Wing Polyphenism Study In Cotton Aphid, Aphis Gossypii,and DsRNA Effect On Non-target Ladybird Beetles

The cotton aphid, Aphis gossypii, is a worldwide agricultural pest in crop, fruit and vegetable.The damages of aphids is related to is wing ploymorphism. But studies on wing polymorphism in A. gossypii is largely unknown, especially on melcular level. Currently, aphids are becoming an increasingly important model system to understand wing polymorphism in insect.Digital gene expression(DGE) and Suppression subtractive hybridization(SSH) were used to study female wing polyphenism in A. gossypii. Differental expressed transcripts were investigated in female wing polyphenism cotton aphids. Then data analysis was profermanced. The object is to gain the melcular basis of biochemical composition differences between winged and wingless morphs.And summarize the features of two different technical methods to help everyone chose a better one for a particular case.1. We identified1,663differentially expressed transcripts, among which58were highly expressed in the winged A. gossypii, whereas1,605expressed significantly higher in the wingless morphs in DGE.2. In addition,20differentially expressed transcripts detected by DGE were validated by the quantitative real-time PCR.3. The expressed sequence tag(EST) seuqence of A. gossypii show a better performance than genome sequence of Acyrthosiphon pisum as reference sequences in DGE analysis.4. Forward and reverse SSH cDNA libraries were constructed,534and200EST were generated, respectively.97and55unigenes were obtained in two libraries.5. DGE required a bioinformation background and SSH ask for a skilled experimental skills. The former usually gives more results, while the latter didn’t a special machine.We study on dsRNA targeting V-ATPase subunit A in western corn rootworm Diabrotica virgifera virgifera effect on non-target insect, two specises of ladybird, Hippodamia convergens and Harmonia axyridis. The results show that the expression level of V-ATPase subunit A and survival rate are significant lower when4μg/μl Dvv dsRNA and He dsRNA are feeding on H. convergens. There is no significant changes on development time, pupa weight and adult weight. There is also no significant changes when0.5μg/μl dsRNA supplied for H. convergens and4μg/μl dsRNA supplied for H. axyridis.