农药连用对烟蚜抗药性发展的影响

The effct of continually spraying pesticides on the development of resistance in Myzus nicotianae (Blackman)

40%氧化乐果和2.5%功夫连用对烟蚜抗性发展的影响研究表明,两种农药连续施用3次、6次和9次后,40%氧化乐果的抗 性指数增长了2.9倍、40.2倍和58.0倍,烟蚜的α-乙酸萘酯羧酸酯酶活力比值增加了1.3倍、9.6倍和11.1倍;2.5%功夫的抗性 指数增长了2.0倍、5.6倍和10.4倍,烟蚜的α-乙酸萘酯羧酸酯酶活力比值增加了1.0倍、9.7倍和12.8倍。随着农药施用次数的 增加,烟蚜α-乙酸萘酯羧酸酯酶的低抗个体频率减少,中抗及高抗个体频率增加。而β-乙酸萘酯羧酸酯酶、谷胱甘肽转移酶(GST) 及乙酰胆碱酯酶(AchE)的酶活力及其抗性个体频率的分布在抗性发展过程中的变化不大。因此,α-乙酸萘酯羧酸酯酶的酶活力及 其抗性个体频率的增加是40%氧化乐果和2.5%功夫连用后烟蚜抗药性快速发展的主要原因。

The effect of resistance development in %Myzus nicotianae% (Blackman) after continually spraying with 40% Omethoate and 2.5% Zeneca was investigated. Results indicated that after continually spraying at 3, 6 and 9 times, the %M. nicotianae% aphid's resistance index at 40% Omethoate was up 2.9, 40.2 and 58.0 times, and the ratio of α-NA activities increased 1.3, 9.6 and 11.1 times. The resistance index at 2.5% Zeneca was up 2.0, 5.6 and 10.4 times, and the ratio of α-NA activities increased 1.0, 9.7 and 12.8 times. With the increase of pesticides spraying times, the frequency of low resistant individual decreased for %M.nicotianae% aphid's α-NA, but the frequency of middle and high resistant individual increased. However, there was little change for enzyme activities and the frequency of resistant individual on β-NA, GST and AchE when the resistance developed rapidly. Therefore, it is the main reason that α-NA activities and the frequency of resistance individual for % M. nicotianae% aphid's resistance developed rapidly after 40% Omethoate and 2.5% Zeneca being continually sprayed.