Studies on Species Composition and Prey Preference of Coccinellid Predators Associated with Major Field Crops of Jabalpur Region

Coccinellid beetles (Coleoptera: Coccinellidae) constitute one of the most important groups of natural enemies regulating populations of aphids and other soft-bodied insect pests in agro-ecosystems [2]. The present investigation was undertaken during two consecutive cropping seasons to document the species composition, seasonal abundance, crop association, and prey preference of coccinellid predators occurring on major field crops (wheat, mustard, chickpea, soybean, cotton, and pigeonpea) grown in the Jabalpur region of Madhya Pradesh, India. Roving surveys and fixed-plot sampling recorded a total of eight coccinellid species belonging to six genera, of which Coccinella septempunctata Linnaeus, Menochilus sexmaculatus Fabricius, and Coccinella transversalis Fabricius were the dominant and most frequently encountered species, together accounting for nearly two-thirds of the total population recorded. Peak coccinellid activity coincided with peak aphid infestation during the reproductive and pod/ear-formation stages of the respective host crops, generally between the second and fourth weeks of February on rabi crops and during September on kharif crops. Laboratory-based no-choice and multiple-choice feeding assays revealed marked inter- and intra-specific variation in prey preference, with Lipaphis erysimi and Aphis craccivora being preferred over Aphis gossypii by most predator species, although Menochilus sexmaculatus and Coccinella transversalis showed a distinct preference for Aphis gossypii on cotton. Fourth-instar grubs of Coccinella septempunctata exhibited the highest voracity, consuming a mean of 58.4 aphids per day. The findings underscore the ecological importance of conserving indigenous coccinellid diversity as a component of integrated pest management (IPM) programmes in the Jabalpur agro-climatic zone and provide baseline data for selecting efficient predator-prey combinations for augmentative biological control.