Molecular characterization, developmental biology, and life table of ladybird beetle, Micraspis discolor and its predatory potential against Aphis gossypii

Abstract

Micraspis discolor (F.) is a highly abundant species of ladybird that is used as a potential biocontrol agent against plant pests. We studied the biology, life table parameters, and molecular characterization of M. discolor. In addition, we studied its predatory potential against Aphis gossypii Glover. The net reproductive rate (R 0) based on the development stage and two-sex life table was 21.61 eggs/individual. The rate of consumption increased with progress in each stage of the development. Compared to the other larval stages of the predator, the fourth stadium consumed the highest number of A. gossypii nymphs (123.72). Both females (956.6) and males (1221.5) consumed more prey (nymphs) than the larvae. The net consumption rate of M. discolor was 694.04 nymphs of A. gossypii. The mitochondrial cytochrome oxidase subunit 1 (CO-I) gene was successfully sequenced from M. discolor. We used only the 514 bp length sequence for diversity analysis, with no character variable or insightful parsimony. Based on the results obtained, we conclude that M. discolor could be used as a biological control agent against A. gossypii.