烟青虫生物学特性观察

A Observation on the Bionomics of Heliothis Assulta (Guenee)in Honghe Prefecture of Yunnan

１９９６～１９９７年在云南省红河烟区弥勒县的烤烟大田设置尼龙纱网养虫室，自然条件下连续饲养烟青虫Ｈｅｌｉｏｔｈｉｓａｓｕｌｔａ（Ｇｕｅｎｅ），系统观察各虫态历期、幼虫龄期、取食量及体色变化，幼虫化蛹龄期及成虫羽化、产卵等．结果表明，烟青虫１年发生４～５代，各代均有５龄和６龄幼虫化蛹，５龄幼虫化蛹占６０％以上；１龄幼虫历期比２龄历期长，３龄以后龄期增长，末龄（５龄或６龄）幼虫龄期最长；５龄化蛹的幼虫平均历期比６龄化蛹的短；无论５龄或６龄化蛹，３龄以后食量剧增，５～６龄的取食量为１～４龄取食量的１倍以上；幼虫体色多变，１龄幼虫均为红褐色，２～６龄体色变化无规律可循，第２代以后体色有随世代增加而加深的趋向；成虫产卵量与补充营养关系密切，补充营养充足时，每雌可产卵６００～９００粒，一般情况产４００～５００粒，未交配雌虫也会产卵，但卵不能孵化．根据观察结果提出了防治中应注意的问题．

The tobacco budworm Heliothis assulta(Guenee) is one of the most important pests infesting tobacco in Honghe prefecture of Yunnan Province.It was reared on tobacco leaves under natural condition in 1996.The result shows that the insect has four or five generations each year,the pupae overwinter under ground.The larvae of the lst generation occur in 2nd ten days of May.The larvae of the 2nd generation.occur in 2nd ten days and last ten days of June.The larvae of the 3rd generation occur in last ten days of July.The larvae of the 4th generation occur in last ten days of August and lst ten days of September.The Larvae of the 5th generation occur in lst ten days of October.The larvae have many different color that vary with the instar and generation.Pupate in 5th instar or 6th instar.The rate of pupation in 5th instar is over 60%.The larval instar pupated in 5th instar is lengther than in 6th instar,but the larval stage pupated in 5th instar is shorter than in 6th instar.The larval capacity for eating i