Spinosad对烟草甲生物活性的影响

Effects of Spinosad on Bioactivity of Tobacco Beetle

用含不同剂量Spinosad的烟叶和面粉为食料,研究其对不同形态的烟草甲及幼虫解毒酶的影响;同时配制不同浓度的Spinosad溶液点滴处理烟草甲幼虫。结果表明:Spinosad对烟草甲5龄幼虫的触杀作用和胃杀作用均较弱,但在5、10 mg/kg两种用量下,能完全抑制烟草甲卵的有效孵化和烟草甲成虫的繁殖,在处理后3～18个月内,Spinosad对烟草甲的防效分别为87.11%～99.11%和96.89%～100%;同时,Spinosad对烟草甲幼虫体内的羧酸酯酶(CarE)、谷胱甘肽转移酶(GSTs)和O-脱甲基酶活性均有明显的诱导作用,并对羧酸酯酶的动力学常数Vmax和Km也有一定影响。

The effects of Spinosad on tobacco beetles at different life stages and the detoxifying enzymes in larvae were studied by feeding tobacco beetles with tobacco leaves and flours containing different doses of Spinosad, and the larvae of tobacco beetles were treated with Spinosad solution of different concentrations. The results indicated that the contact and stomach toxicities of Spinosad to 5-instar larvae were weak, however at the concentrations of 5 and 10 mg/kg, Spinosad could completely inhibit the hatching of tobacco beetle egg and reproduction of adult tobacco beetle. The control effects of Spinosad at the concentrations of 5 and 10 mg/ kg on tobacco beetles were 87.11% to 99.11% and 96.89% to 100% in 3 to 18 months after treatment,respectively. Moreover, Spinosad had obvious induction to the activity of carboxylesterase（CarE）, glutathi- one-s-transferase （GSTs） and O-demethylase in tobacco beetle larvae, and also had certain effects on the kinetics constants, Vmax and Km, of carboxylesterase.