Harmonia sedecimnotata (F.): Predatory potential, biology, life table, molecular characterization, and field evaluation against Aphis gossypii Glover

Abstract

The ladybird beetle, Harmonia sedecimnotata (F.) was studied in biology, life table, consumption rates, molecular characterization, and feld evaluation. The net reproductive rate (R0), based on the agestage and two-sex life table, was 43.2 eggs/individual. The female adults lived longer (68.1 d) than the male adults (62.9 d). The rate of consumption increased with progress in each stage of development. Compared to the other larval stages of the predator, the fourth stadium consumed most quantities of Aphis gossypii Glover nymphs (Hemiptera: Aphididae) (200.4). Both female (2214.6) and male (1792.4) consumed more prey (nymphs) than larvae. The net rate of consumption was 1458.92 nymphs of melon aphids. There was no variation in the sequences of the two nucleotides out of 583bp, H sedecimnotata China (EU392410) and India (MG720024). Our investigations demonstrated that inoculative release of 30 or 40 or 50 adults per 100m2 attained high reduction of aphids (>90%). Thus, it may be recommended the release rate of 40 adults per 100m2 to suppress the eggplant aphid population. H. sedecimnotata is therefore one of the most promising biological control agents for cotton aphids that can be achieved for instant control through an inoculative release of adults.