Study Of The DsRNA Absorbed Path On The Bemisia Tabaci Mediterranean RNAi Process

Whitefly (Bemisia tabaci) has become a worldwide agricultural pest, not noly canfeed on plant phloem sap,but also can spread plant viruses, brought huge losses for manycrops, vegetables, flowers, etc. B. tabaci has brought incalculable economic losses sinceit invaded into China in1990s and rapidly expanding in some areas. B. tabacimediterranean(MED) is Homoptera, Aleyrodidae, Bemisia. It has many biotypesbut MEAM1(B biotype) and MED (Q biotype)was the wide distribution and seriousharm biotypes in our country. In recent years,it was reported that MEAM1biotype wasreplaced by MED biotype in some areas both of them occured. Because of the Q biotype haswide host range, strong adaptability, serious harm andspreaded plant viruses. Soresearch of the effective control measures of B. tabaci is no time to delay, especiallyto use modern molecuLar biology combining with RNA interference technology andnew control methods of using RNA interference to silence genes. In this paperresearched the key protein gene of dsRNA absorption path using feeding dsRNA,the mainresults are as follows:1. Using PCR technology, cloned the gene full length of sid-1and Vacuolar H+ATPase through gene sequencing. Sid-1gene full length is2236bp, the open readingframe encoded636amino acids; Vacuolar H+ATPase gene full length is2989bp, theopen reading frame size is2516bp, and encoded838amino acids.2. Analyzed the gene homologous sequences with other organisms sid-1andVacuolar H+ATPase and constructed phylogenetic trees. The results showed that thesid-1gene similarity of B. tabaci and soybean aphid is81%, it indicated a highdegree of similarity. Vacuolar H+ATPase gene sequence similarity of B. tabaci andAcyrthosiphon pisum is90%, its closely homology with the relationship betwee them.3. Cloned gene template substrate of containing the T7promoter sequence of sid-1andVacuolar H+ATPase, synthesized double-stranded RNA sid-1gene and double-strandedRNA Vacuolar H+ATPase gene.4. Detected the gene silencing effect of the feeding dsRNA sid-1gene, Vacuolar H+ATPase gene and VgR by using fluorescence quantitative.The resuts indicated feedingdsRNA genes all have a conspicuous effect. Verified the dsRNA absorption path of the sid-1transmembrane channel proteins mediated. The results showed that the dsRNA absorption channelwas affected after sid-1gene is silenced, double-stranded VgR gene has not silencing effect, itcan be speculated that sid-1gene is a key gene of transmembrane channel proteins, the absorptionof the transmembrane channel proteins of dsRNA was affected after silencing sid-1gene.