عنوان مقاله [English]
نویسندگان [English]چکیده [English]
The functional response of a predator is the base of prey-predator dynamics. Functional response of Serangium montazerii FÃ¼rsch at different egg densities (50, 100, 150, 200 and 250) of Dialeurodes citri (Ashmead) was studied in an open-patch experiment, in a growth chamber (25 Â± 1Â°C, 65 Â± 5% RH and a photoperiod of 16: 8 L: D h) on âThompsonâ navel orange (Citrus sinensis cv. Thompson) apical leaves. A type II functional response was obtained using logistic regression. The searching efficiency (a') and handling times (Th) of the female adults using nonlinear least-square regression were estimated as 0.0421 Â± 0.00945 h-1 and 0.0896 Â± 0.0362 h, respectively. Mean times required for the female predator to settle in a patch were 121.4, 140, 116, 83 and 78 minutes at above-mentioned prey densities, respectively. It was inversely density dependent (R2 = 0.740). The proportion of female predators remaining in open patches at the end of the experiment was directly dependent on prey density (R2 = 0.9). It was concluded that the type of functional response obtained here was in agreement with studies on this predator in closed patches.