关键词: 稻茎毛眼水蝇, 自然种群, 历期, 存活率, 繁殖力

Abstract: The development period, survival rate and fecundity of natural population of Hydrellia sasakii 1-5 generations were studied in 1993 - 1995. The results show that the duration of first generation was the longest, the third and fourth generations were the shortest. The hatching rate of egg and the survival rate of larva were the smallest at first generation. It is higher at second to fifth generation. The survival rate of pupa of first generation was the lowest and hereafter increased generation by generation. The sex ratio of adults were 1: 1 around. The precede period of egg oviposition was 2 d or so at first generation, 1. 4 d at second generation and 1 d or so at third to fifth generation. There were no significant differences among the number of egg oviposition of female at second to fifth generation. It averages 24 granules or so per female. At first generation, it is less than 21. 9 granules per female. The longevity of adults of first generation was the longest and hereafter shortened generation by generation. The population trend index of fourth generation was the largest and that of first generation was the smallest. Ichneumonidae is a natural enemy of Larva. Tetrastichus hydrellia and Braconidae are natural enemies of pupa.

Key words: duration, fecundity, Hydrellia sasakii, natural populatloni survival rate