Effects Of The Insecticide On The Ultrastructure Of The Fight Muscle Of The Brown Planthopper Nilaparvata Lugens Stal (Hemiptera:Delphacidae) And Their Structural And Physiological Mechanisms

Brown planthopper, Nilaparvata lugens Stal (Homoptera:Delphacidae) is a kind of important rice pests in China, with long-distance migratory characteristics. N. lugens is also a kind of typical pesticide-induced resurgence pests. It has been demonstrated that triazophos can enhance the flight capacity of brown planthopper. Chlorantraniliprole is a new kind of pesticide,which inhibita the reproduction of brown planthopper. In order to understand the structure of flight muscle of pesticide induced enhancement of the flight ability of the brown planthopper,and explore the relevance of pesticide-induced resurgence and pesticide-induced enhancement of flight capacity, we analysed the ultrastructure of flight muscle of long-winged female brown planthopper Id,2d,3d, after emergence under the treatment of40ppm triazophos and50ppm Chlorantraniliprole using transmission electron microscopy. In addition we measured the titers of juvenile hormone III in long-winged female brown planthopper aging Id,2d,3d, after emergence under the treatment of40ppm triazophos. The results are as follows:1,Effects of the insecticide triazophos on the ultrastructure of the fight muscle of the brown planthopper (BPH)The results showed that the diameter of myofibrils at one and two days after adult female emergence(DAE) following treatment with40ppm triazophos was significantly greater than that of the control,increasing by31.4%and21.5%,respectively.In addition,the length of the sarcomeres at two and three DAE was significantly greater than that of the control,increasing by73.8%and50.8%,respectively.The percentage of mitochondrial volume in the muscle fibres at one and two DAE was146.2%and67.7%greater than that of the control,respectively. These findings show that the mechanisms of triazophos-induced enhancement of the fight capacity of BPH involved in changes in the ultrastructure of the fight muscle. 2,Effects of the insecticide chlorantraniliprole on the ultrastructure of the fight muscle of the brown planthopper (BPH)The results showed that there was no significant difference in the diameter of myofibrils, the length of the sarcomeres, the percentage of mitochondrial volume in the muscle fibres at one, two and three days after adult female emergence(DAE) following treatment with50ppm chlorantranilipro compared to the controll. These findings show that the insecticide that inhibited the reproduction of BPH has no effects on the ultrastructure of the fight muscle of the BPH. These results indicate that there is a positive relevance of pesticide-induced resurgence and pesticide-induced enhancement of flight capacity.3,Effects of the insecticide triazophos and indoxacarb on the titers of juvenile hormone Ⅲ in the BPHThe results showed that the titers of juvenile hormone Ⅲ(JH Ⅲ) at1and2DAE following treatment with40ppm triazophos was significantly increased compared to control,increasing by26.70%and19.82%,respectively. But there was no significant difference was found at3DAE. The titers of JH III at3DAE following treatment with40ppm triazophos significantly decreased compared to control,decreasing by22.26%. In addition, indoxacarb, which can inhibit the reproduction of BPH, significantly reduced the titers of JH Ⅲ in BPH. These findings show that the insecticide triazophos influenced the content of JH Ⅲ BPH, and the effects are involved in pesticide-induced resurgence and pesticide-induced enhancement of flight compacity.