三化螟抗药性与沙蚕毒素农药休用期关系的初步研究

通过苏中相关县市稻区三化螟蚁螟毒力的比较试验,结果表明沙蚕毒素系列农药(杀虫单)的休用期与三化螟蚁螟毒力呈负相关,休用期1年、2年、3年、3年以上的地区,三化螟蚁螟的LC50分别为57.22,27.17,15.48,4.70 mg/L,与广东始兴的相对敏感种群比较,杀虫单休用期3年抗性倍数为3.38~4.37倍,休用期3年以上地区的螟虫种群,对杀虫单已敏感程度基本与广东敏感种群接近。作者认为,三化螟蚁螟对杀虫单已产生抗性的地区,实施科学的休用期限,倡导两种或几种不同作用机制的杀虫剂轮换制,对遏制与延缓螟虫抗药性有积极意义。

Studying on the Relationship of the Resistance of Tryporza incertulas (Walker) and the Period Without Using Monosaltop

By compare the virulence of larvae of Tryporza incertulas (Walker) from the middil of Jiangsu, we can see negative correlation relationship between the period without using monosaltop and the virulence of larvae. LC50 of the larvae was 57.22, 27.17, 15.48, and 4.70 mg/L respectively in the counties where the period without using monosaltop was 1 year, 2 years, 3 years, and more than 3 years. Compared with the sensitive population of Tryporza incertulas (Walker) emerged lately in Guangdong province, the resistance would be 3.38~4.37 times if the period without using monosaltop for 3 years and the sensitive extent toward monosaltop would close to that of Guangdongs sensitive population if the period without using monosaltop was more than 3 years. It was significant to execute scientificly the period without using monosaltop in the areas where larvae have the resistance to monosaltop and to use 2 kinds of pesticides or more for control the resistance of Tryporza incertulas (Walker).