针叶小爪螨的滞育研究

本文研究针叶小爪螨Oligonychus ununguis(Jacobi)滞育卯出现的规律，分析了光照、温度、寄主营养等环境因素与滞育的关系和滞育卵解除的条件。结果表明，针叶小爪螨以滞育卵在枝条上越冬，其产出盛期在8月上、中旬。光周期感应螨态为幼螨至第二若螨的连续两个螨态；其临界光照时间为13h/d。在相同条件下，低温(20℃)促进滞育。长日照下，螨口密度大，寄主营养恶化，亦能促进滞育的形成。滞育卵在0℃下放置1 20天，5℃-10℃下放置100天后解除滞育。

A STUDY ON THE DIAPAUSE OF OLICONYCHUS UNUNCUIS (JACOBI)

The present paper deals with egg diapause of Oligonychus ununguis(Jacobi). The effects of factors influencing diapause incidence including light, temperature and nutrition were investigated, and the condition terminating diapausewas recorded. O. ununguis overwinters with diapause eggs on host plant branches.Most eggs are laid in the beginning and middle of August. The threshold of photoperiod inducing diapause is at 13 hours light per day. The larva, protonymph are sensitive to photoperiodic changes, but adults and eggs are not. Lower temperature (20℃) promotes the incidence of diapause, when they are subject under the photoperiod of 10 or 13 hours per day. Similarly, diapause is also promoted by mite population density and unfavourable nutrition. The dlapause was terminated after treatment at 0℃ for 120 clays or at 5℃ or 10℃ for 100 days.