短时高温对普通大蓟马存活的影响及豇豆田防效初探

Effects of Short-Term High Temperature on Survival of Megalurothrips usitatus(Bagnall)and Control Effect of Cowpea Field

目前普通大蓟马的最主要防治措施仍然是化学防治,亟需开发绿色防控技术。本研究通过室内试验(不同温度及暴露时间处理)和田间试验(豇豆苗期和抽蔓期不同揭膜时间)初步探索短时高温对普通大蓟马存活率的影响及田间防治效果。室内试验结果表明,短时高温对普通大蓟马的存活率具有显著影响,且随着温度的升高和暴露时间的延长,影响愈发明显;42℃高温处理3 h,普通大蓟马成虫和若虫均全部死亡,而44℃处理1 h可使若虫全部死亡、处理0.5 h使成虫全部死亡。田间试验结果表明,豇豆苗期和抽蔓期在11:00—12:00揭膜,对普通大蓟马成虫的防效均可达到99%以上,处理后2 d内的防治效果仍能保持在70%及以上,但12:00以后揭膜偶发烧苗现象。

At present,chemical control remains the most effective means of managing Megalurothrips usitatus(Bagnall).Nonetheless,the urgency to develop environmentally friendly control techniques is paramount.In this study,the effect of short-term high temperature on the survival rate of M.usitatus and the effectiveness of field control were studied through an indoor experiment(different temperature and exposure time treatments)and a field experiment(different uncovering times at cowpea seedling and twigging stages).The results of the indoor experiment demonstrated that short-term high temperatures had a significant impact on the survival rate of M.usitatus.This impact became increasingly pronounced with increasing temperatures and prolonged exposure times.For instance,the high temperature treatment at 42℃for 3 hours resulted in the death of both adults and wipers of M.usitatus.Conversely,the treatment at 44℃for 1 hour resulted in the death of all wipers,while the treatment at 44℃for 0.5 hour resulted in the death of all adults.The results of the field experiment demonstrated that the cowpea seedling and twigging period revealed the film at 11:00-12:00,the control effect on adult M.usitatus reached a level exceeding 99%.Additionally,the control effect could be maintained at 70%and above for 2 days after the treatment.However,the uncovering of the film after 12:00 occasionally led to the phenomenon of seedling burning.