丁氟螨酯对二斑叶螨生长发育的影响

【目的】丁氟螨酯是一种新型酰基乙腈类非内吸性杀螨剂,对害螨的各个螨态都有很高活性,具有较高的应用价值。本文评价了丁氟螨酯对二斑叶螨生长发育的影响,以期为合理用药和二斑叶螨的综合防治提供理论依据。【方法】采用浸叶法测定丁氟螨酯对二斑叶螨成螨与卵的致死中浓度、雌成螨产卵量、各螨态存活率以及各发育历期的影响。【结果】经丁氟螨酯处理后,二斑叶螨日均产卵量和总产卵量下降,各螨态发育历期延长;LC₇₀、LC₅₀、LC₃₀剂量处理二斑叶螨雌成螨后,每雌日均产卵量为(2.09±0.17)、(3.02±0.22)、(3.39±0.13)粒,每雌总产卵量为(29.29±2.31)、(42.32±3.01)、(47.41±1.77)粒,与空白对照差异显著(P<0.05,df=3);不同剂量处理二斑叶螨卵后,各螨态发育历期的延长程度不同,但成功孵化的卵能完成发育历期,LC 70剂量延长卵历期至(4.45±0.07)d、前若螨历期至(2.75±0.04)d、后若螨历期至(2.61±0.05)d和总历期至(12.53±0.18)d,LC 50剂量延长前若螨历期至(2.52±0.08)d、后若螨历期至(2.67±0.09)d和总历期至(12.22±0.18)d,LC 30剂量延长前若螨历期至(2.45±0.06)d和总历期至(11.53±0.08)d,与空白对照差异显著(P<0.05,df=3)。【结论】丁氟螨酯能对二斑叶螨的生长发育产生明显影响,降低二斑叶螨的产卵能力,抑制卵孵化,延长发育历期,从而降低二斑叶螨种群的发育速率,对该螨的种群控制有积极意义。

Effects of the insecticide cyflumetofen on the growth and development of the spider mite, Tetranychus urticae Koch

Aim] Cyflumetofen is a novel acyl acetonitrile nonabsorbent acaricide, with high activity to pest mites at various mite states and high application value. The effect of cyflumetofen on the growth and development of Tetranychus urticae was investigated, so as to provide a theoretical basis for rational drug use and comprehensive control of T. urticae.Method] Leaf dipping method was used to determine the effects of cyflumetofen on the median lethal concentration on live adults and eggs, fecundity of female adult mites, survival rate and duration of each developmental stage.Result] After treatment with cyflumetofen, the average daily egg production as well as lifetime egg production of T. urticae decreased, and the developmental duration of each mite stage was prolonged. After treatment of female adult mites by LC₇₀ (4.86 mg·L^-1), LC₅₀ (2.37 mg·L^-1) and LC₃₀ (1.16 mg·L^-1), the average egg production was (2.09±0.17), (3.02±0.22) and (3.39±0.13) eggs·female^-1 one day, and the lifetime eggs production was (29.29±2.31), (42.32±3.01) and (47.41±1.77) eggs·female^-1, which was significantly less than the control (P<0.05, df=3). The LC₇₀ (20.95 mg·L^-1)dose extended the egg duration to (4.45±0.07) days, the protonymph duration to (2.75±0.04) d, the deutonymph duration to (2.61±0.05) days, and the total duration to (12.53±0.18) d, LC₅₀ (6.29 mg·L^-1) dose extension before protonymph duration to (2.52±0.08) d, deutonymph duration to (2.67±0.09) d and total duration to (12.22±0.18) d, LC₃₀ (1.89 mg·L^-1) dose extension before protonymph duration to (2.45±0.06) d and total duration by (11.53±0.08) d, it was significantly different from the blank control (P<0.05, df=3).Conclusion] Cyflumetofen had a significant effect on the growth and development of T. urticae, reducing its fecundity, delaying egg hatching and prolonging the development duration, thereby reducing the developmental rate of the population.