Study On Mechanisms And Esterase Gene CDNA Cloning And Sequence Analysis From Tetranychus Cinnabarinus (Boisduval)

Tetranychus cinnabarinus is widely distributed in China, and often infests seriously, but difficult to control in cotton and many vegetables, the resistance level rise rapidly since 80 age, especially in cotton of our country. As a result of frequency of pesticide using, the status of resistance is very seriously. It is reported, T. cinnabarinus has come resistance into 25 kinds of insect and acaricide. Its management has been depending on insecticides for a long time, which result in its wide and high level resistance to insecticides. Many scholars carried out studies on resistant mechanism of mite at level of biochemistry, but few researches on the molecule resistance mechanism were reported, which set back efficient of mite management and further understanding of resistance evolution. Based on esterase electrophoresis and enzymes activities of the three strains of T. cinnabarinus, studies about cloning and analysis esterase of T. cinnabarinus were carried out and the results are as follows.1. Study on Esterase Isozyme of different resistance strain in T. cinnabarinusEsterase isozymes is that has the same biologic function, and is not has the same protein molecular constitute. The proportion of esterase isozymes band show its activity, the higher proportion the higher activity. The results showed that s strain of T. cinnabarinus had 4 bands, they are 0.42%,54.39%,25.09% and 20.10%; Rh strain of T. cinnabarinus had 3 bands, they are6.71%,63.46% and 29.83%; AbR strain had 5 bands they are5.35%,45.71%,29.44%,0.68%and 18.81%.2. Care and AChE activity of different resistance strain in T. cinnabarinusLately lots of studies carried out, that the main reason of insect resistance was potentiation of enzymes activity.We carried out, the protein content of Rh strain of T. cinnabarinus＞s strain's＞AbR strain's, and there had notability difference.The strains of T. cinnabarinus of enzymes activity are: AbR＞S＞, that indicate potentiation of CarE maybe cause T. cinnabarinus of resistance. In addition, AbR strain's protein content decrease, but CarE activity increase, that maybe CarE's quality has changed.In the study of AChE's activity, Rh strain of Z cinnabarinus of endurance maybe relate with potentiation of AChE's activity, we need more study.3. cDNA clone and sequence analysis of esterase gene inT. cinnabarinus.A pair of degenerate primers were designed by CODEHOP and were used to clone the esterase gene related with population of T. cinnabarinus using RT-PCR technique and sequenced. Esterase cDNA fragment is of 440bp encoding 130 amino acids,after the Blast comparison, the partial cDNAs were confirmed that they were esterase gene and they have high identity (89.7%) with Spodoptera litura. Magnitude of homologous character between T. cinnabarinus and other animal, Aedes aegypti,Boophilus microplus,Drosophila melanogaster and Musca domestica, they are 84%,83.2%,83%and 80.9%.