棉蚜(Aphis gossypii)种群寄主分化和季节分化的微卫星引物PCR研究

通过对棉蚜群体进行室外观察、室内培养和分子遗传标记的DNA多态性分析（用3个微卫星序列为引物进行PCR）等研究，结果表明：1、冬寄主（木槿、石榴和花椒）上棉蚜种群分化较小（种群相似笥指数在0.833-0.917之间），而冬寄主种群和夏寄主（棉花和南瓜）种群之间有较大的分化（种群相似性指数在0.589-0.756之间）。2、棉蚜自然种群是由体色不变的生物型（干母为黄色，其后代始终为黄色）和体色可变型生物型（干母为绿色，其后代有绿色和黄色两种体色）组成的混合种群。3、黄色小型蚜（伏蚜）来源于混合类群，但主要来自绿色干母多代选择分化的黄色后代，也有小部分可能来处在干母黄色的体色不变型。

Microsatellite primer-PCR studies on the population differentiation of Aphis gossypii in relation to host plants and seasons

The present study investigated the differentiation of Aphis gossypii in relation to host plants and seasons This analysis, based on field investigation, lineage breeding and microsatellite primer PCR, showed that populations of A gossypii from three overwinter host plant species, Hibiscus Hibiscus syriacus , Pomegranate Punica granatum and Chinese prickly ash Zanthoxylum simulans , were closely related to a pair wise similarity index ranging from 0 833 to 0 917, suggesting a low level of differentiation among them But a high level of differentiation was found between the populations from overwinter hosts and summer hosts, cotton Gossypium hirsutum and pumpkin Cucurbita pepo , pair wise similarity index ranging from 0 589 to 0 756 The field population of A gossypii may be consist of two genetically determined body colour forms, i e unchangeable yellow form and changeable green form The former is always yellow both in fundatrix and its parthenogenetic offsprings, but in the latter, green fundatrix can produce both green and yellow offsprings The dwarf forms of A gossypii on cotton in summer may come from both green fundatrix and yellow one, but the majority of them may come from the former