棉铃虫兼性迁飞的初步研究

PRELIMINARY STUDIES ON FACULTATIVE MIGRATION OF COTTON BOLLWORM IN CHINA

本文用吊飞装置测定了棉铃虫成虫不同日龄的飞行能力，测得３日龄雌蛾平均飞行速度为０．９２ｍ／ｓ，平均飞行时间为９．７２±３．６２ｈ，并与其他迁飞性和非迁飞性昆虫作了比较。在实验室条件下研究了温度和食料对生殖前期及繁殖的影响，证实此虫适于迁飞的生理时期较短，最多仅１～２个夜晚。用雌蛾卵巢解剖方法比较了江苏丰县和辽宁朝阳两地二代和三代的虫源性质，分析了两地的发蛾特征。证实朝阳１９９５～１９９６年的二代和部分三代成虫均从外地迁入，但与粘虫不同，迁入种群无突增现象，蛾群稀疏而持续不断。而江苏丰县则在１９９４～１９９６年均无明显迁入现象，以本地虫源为主。讨论了中国棉铃虫的迁飞势能和兼性迁飞的特性。

The flight capacity of moths was studied and compared by using the flightmill.The average flight speed of the 3rd day female moths was tested as 0.92 m/s, the average flight time was 9.72±362 h.The effects of temperature and food on prereprodutive period,fecundity and lifespan were studied in laboratory.The results showed that the prereproductive period was only 2.13±0.67 d under 28 ℃,it seems that the physiological fitting period for migration was quite short,only 1～2 night at most .The population sources of Fengxian,Jiangsu province and Chaoyang city,Liaoning province were studied by analysis of the dissecting of females ovary and the patterns of moth occurrence sequentially .It is indicated that during 1995～1996 moths of the 2nd and 3rd generations in Chaoyang all or partly immigrated from southern areas ,but the immigrating population were different from the tipical migratery spicies such as armyworm,appeared as no sudden occurrence but scatted and successive. However, in Fengxian there were no migration during 1994～1996. The facultative migration and potential for migration of this spices were discussed.