Functional responses and searching efficiency of Harpactor fuscipes on predation of Myzus persicae

Potential predacious ability, functional response and searching rate of H. fuscipes on Myzus persicae in lab were analyzed. Effects of intraspecific density and different spatial conditions on predation of H. fuscipes were studied. Result showed that the predacious functional response of H. fuscipes fitted to Holling II equation. The functional responses could be clearly described with such equation as Na=1.1153Nt/(1+0.0164Nt), and the maximum potential predacious ability of H. fuscipes on tobacco aphis was calculated as 194.89 individuals/day female. Predacious efficiency was reduced with increased mutual interference between individual predators. Predation ration(E) of predator decreased with the increase of H. fuscipes density. Space heterogeneity had great effects on predation, i.e. predation rate of predator decreased as environmental obstruction became stronger.