Studies On The Resistance Of Liriomyza Sativae To Insecticdes And Its Resistance Mechanisms

Liriomyza sativae Blanchard (Diptera:Agromyzidae), is an important insect pests damaged on vegetable crops, with high reproductive ability and rapid evolution of insecticides resistance, lead to big problem to pest control in the field. In order to make sure what’s the potential mechanisms for the abamectin resistance in L. sativae, we studied one resistant strain, which was selected with abamectin about one year with more than22genberations under lab condition, and we got two resistant strains compared to susceptible strain. After analysis the genetic regular of resistance by virulence detection, hybridization, and study the biochemical mechanism based on enzyme activity detection of pupa and used synergist, our research results indicates that:We established one resistant strain (41.8-fold) to abamectin compared with the susceptible strain in the laboratory.We performed the genetic analysis after the hybridization of resistant line with susceptible line, the results indicates that resistant gene located on the autosomes with incomplete dominate inheritance and controlled by multi-genes.We compared the different enzyme activity of susceptible and resistant line to reveal that the glutathione S-transferase and acetylcholinesterase is closely related to abamectin resistance. In addition, laboratory-selected strains of WFT were used to analyse the effects of the synerists, results indicates that DME and TPP hold the largest difference on synergistic effect between susceptible and resistant lines. This result further confirms that glutathione S-transferase and acetylcholinesterase play a very important role in the development of resistance to abamectin.We have tried to establish cyromazine resistance strain of L. sativae Blanchard under laboratory selection with cyromazine for about one year, but failed, However, high level cross-resistance to abamectin was found in this cyromazine-selected strain of L. sativae. The detail mechanisms for this are still unclear, the relative studies will keep going on under lab condition.