共查询到20条相似文献,搜索用时 46 毫秒
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From the first test cross progenies of control (no larval transfers; no ethyl methanesulphonate), physical stress (two larval
transfers; no ethyl methanesulphonate) and 0.75% ethyl methanesulphonate (two larval transfers; 0.75% ethyl methanesulphonate)-treated
F1 (Oregon K +/dumpy black cinnabar, dp b cn) males ofDrosophila melanogaster, respectively, 6,10 and 52 wild-looking first test cross males were again test crossed to obtain second generation. The overall
percentages of male recombination detected in the second test cross progenies, in the three sets of experiments, were statistically
the same as those in the first test cross progenies. Thus the enhanced male recombination caused by physical stress (with
or without ethyl methanesulphonate) was transmitted to next generation. Non-reciprocal male recombination was observed indp b but not inb cn region in both first and second test cross progenies. Three abnormalities, (i) production of wild-type flies in majority
overdp b cn type, (ii) Non-Mendelian segregation atdp b andcn loci and (iii) sex-ratio differences fordp bcn and +b cn types observed in test cross progenies of F1 males ofDrosophila melanogaster were transmitted to next generation when induced with 0.75 % ethyl methanesulphonate but not when these abnormalities were
induced with physical stress. The data suggest possible association of non-reciprocal male recombination, segregation distortion
and sex-ratio imbalance inDrosophila melanogaster. In fact these may be representing different aspects of the same phenomenon 相似文献
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Leo S. Luckinbill Michael J. Clare Walter L. Krell William C. Cirocco Paula A. Richards 《Evolutionary ecology》1987,1(1):37-46
Summary Although many different physiological and biochemical changes characterize the process of senescence, little is understood of the genetic elements that determine its age of onset. We provide here the first estimates of the number of genetic factors that extend longevity inDrosophila melanogaster. Life span was measured in F1, F2 and backcrosses of true-breeding long and short-lived stocks ofD. melanogaster, established by selection. Estimates of the number of effective factors delaying senescence range from about 0.3 to 1.5, indicating control by a single factor. The distribution of longevity shows this to arise as selection acts on the short-lived parental stock. Life span is extended at the cost of early fecundity. 相似文献
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Morphology of transcription units inDrosophila melanogaster 总被引:1,自引:1,他引:0