温度和寄主虫龄对单白绵绒茧蜂生长发育的影响

INFLUENCE OF TEMPERATURE AND HOST AGE ON THE DEVELOPMENT OF APANTELES SP.PARASITOID OF ECTROPIS OBLIQUA[LEP.:GEOMETRIDAE]

茶尺蠖幼虫期的重要寄生性天敌──单白绵绒茧蜂在１４和３４℃恒温下，供以寄主，无子蜂羽化。在１８～３０℃下，其幼期（卵──蛹）一般随温度上升而缩短，反之则延长；发育起点温度为９．９８±２．７８℃，有效积温２５０．００±４６．７７日度，由此推算在杭州年可发生ｌｌ～１３代。成虫寿命则随温度升高而下降，自然交温下趋势一致。寄主虫龄对该蜂的卵＋幼虫期无显著影响，而在寄主体外的预蛹＋蛹的历期则随寄主虫龄增大而缩短。

Laboratory studies were conducted on the effect of temperature and host instars on the development of Apanteles sp.[Hym.:Braconidae],an important parasitoid of tea geometrid,Ectropis obliqua Prout.When the parasitoid larvae were cultured under constant temperntures of 14℃ and 34℃ no adult emergence occurred.When the parasitoid was cultured under the temperatures of 18-30℃, the developmental periodof the immature stages(egg to pupa) shortened as the temperature increased:The initial developmental threshold temperature and effective accumulative temperature were determined as 9.98±2.78℃ and 250.00±46.77 day-degrecs.It is thus postulated that the parasitoid may have ll-13 generations a year in Hangzhou,It was also found that the adult longevity declinced as the temperature increased.The same trend was observed when the parasitoid was reared under the natural fluctuating temperatures.Host age was found to have no significant effect on the egg nor larval developmental periods of the parasitoid;but the pupal and pre-pupal developmental periods shortened as the host instar increased.