Biology and predation efficiency of Menochilus sexmaculatus (Fab.)

Abstract

This study conducted the biology, morphological characteristics and predation efficiency of lady beetle Menochilus sexmaculatus. The mean pre-oviposition period of the beetle was observed 3.9 days, while the oviposition period was 21.5 days. Female beetles laid on an average 387.4 eggs and the hatching rate was recorded 94.8%. The average incubation period was found 3.1 days and the duration of the larval period 8.2 days. The pre-pupal and pupal periods were recorded 1.5 and 3.5 days, respectively. However, mean longevity of male and female beetles were 32.3 and 34.2 days, respectively. The length of the egg was 1.2 mm and the breadth was 0.6 mm. The 1%, 2" 3" and the 4" instar larvae were 1.6, 3.6, 5.1 and 5.4 mm in length, while their breadths were 0.7, 1.1, 1.3, and 1.4 mm, respectively. The average lengths of the male and female pupae were 4.7 and 5.7 mm, and breadths were 1.9 and 2.1 mm, respectively. Length and breadth of adult male beetles were 5.1 and 2.5 mm, whereas the female lady beetles were 5.5 and 2.0 mm, respectively. The data of the predation efficiency of the beetles reveal that the larvae of the 4" instar showed significantly the highest performances and the 1“ instar showed the lowest. Female beetles were more effective in aphid predation in comparison to male beetles. Therefore, the results show a significant role of predation efficiency of M. sexmaculatus on bean aphid.