摘要：
蠋蝽是一种优良的天敌昆虫,可以捕食40余种鳞翅目、鞘翅目、膜翅目害虫.目前蠋蝽的规模扩繁大都采用室内饲养方法,因而种群出现了不可避免的近交衰退现象.本研究立足于分析近交繁殖对蠋蝽种群的影响,测定近交繁殖状态下,蠋蝽种群的一系列生命特征,为蠋蝽的规模扩繁提供依据.在室内饲养条件下,连续饲养6代蠋蝽种群,比较近交第6代种群和杂交种群在卵孵化率、各虫态发育历期、重量和性比等方面的差异.近交繁殖第6代种群与杂交种群相比,卵孵化率具有极显著差异,近交种群卵孵化率(43.66％)比杂交种群(66.28％)低22.62％.孵化历期比杂交种群的延长1.7 d.在各龄期历期比较中发现,近交种群的1、2、4和5龄若虫发育历期比杂交种群分别缩短0.29、0.03、0.08和0.51 d,而3龄则延长0.20 d,近交种群若虫发育历期(25.64 d)比杂交种群(26.34 d)短0.70 d.杂交种群各个虫态重量均比近交种群略有增加.在性比方面,近交种群会表现出显著的偏雄性.综上,近交繁殖第6代与杂交繁殖相比,在孵化率与成虫获得率方面显著下降,而在发育历期与各虫态重量方面并无显著差异.因此,在蠋蝽的室内繁殖过程中,应隔一段时间,采集远源虫源进行种群复壮,避免虫源衰退.%Arma chinensis is an excellent predator that can prey on more than 40 species of lepidoptera, coleoptera and hymenoptera pests. At present, A. chinensis are mostly reared in insectary, which can result in inbreeding depression. A series of life characteristics of A. chinensis population in inbreeding condition were determined, which can support insectary rearing of the predator. A. chinensis populations were inbred or outbred continuously in the insectary, and the differences between the inbred and outbred populations in egg hatching rate, developmental duration of nymphal stages, body weight and sex ratio in the sixth generation were analyzed. Compared with those of the outbred population, egg hatching rate of the inbred population (43.66％) was 22.62％ lower, egg hatching duration was 1.7 days longer. Developmental duration of each instar and the nymphs of the inbred population was marginally different from that of the outbred population. No significant difference was observed in weight between the outbred and inbred A. chinensis. The inbred population was significantly male-biased in comparison with the outbred population. Overall, the inbred population was significantly inferior to the outbred population in egg hatching rate and adult acquisition rate, while there was no significant difference in developmental duration and body weight. Therefore, outbreeding A. chinensis should be supplemented into the insectary rearing A. chinensis population to avoid inbreeding depression.
