晚稻中后期二化螟为害特点及严重发生原因剖析

近年来 ,浙江省仙居县晚稻中后期二化螟ChilosuppressalisWalker为害日趋严重。分析原因 ,一是单季稻等桥梁田面积的不断扩大 ,使 8月底至 9月上旬田间出现了全年发生量最大的 2代主蛾峰 ,卵孵化盛期与连作晚稻抽穗期吻合 ;二是冬春气温升高 ,发生期提早 ,2代虫源寄主、水稻移栽期等的多样化 ,使 3,4代发生期拉长 ;三是因 3代主峰和 4代的螟害发生具有“隐性”的特点 ,其测报和防治工作被忽视 ;四是二化螟对常用药剂的抗药性提高。据此提出了相应的治理对策

Damages and occurrence analysis of Chilo suppressalis in late rice field

The damage of striped stem borer Chilo suppressalis Walker in late rice becomes more and more serious in Xianju County of Zhejiang Province.The more single season rice was planted as the bridge field area, in which annual biggest main moth summit in late August and early September was took place and resulted in whose maximum egg hatching stage coinstantaneous with the heading stage of late rice.In addition,the variation of the 2nd generation of the insects source and paddy planting stage,made the 3,4 generation occur stage became long, because of the high temperature in winter and spring seasons.The incorrect of forcasting,the ignorance of control and high resistance of striped stem borer to general insecticide also made its damage heaver.The management for striped stem borer was discussed in this paper.