异色瓢虫对烟蚜的捕食功能反应及密度干扰效应

异色瓢虫各龄幼虫及成虫对烟蚜的日捕食量差异较大，在相同的烟蚜密度条件下，异色瓢虫Ⅳ龄幼虫的捕食量最大，其次为成虫和Ⅲ龄幼虫。异色瓢虫各龄幼虫及成虫的功能反应均属HollingⅡ型。异色瓢虫自身密度对其捕食作用的干扰效应明显，对烟蚜的日捕食量异色瓢虫密度的增加而减少。

FUNCTIONAL RESPONSES AND DENSITY INTERFERENCE EFFECT IN HARMONIS AXYRIDIS PALLAS A PREDATOR TO MYZUS NICOTIANAE (BLACKMAN)

Great differences were found to exist between the larvae at different instars and the adult of Harmonis axyridis Pallas in their daily preying capacity for Myzus nicotianae (Blackman). With similar population density of M. nicotianae the 4 th instar larvae of H. axyridis had the greatest daily preying capacity, followed by the adults and 3 rd instar larvae. The functional responses of H. axyridis adults and larvae, irrespective of their instar stages, were of the Holling II type. The interference effect of the population density of the predator to its preying activity was significant, and as its density increased, the daily preying capacity decreased.