青藏高原特有昆虫-草原毛虫生殖行为研究

Study on reproductive behaviors of Gynaephora alpherakii-an endemic species in Qinghai Tibet plateau

草原毛虫作为青藏高原区系中特有的昆虫种类,成为对草地危害最严重的有害昆虫之一.然而,关于草原毛虫生殖阶段的羽化、求偶和交配行为的研究报道尚少.基于此研究通过室内温度20±1℃,相对湿度75％～80％、光周期15L：10D条件下观察草原毛虫成虫的羽化、求偶和交配活动的差异.结果表明：草原毛虫羽化行为全天可见,雄虫羽化高峰期主要集中在10：00～12：00,而雌虫羽化高峰期集中在11：00～15：00和17：00～18：00两个时间段.羽化第3天发生求偶行为的虫数最多,第4d后开始逐渐下降,1,2和3日龄雌蛾求偶高峰期在16：30左右,而4,5和6日龄求偶高峰期在16：00左右.室内草原毛虫交配集中在9：30-19：30,交配高峰期出现在11：30和16：30左右,交配率高达55％和75％,且显著高于其他时间交配率（P＜0.05）.由此可见,草原毛虫雌雄成虫羽化、求偶和交配行为存在差异性,可能与青藏高原特殊的环境条件和昆虫适应性进化过程有关.

The grassland caterpillar （Gynaephora alpherakii）, endemic to the Qinghai-Tibetan Plateau, is a pest in Alpine meadow. However, studies on the behaviors of emergence, mating and calling female are seldomly reporeted. In this paper, these reproductive behaviors were studied by observations in the laboratory under the 22＋1℃, 75%-80% of relative humidity and 15L,10D photoperiod. The results showed that the emergence of G. alpherakii happened during whole day,especially froml0：00 AM to 12：00 AM for male, and from 11：00 PM to 15：00 PM and 17：00 PM to 18：00PM for female.The number of mating was the highest in third emergenceday. 3-day . however, the emergence number was decreased gradually in forth days. Calling time varied with the age of female,with older （ 4- to-7day- old） virgin females calling later and longer calling duration than younger （1-to-3-day-old） females. The mating was found in the daytime and the mating rate of females was the highest （ 55% and 75%） on 11：30 AM and 16：30PM, which is significant higher than in other time （P〈0.05）. Our study indicated that the adults of G. alpherakii were differenced in emergence, ealling and mating behaviors, which related to special environmental factors and the process of adaptive evolution for insects in Qinghai-Tibet plateau region.