
    Keywords: Drosophila ; Oogenesis ; Colchicine ; Microtubules ; Sterility
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Adult female fruitflies exposed to colchicine admixed to the culture medium show a series of dosage-related abnormalities that affect oogenesis and may induce sterility. Among the effects observed were decreased fecundity and hatchability of laid eggs, formation of oocytes lacking chorionic appendages, abnormal distribution and diminution in number of yolk spheres, inhibition of oocyte growth and abnormally located oocyte nuclei. Potentially the most significant effect was the development of egg chambers which contained the normal complement of 16 cells but in which all the cells had the nuclear morphology of nurse cells. The approach provides for the first time an experimental means to divert a potential oocyte into the developmental pathway of the nurse cell in a wild-type fly, and hence should be helpful in the elucidation of factors which control oocyte and nurse cell differentiation. In addition, the results serve to expand the usefulness of oogenesis in Drosophila as a model system for the evaluation of drug-induced metabolic-morphologic abnormalities.
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