二斑叶螨多重抗性品系的选育及其解毒酶活力分析

Selection of multiple-resistant strain and detoxification enzyme activities of Tetranychus urticae (Acari:Tetranychidae)

【目的】明确二斑叶螨对杀虫杀螨剂的多重抗性机制,为延缓二斑叶螨抗性发展及其抗性治理提供依据。【方法】以螺螨酯、甲氰菊酯和阿维菌素为靶标,通过室内抗性汰选获得二斑叶螨多重抗性品系(Mp-R),采用生化分析方法研究了Mp-R和敏感品系(SS)羧酸酯酶(CarEs)、谷胱甘肽S-转移酶(GSTs)和多功能氧化酶(MFOs)的活性差异,并估计了其抗性遗传力及相对适合度。【结果】经过连续50代室内抗性选育,二斑叶螨对阿维菌素、甲氰菊酯和螺螨酯的抗性倍数分别为603.03,167.65和51.77倍,其抗性发展趋势分别呈"慢-快-慢","慢-快"及缓慢上升趋势;与敏感品系相比,3大解毒酶活力在二斑叶螨各发育阶段均未见大幅度上升,仅Mp-R品系卵中MFOs比活力上升幅度最大,为SS品系的1.8倍;二斑叶螨对螺螨酯、甲氰菊酯和阿维菌素的抗性遗传力分别为0.020 3,0.038 7和0.064 2;Mp-R品系相对适合度为0.381 8(Rf<1),存在一定程度的生殖不利性。【结论】阿维菌素的抗性遗传力最大,具有较高的抗性风险;甲氰菊酯次之;螺螨酯的抗性遗传力最小,抗性风险较低;阿维菌素、甲氰菊脂和螺螨酯混用有利于二斑叶螨抗性治理。

[Objective] This paper researched multiple-resistant mechanism to offer theoretical basis to delay resistance development and resistance management of Tetranychus urticae. [ Method~ The multip resistant strain （Mp-R） was selected in indoor conditions, and its heritability and relative fitness were est e mated. The activity differences of CarEs, GSTs, and MFOs in Mp-R strain and SS strain were also tested u- sing biochemical analysis. [Result] The resistant ratios of Tetranychus urticae to abamectin,fenpropathrin and spirodiclofen were 603. 03 times, 167. 65 times and 51. 77 times, and the resistance developmental trends were ＂slow-fast-slow＂, ＂slow-fast＂ and ＂slowly rising＂. Compared with SS strain, 3 detoxification enzyme activities of Mp-R strain did not appear sharp rise in different developmental stages. Heritability of Mp-R strain to spirodiclofen,fenpropathrin and abamectin was 0. 020 3,0. 038 7 and 0. 064 2. Relative fit-ness of Mp-R strain was 0. 381 8, indicating that there was reproduction disadvantage in Mp-R strain. [Conclusion] The heritability was in a decreasing order of abamectin 〉 fenpropathrin 〉 spirodiclofen,and the resistant risk was in the same order. Mixture of abamectin,spirodiclofen and fenpropathrin was benefi- cial resistance control of Tetranychus urticae.