Effect of two types of aphids on the predatory ability of Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae) in the laboratory.

Abstract

This study was conducted in Biological Control Studies and Researches Center in Faculty of Agriculture (Damascus) in 2016 (From the month of March to the month of May). The purpose of this study was to evaluate the Predation Efficiency of the variegated ladybug, Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae) on two aphid species; black bean aphid Aphis fabae Scop. and cabbage aphid Brevicoryne brassicae L. (Hemiptera: Aphididae), under controlled conditions in the laboratory (25±1 ºC, 65%±5 RH and 16:8 L:D). Third and fourth nymphal instar of the tested aphid species was used to compare the prey consumption rate of individuals resulted of these two kinds breeding. Individuals fed on A.faba displayed significantly the highest Predation Efficiency for larval stage (30.16 Nymph/ Larva/ day), also highest Predation Efficiency for adult (females) (56.80 Nymph/ females / day). The Predation Efficiency of females was significantly higher than males on all tested preys.