Studies on temporal and spatial niches of cotton aphid,cotton bollworm and their predatory enemies

According to the study on the temporal niche，spatial niche and two-dimensional niche in time and space of the six predatory enemies of cotton aphid (Aphis gossypii Glover)and cotton bollworm (Heliothis armigera Huhner)，the temporal dynamics and role of these two pests played in the insect community were analyzed． The fo1owing up dynamics of predatory enemies and their impacts on these pests were evaluated．The results showed that insect pests could not be controlled if only by natural contro1． Therefore,IPM must be carried out．