阿维菌素对虚伪新小绥螨生长发育影响的初步研究

Effects of Abamectin on the Survival and Development of Neoseiulus fallacis (Garman)

室内评价了阿维菌素对虚伪新小绥螨的相对毒力。虚伪新小绥螨的卵和雌成螨经5个不同浓度的阿维菌素溶液处理后,观察生长发育情况。结果表明,高浓度的阿维菌素对捕食螨雌成螨的毒力显著高于低浓度。经过0.9 mg.L 1和0.6 mg.L 1的阿维菌素处理72 h后,虚伪新小绥螨的存活率下降50%,当阿维菌素浓度为0.3 mg.L 1时,处理144 h后成螨的存活率明显低于对照处理,但处理240 h后,虚伪新小绥螨的雌螨存活率与对照无显著差异。0.3 mg.L 1～0.9 mg.L 1的阿维菌素能降低虚伪新小绥螨的产卵量,随着浓度的升高,产卵量逐渐下降。但阿维菌素对虚伪新小绥螨卵的孵化率没有影响。浓度为0.3 mg.L 1～0.6mg.L 1的阿维菌素处理72 h内对虚伪新小绥螨幼螨的存活率影响不显著,但显著地影响幼螨的发育历期和若螨的存活率;在处理96 h后,阿维菌素处理的捕食螨若螨全部死亡。

The relative toxicity ofabamectin to the predator mites, Neoseiulusfallacis （Garman） was assessed in the laboratory. Eggs and female adults of the predator mites dipped into five different concentrations of abamectin were placed on bean （Phaselus vulgaris Linn） leaf disks treated by dipping into the corresponding concentrations of abamectin. The results showed that toxicity of abamectin to the adults of the predatory mites depended on the concentration of abamectin. Survival rate of N. fallacis female was reduced by 50% at 72 h after treatment with concentrations of 0.6 and 0.9 mg-L-1. At concentration of 0.3 mg.L-1, survival rate was significantly lower than CK at 144 h but recovered to the same level with CK at 240 h. Abamectin at the concentration between 0.3 and 0.9 mg＇L-~ significantly reduced reproduction of the predatory mite, but had no effect on the egg hatching. Moreover, abamectin at the concentrations of 0.3-0.6 mg-L-1 had no effect on larval survival rate within 72 h, but did affect the survival of nymph. After 96 h, all nymphal predators died when the concentrations were 0.3 to 0.9 mg.L-1. Further study is needed in the field to evaluate toxicity of abamectin to predatory mites and to develop abamectin-resistant N. fallacis for the control of the soider mites.