Predation Rates of Coccinella septumpunctata Linnaeus and Chilocorus infernlais Mulsant on Aphids

The functional response of the Coccinella septumpunctata Linnaeus and Chilocorus infernalis Mulsant to increase the predatory potential of aphids and numerical response with fixed density of prey (aphids) and increasing densities of C. septumpuctata and C. infernalis were examined. The functional response curve having a curvilinear rise to plateau as prey densities increased from 1 to 64 and curve predicted by the Holling disk equation did not differ significantly from the observed functional response curve. The rate of successful search and the handling time predicted by disk equation were 0.0566 and 1.473 in case of C. septumpuctata and 0.0602 and 2.833 in case of C. infernalis, respectively. The numerical response having a linear rise to a plateau as aphid density fixed (20) with varying densities of C. septumpuctata and C. infernalis from 1to7. this response is consist with the view the Coccinellids as a group was involved under condition of food limitation and rate of attack was also decrease with interference of other Coccinellids.