Studies on predatory functional response and searching efficiency of Hippodamia variegate on Aphis sp.
liu ai-ping1; xu lin-bo1; wang jun-qing2 (1. grassland research institute of chinese academy of agricultural sciences; hohhot; inner mongolia autonomous region 010010; china; 2. college of life science and technology; inner mongolia normal university; hohhot; inner mongolia autonomous region 010022; china)