The Function Of Bactrocera Dorslis Spermatogenesis Related Genes

Bactrocera dorsalis is one of the most economically important fruit flies around the world. Because it is polyphagous and has strong reproductive capacity, it is causing a large amount of loss in fruits and vegetables industry every year. Nowadays, Bactrocera dorsalis occurs seriously as well as quickly spreading year after year. The original control measures such as chemical control can not work effectively against this pest. In this case, the environmental-friendly measures for the control of B. dorsalis is urgently needed to develop. Our research focus on the study in relation to the process of spermatogenesis in males of B. dorsalis. We use RNAi technology to silent spermatogenesis related genes and investigate the effects on the fecundity of B. dorsalis, which will pave the way to explore novel methods against this pest in the long run.Based on the B. dorsalis transcriptome database, we selected four spermatogenesis related genes gld2, timeless(tim), rae1 and gudu as target genes, then using feeding and injection treatments to silent target genes respectively. Then we focus on the effect of reproduction after RNAi treatment. The main results are as follows:1. We have successfully cloned c DNA of gld2, tim, rae1 and gudu which c DNA sequences were 505 bp, 642 bp, 866 bp and 585 bp. They are all highest homology with Bactrocera cucurbitae,and the rate are 91%, 91%, 91%, 89%.2. After silent gld2, tim, rae1 and gudu by feeding dsRNA the fecundity reduce.Compared with the control group 25.2 the treatment group were reduced to 11, 17.9, 11.4, 12.3 as follow. Morever, the genes could lead to significant reduction in egg hatchability. Hatching rate was 83.3% in the control group, while the treatment group hatching rate fell 70.6%, 70.7%, 67.3%, 69.9%. The gudu m RNA level up-regulation to 430%. In contrast, the gld2, tim and rae1 m RNA level down-regulation to 55%, 39 %, 38%.3. After silent gld2, tim, rae1 and gudu by injected ds RNA, compared with the control group the mating ratio was significantly reduced. What’s more, the gld2、rae1、gudu genes could leaded the fecundity reduced to 8.1, 5.5, 6.3 while the control group was 12.8. In addition, after these four genes were silented the hatching ratio was significant decreased. Hatching rate of control group was 84.2%, while the treatment group dropped to 58.5%, 65.1%, 52.9% and 69.1%.the gld2 and rae1 m RNA level down-regulation to 57%, 52%. In the opposite, The tim, gudu m RNA level up-regulation to 890%, 230%.