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Theory and recent reviews state that greater genetic and phenotypic variation should be beneficial for population abundance and stability. Experimental evaluations of this prediction are rare, of short duration and conducted under controlled environmental settings. The question whether greater diversity in functionally important traits stabilizes populations under more complex ecological conditions in the wild has not been systematically evaluated. Moths are mainly nocturnal, with a large variation in colour patterns among species, and constitute an important food source for many types of organisms. Here, we report the results of a long-term (2003–2013) monitoring study of 115 100 noctuid moths from 246 species. Analysis of time-series data provide rare evidence that species with higher levels of inter-individual variation in colour pattern have higher average abundances and undergo smaller between-year fluctuations compared with species having less variable colour patterns. The signature of interspecific temporal synchronization of abundance fluctuations was weak, suggesting that the dynamics were driven by species-specific biotic interactions rather than by some common, density-independent factor(s). We conclude that individual variation in colour patterns dampens population abundance fluctuations, and suggest that this may partly reflect that colour pattern polymorphism provides protection from visually oriented predators and parasitoids.  相似文献   
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Homogeneous population structure in a migrant Lepidoptera, Agrotis ipsilon. Light trapping of Agrotis ipsilon (Lepidoptera, Noctuidae) on various passes of the Alps and Pyrénées exhibited wide range movements between overwintering and aestivation areas. Electrophoretic analysis of samples taken in the Cantons of Vaud and Tessin (Switzerland), in the Rhône Delta (Southern France), and on passes of the Alps and Pyrénées, showed a great temporal and spatial homogeneity of allele frequencies (Fst values ranging from 0.002 to 0.013, and genetic distances from 0 to 0.004). These results support the hypothesis of a high level of gene flow. However, the occurrence during some years of high Fis values, might be explained by mixtures of populations that had undergone selection or went through a bottle-neck.  相似文献   
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苹果园鳞翅目夜蛾科DNA条形码鉴定   总被引:1,自引:0,他引:1       下载免费PDF全文
为了检验DNA条形码在鳞翅目夜蛾科蛾类鉴定中的可行性,本文对采自北京昌平苹果园内的夜蛾科14种71头蛾类标本分别提取了DNA,并扩增了线粒体cox1及核基因28S,利用系统发育树、遗传距离、阈值等方法进行了鉴定和比较分析。同时,检验了目前BOLD系统的鉴定成功率。实验表明,基于cox1基因和BOLD系统的鉴定成功率达到了100%,而基于28S则很低,为64.8%。用不同方法构建的系统发育树,鉴定结果均相同。93%的种内遗传距离小于1%,94%的种间遗传距离为大于3%,种内种间的遗传距离形成明显的3%阈值现象。  相似文献   
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Summary Cell lines from selected lepidopteran species were established for the overall purpose of use in baculovirus production. A total of 36 new cell lines from 10 lepidopteran species were generated, including cell lines from a pyralid, the European corn borer,Ostrinia nubilalis, a plutellid, the diamondback moth,Plutella xylostella, as well as eight noctuids: the black cutworm,Agrotis ipsilon, the celery looper,Anagrapha falcifera, the velvetbean caterpillar,Anticarsia gemmatalis, the corn earworm,Helicoverpa zea, the tobacco budworm,Heliothis virescens, the beet armyworm,Spodoptera exigua, the fall armyworm,Spodoptera frugiperda, and the cabbage looper,Trichoplusia ni. Tissues used for cell line establishment included fat bodies, ovaries, testes, or whole embryos/larvae/pupae. All the cell lines were subcultured numerous times, characterized by isoenzyme analysis and/or deoxyribonucleic acid amplification fingerprinting using polymerase chain reaction, and stored in liquid nitrogen. Many of the cell lines were adapted to grow in serum-free medium, with cell lines fromA. ipsilon andH. virescens being adapted to suspension culture, using shaker flasks. The potential use for these cell lines in baculovirus production is discussed. All programs and services of the U.S. Department of Agriculture are offered on a nondiscriminatory basis without regard to race, color, national origin, religion sex, age, marital status, or handicap.  相似文献   
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In a laboratory flight tunnel, mated female, unmated female, and male adult cabbage loopers, Trichoplusia ni (Hübner), exhibited chemically mediated anemotaxis (attraction) in response to intact potted cabbage plants (Brassica oleracea L.), leading to contact with the plant. Similar attraction responses were also observed by mated females to potted soybean (Glycine max (L.)), tomato (Lycopersicon esculentum Miller), and celery (Apium graveolens L.) plants in noncompetitive comparisons. Mated females, unmated females, and males flew to cabbage plants throughout the scotophase. Response rates for mated females were higher than for unmated females and males. Mated female cabbage loopers were attracted by odors of cabbage, soybean, tomato, or celery piped into a flight tunnel from single plants held in glass jars and not to odors of the non-host plant Setcreasea purpurea, or to humidified air. They were also attracted to water washings of cabbage at dosages of 0.4 to 2.0 gram equivalents, when presented on cotton dental wicks in the flight tunnel.  相似文献   
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When precocene II was fed to last instar larvae of Heliothis zea, it caused significant reductions in the calculated rate of growth, rate of nutrient assimilation, and conversion of ingested and digested food to body mass. No change in the rate of food consumption occurred but respiration was significantly higher. Transport of the nutrient [1-14C] linoleic acid across midgut tissue was hindered when larvae were fed precocence II. There was also a precocene-induced change in the apical (luminal) morphology of midgut cells, including absence of the glycocalyx and loss of the microvillar absorptive surface. The influence of precocene II on the midgut physiology and metabolic processes in last instar larvae of H. zea may account for the observed reduced growth and delayed development. © 1992 wiley-Liss, Inc.  相似文献   
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本文用主成分分析法对夜蛾科卵的分类性状进行定量分析,用以说明各主成分的生物含义和各变量对分类的重要性.  相似文献   
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