真水狼蛛的生物学和田间种群动态研究

真水狼蛛在湖北武汉1a发生3个不完整的世代,以第2代历期最短,第3代(越冬代)历期最长。主要以亚成蛛越冬。雌、雄均可多次交配。真水狼蛛1生最多可产4个卵袋,平均2.8个,含卵量较大(平均90粒)。雌蛛有较强的护卵、护幼习性。卵的孵化率较高,平均孵化率为91.36％。真水狼蛛共蜕皮6次,有7个龄期。性比各个世代均为雌蛛多于雄蛛。真水狼蛛捕食叶蝉、飞虱等多种水稻害虫,捕食量与龄期、蜕皮和性别有关。真水狼蛛在6月5日左右开始由田埂向稻田内迁移,1a有2个发生高蜂,分析了影响真水狼蛛种群动态因素。

STUDIES ON BIOLOGY OF THE SPIDER, PIRAT A PIRATICUS AND ITS POPULATION DYNAMICS IN RICE FIELDS

The biology of Pirata piraticus, one of the major spiders in rice fields,was examined under laboratory conditions and fields. In the Wuhan area,the spider over - winters mainly as penultimate mstar. It has 2-3 generations each year,the duration of the 3 rd generation is the longest,that of 2 nd generation is the shortest. Both female and male mate several times without cannibalistic behavior. One female can lay 2-4 egg sacs and the average number per egg sac is 90. The mean hatching rate of eggs is about 91. 36%. After molting six times, spiderlings become mature. The sex ratios of female to male in all generations are bigger than 1 :1. The spider can prey on many kinds of rice pest insects. The spider begins to move into the rice field from the levee on 5 June,the population density have two peaks in one year.