淡足侧沟茧蜂生物学特性研究

On the Bionomics of Microplitis pallidipes

为人工繁殖淡足侧沟茧蜂以控制甜菜夜蛾的发生为害,在室内恒温27℃条件下,以专用人工饲料饲喂甜菜夜蛾接种淡足侧沟茧蜂,研究了淡足侧沟茧蜂的生物学特性.结果表明:1)淡足侧沟茧蜂羽化多在白天,以8:00至16:00时最多,雄蜂早于雌蜂.出蜂时间6～7 d,以1～3 d最多,占90%以上.雌雄一生均可交配多次.未交配雌蜂其子代全为雄蜂.雌蜂产卵高蜂多在羽化交配后1～3 d,卵多产于幼虫腹部第5腹节与臀节之间;绝大多数寄主体内只产1粒卵.2)在一天中,侧沟茧蜂的寄生率以14:00至22:00时间段最高.雌蜂以第2天的寄生率最高.单雌一生平均寄生虫数可达101.6头.淡足侧沟茧蜂对甜菜夜蛾1～4龄幼虫的选择寄生比率分别为0.086 3,0.279 5,0.260 9,0.3733.

In order to breed Microplitis pallidipes to control Beet armyworm, Spodoptera exigua, at home constant temperature（27℃）, Beet armyworm, S. exigua were reared with the artificial special diet to breed the parasite wasp M. pallidipes, biology of M. pallidipes were studied The main results as follows： 1） The parasite emergence generally during day time, most of them were in 8：00 to 16：00, male wasps emerged earlier than that of females. The emergence time lasted for 6～7 days, and more than 90% wasps emerged during 1～3 days. Both male and female wasps copulated more than once over their living time. Offspring from unmated females developed to male wasps. The peak oviposition occurred in 1～3 days after mating, oviposition site in host larva was in abdomen between the 5^th and the last arthromere, female laid one egg in host body mostly. 2） The highest parasitism for M.pallidipes occurred in the day time of 14：00 to 22：00. The highest parasitism occurred in the second day after emerging during the period of oviposition. The average number of host larvae parasitized by one female wasp was 101.6. The proportion of host larvae selected for parasitism from 1^st～4^th instar were 0.086 3, 0.279 5, 0.260 9 and 0.373 3, respectively.