Abstract:
To investigate the predatory behavior of
Rhynocoris fuscipes against larvae of
Spodoptera litura, the predatory functional response, foraging efficiency and intraspecific interference response of
R. fuscipes at different stages on the 3rd instar larvae of
S. litura, along with the female adults of
R. fuscipes on the 2nd to 5th instar larvae of
S. litura were analyzed under indoor conditions, and the field control efficiencies of
R. fuscipes released at different predator-prey ratios on
S. litura were analyzed. The results showed that the predatory functional responses exhibited by male adults and the 3rd to 5th instar nymphs of
R. fuscipes on the 3rd instar larvae of
S. litura and female adults of
R. fuscipes on the 2nd and 3rd instar larvae of
S. litura were consistent with the Holling Ⅱ model, and female adults of
R. fuscipes on the 4th and 5th instar larvae of
S. litura were consistent with the new Holling Ⅲ functional response model. The maximum daily predation rates of R. fuscipe at different stages on the 3rd instar larvae of
S. litura in decreasing order were 15.38 (female adult), 14.49 (male adult), 11.24 (5th instar nymph), 8.77 (4th instar nymph) and 7.52 (3rd instar nymph). The maximum daily predation rates of
R. fuscipes adult females on the 2nd to 5th instar larvae of
S. litura were 27.78, 15.63, 9.19, and 6.00, respectively. The optimal foraging densities for the 4th and 5th instar larvae of
S. litura were 7.04 and 5.05 per dish, respectively. The foraging efficiency of adult female
R. fuscipes was higher than that of the other life stages, and the foraging efficiency gradually decreased with increasing population density of the 3rd instar larvae of
S. litura. With increasing density, the interference and competition between different life stages of
R. fuscipes were enhanced, leading to a gradual decrease in the rate of predation on
S. litura larvae. The control effects on
S. litura were 88.07%, 87.16%, 82.13% and 75.72% after 10 days of
R. fuscipes release at predator-prey ratios of 1∶5, 1∶10, 1∶15 and 1∶20 in the fields.
下载: