太湖稻区单季稻褐飞虱防控策略

太湖单季稻区褐飞虱的主峰迁入期是7月10-25日,20世纪90年代后是7月10-20日,迁入峰只有1个。若遇水稻分蘖中后期,则增殖1代就可进入主害代,若遇水稻分蘖前期,则需增殖2代才能进入主害代。处于分蘖后期至齐穗期的增殖代是主害代暴发的关键,盛夏高温对抑制褐飞虱的发生作用不大。随着农艺措施的改变,单季晚稻褐飞虱发生期由8月中下旬推迟到了9月25-30日,褐飞虱的发生已进入低迁入、高增长阶段,由此提出"治前补后"的防控策略和"狠治拔节至孕穗末期,补治穗期"的防治技术。

Management Strategy of Brown Planthopper in Single Cropping Season Rice in Taihu Lake Region

The immigrates dominantly of brown planthopper, Nilaparvata lugens Stal in single cropping season in Taihu Lake region is July 10-25, with only one migrating peak. When the immigration occurred during mid and late tillering stages of rice, the insect reached the most serious generation after reproduced only one generation. However, when the immigration occurred in early tillering stage, two generations were needed prior to outbreak. The reproduction from the immigration peak to brachypterous-aduh peak was u- nimportant for the formation of the most serious generation; however, the reproduction following the brachypterous-adult peak bad great contribution. As considering rice developmental stage, the reproduction from late tillering stage to the end of heading stage was crucial for the outbreak in later stages. The high temperature in summer could not suppress this insect evidently. The major occur- rence time was delayed from mid and late August to September 25-30 due to the changes in rice culturing practices, with the immi- gration being small while population increase being high. Based on these situations, we suggest that the insect in single-season rice should be controlled dominantly from jointing to the end of booting stages, and if necessary, additionally at heading stage.