【摘要】 研究了二斑叶螨实验种群的密度效应。实验结果表明二斑叶螨卵期不存在密度效应;幼、若螨期间存在密度效应,幼、若螨密度与其成活率明显相关,幼、若螨初始密度的增加导致死亡率增加,并且当代性比向偏雌方向发展,而子代性比向偏雄方向发展;不同成螨密度对成螨寿命和产卵量均有极显著差异。四季豆叶片上螨口密度大于2.5～3.5头/cm2时,扩散量明显增加。更多还原

【Abstract】 The effects of density-dependence on the experimental population of Tetranychus urticae Koch was studied. There was no density dependent effect in egg period. The density of larva and nymph had significant effect on the survival rate. With the rising of initial density of larva, the rate of death increased and the offsprings of present generation tended to have more female adults in sex ratio, but the offsprings of filial generation tended to have more male adults. The density changes of adults led to obvious differences in longevity and fecundity. If the density of adults surpassed 2.5～3.5 per square centimeter in kindney bean leave, the dispersal increased clearly.更多还原