【摘要】 自然天敌对稻飞虱发生数量的控制作用是很大的。特别是在水稻生长前期,天敌的作用使得不施药田的飞虱数量大多低于对照田。在水稻生长中后期,天敌的抑制作用相对下降。但是,如果自然天敌得到长期大面积的保护和利用,它们对稻飞虱的控制作用就会大大加强,在水稻中后期亦如此。自然天敌的长期大面积保护和利用,不仅可通过增加种库中天敌的种类和多样性,进而增强天敌群落重建和发展的能力,最终提高天敌群落对稻飞虱的控制作用,而且在水稻生长前期,对低密度下稻飞虱的捕食作用,能够推延稻飞虱的发生高峰期,减轻其发生程度。更多还原

【Abstract】 Based on the investigation data from Dashazhen Experimental Base, Sihui County,Guangdong Province, where the rice IPM was implemented on 4000 ha of paddy fields since 1973 mainly by giving rein to the control effect of natural enemies, it was found that the populations of rice insect pests in this township was lowest in Zhaoqing City,the damage of rice planthoppers in 98% of the paddy fields was kept under control and the numbers of other insect pests were also declined by natural enemies. Especially in early stages of rice, the actions of natural enemies in the rice fields without chemical control could keep the population of rice planthoppers lower than those with chemical control and delay their peak occurrence time.The long term preservation and utilization of natural enemies in large tracts of paddy fields can enhance not only the species number and diversity of natural enemies, but also promote the reconstruction of natural enemy community and its developmental ability, and finally strengthen the control effects of natural enemy community on rice planthoppers.更多还原