秦治勇 李大庆 杨再学

摘 要：貴州省余庆县2020年稻纵卷叶螟大发生，其特点为成虫始见期比2019年晚、比历年早;主迁入期第3代成虫迁入峰次多、峰期长，迁入蛾量大，迁入主峰期推迟;第3代残存虫量大，第4代田间蛾蜂期长、补充迁入蛾量大;田间第3代、第4代幼虫连续大发生，幼虫量第4代大于第3代;危害高峰期比历年早，危害期长，第5代发生比历年同期平均轻。原因如下：在稻纵卷叶螟迁入期雨日多、雨量大，有利于成虫的迁入、交配、产卵和卵孵化;5月份气温回升快，水稻大田移栽提早，迁入成虫很快扩散于稻田产卵繁殖;第3代残存虫量和第4代补充迁入蛾量大，田间积累虫量大;6月上中旬及7月上中旬低龄幼虫盛发期雨日多，有利于稻纵卷叶螟的发生危害，不利于防治工作的开展等因素，造成第3代、第4代幼虫连续大发生。在稻纵卷叶螟大发生和特殊气候条件下，大面积的防控必须进行统防统治，才能事半功倍。

关键词：稻纵卷叶螟;发生特点;原因分析;应对措施;余庆县

中图分类号 S435.112+.1文献标识码 A文章编号 1007-7731（2021）05-0108-04

Abstract： In 2020， rice leaf roller occurred in yuqing county， Guizhou Province， which is characterized by the beginning of adult later than last year and earlier than previous years; During the main migration period， the third generation adults migrated with many peaks and a long peak period， and the number of migrating moths was large， and the main peak period was delayed; The third generation has a large number of residual insects， and the fourth generation has a long period of field moths and a large number of supplementary moths; The third and fourth generations of larvae occurred continuously in the field， and the number of larvae in the fourth generation was greater than that in the third generation The peak hazard period is earlier than the previous years， and the hazard period is longer. The fifth generation is lighter than the same period of the previous years on average. The reasons are as follows： （1） there are many rainy days and heavy rainfall during the migration period of rice leaf roller， which is beneficial to the migration， mating， spawning and egg hatching of adults; In May， the temperature rose rapidly， rice field transplanting was earlier， and the migrating adults quickly spread to the paddy fields to spawn and reproduce. The number of residual insects in the third generation and supplementary moths in the fourth generation is large， and the number of accumulated insects in the field is large; There are many rainy days in the peak period of young larvae in the first half of June and the first half of July， which is beneficial to the occurrence of Cnaphalocrocis medinalis， and is not conducive to the development of prevention and control work， resulting in the continuous occurrence of the third and fourth generation larvae. Under the severe occurrence of Cnaphalocrocis medinalis and special climatic conditions， to prevent and control a large area， large-scale prevention and control must be unified prevention and control so as to achieve twice the result with half the effort.

Key words： Cnaphalocrocis medinalis; Occurrence characteristics; Cause analysis; Response measures; Yuqing county

稻纵卷叶螟（Cnaphalocrocis medinalis Guenee）俗名水稻卷叶虫、包叶虫、裹叶虫，以幼虫缀丝纵卷水稻叶片成虫苞，幼虫匿居中其中取食叶肉，仅留表皮，形成白色条斑，致水稻千粒重降低，秕粒增加，造成减产[1]。稻纵卷叶螟在贵州省余庆县以第3代、第4代为主害代，每年都有不同程度的发生危害。2020年全县种植水稻面积0.83万hm2，稻纵卷叶螟第3代、第4代幼虫大发生，综合发生程度5级，总计发生面积1万hm2，是自1993年以来发生危害最重的一年，田间幼虫量第4代大于第3代。……