锐劲特对南亚热带稻区水稻虫害与天敌影响的评价

Toxicity and Hazard Assessment of Pronil to Pest and Their Natural Enemies of Rice(Oryza sativa L.) in South Subtropical Zone

通过大田试验研究了无公害农药锐劲特悬浮剂在南亚热带稻区防治水稻多种害虫的效果及其对稻田害虫天敌的影响,试验设5个处理:锐劲特5%SC30mL、锐劲特5%SC50mL、锐劲特80%WG3g、锐劲特5%SC20mL+敌杀死2.5%15mL、锐劲特5%SC20mL+三唑磷20%EC100mL、三唑磷20%EC150mL+杀虫双18%水剂300M和空白对照(清水,CK)。结果表明:30￣50mL.0.067hm-25%锐劲特防治稻纵卷叶螟药效明显而持久,防效达100%,但兼治稻飞虱疗效有待进一步改善,而锐劲特+蚍虫啉类药喷施水稻防治效果最佳,几乎可防治所有水稻害虫,水稻总产量比不施农药虫害严重的对照区提高81.77%。但所有农药包括锐劲特对天敌都有一定的杀伤力,锐劲特对隐翅虫杀伤作用比较明显,对蛙类、蜘蛛也有一定的伤害作用,说明施用无公害农药对农田生态系统也有一定的风险。

The objective of this study was to evaluate toxicity of pronil and to determine the potential hazard posed by the insecticide against the pest and harmful to their natural enemies in rice paddy of South subtropical region.Field experiment were carried out with five treatments of spraying pronil at dosages of 5% SC 30 mL,and 5% SC 50 mL,and 80% WG 3 g,and 5% SC 20 mL +(Decamethrin K-othrin-Decis Deltamethrin) 20% EC 100 mL,triazophos 20% EC 150 mL + Bisultap 18% 300 mL and water(CK),respectively.The samples from the each treatments were replicated with three times.The result showsed that: 5% pronil of 30~50 mL·0.067 hm-2 had the best result in controlling Cnaphalocrocis medinalis(Guence) and other rice pests for a long time.In addition,total output of rice increased by 81.77% in the treated area comparison with the control plot.However,.all other treatment plots by insecticides had toxicity to predatory natural enemies in the rice paddy.Species richness and community diversity of predatory natural enemies took from dissimilarly by using different insecticides,especially those were sprayed with triazophos + bisultap declined more obviously than fipronil.The individual number controlled with fipronil was more than the other insecticides.This paper proved that fipronil has better function in controlling pests.In spite of fipronil was safer than other insecticides,but it still has some side-effects to predatory natural enemies in controlling pests in rice paddy field.