八种除草剂对多异瓢虫不同虫态的安全性评价

在新疆棉区，早春季节田埂杂草上滋养的天敌昆虫，是棉田内天敌的主要来源，也是棉田外天敌保育的重点。生产上，常喷施除草剂来防除田埂上的恶性杂草，从而除草剂可能会对非靶标天敌昆虫产生直接的不利影响。本文评价了新疆农田中常用的8种除草剂对多异瓢虫不同虫态存活的影响，发现8种除草剂喷施对多异瓢虫卵孵化率、蛹羽化率、成虫存活率均没有显著影响，精喹禾灵、苯磺隆、精噁唑禾草灵处理后3龄幼虫的存活率显著低于对照，而高效氟吡甲禾灵、精吡氟禾草灵、烯草酮、氯氟吡氧乙酸、乙氧氟草醚处理组的幼虫存活率与对照没有显著差异。利用高效氟吡甲禾灵、乙氧氟草醚药液处理多异瓢虫卵后，对卵、幼虫、蛹历期以及各虫态存活率、蛹重等均无明显影响，仅高效氟吡甲禾灵处理组幼虫化蛹率显著降低。利用高效氟吡甲禾灵、乙氧氟草醚处理3龄幼虫后，对其生长发育没有显著影响。本研究证实，新疆农田常用的8种除草剂对多异瓢虫比较安全，没有明显的毒杀作用与负面效应。

The Safety Evaluation of Eight Herbicides on Different Developmental Stages of Hippodamia variegate

In Xinjiang cotton-growing region, the natural enemies thriving on the weeds within non-crop habitats in early spring are the main sources of natural enemies immigrating into cotton fields, and are the key for natural enemy conservation outside cotton fields. In practice, herbicides are widely used to prevent malignant weeds on the ridges, which can potentially exert adverse effect on non-target natural enemies. In this study, we found no significant effects of eight herbicides on the egg hatchability, pupal emergence rate and adult survival rate of Hippodamia variegata (Goeze). However, the survival rate of the 3^rd instar larvae treated with Quizalofop-p-ethyl, Tribenuron-methyl, Fenoxaprop-p-ethyl was significantly lower than that of the control group while there were no significant differences in larval survival rates in the larvae treated with Haloxyfop-P-methyl, Floazifop-p-butyl, Clethodim, Fluroxypyr, and Oxyfluorfen in comparison with the control group. Eggs treated by Haloxyfop-P- methyl and Oxyfluorfen showed no significant differences in immature developmental duration, survival rates and pupal weight, with exception of significantly reduced pupation rate in Haloxyfop-P-methyl treatment. No significant effect was observed on the growth and development of 3^rd instar larvae treated with Haloxyfop-P-methyl and Oxyfluorfen. The study show that the herbicides commonly used in Xinjiang farmland are relatively safe for H. variegate, with no obvious toxic and negative effects.