Functional Response of the Predatory Ladybird Beetle, Coccinella undecimpunctata (Coleoptera: Coccinellidae) to Different Species of Aphids (Hemiptera: Aphididae)
Résumé
Coccinella undecimpunctata, a predatory ladybird beetle, plays a vital role in controlling aphid populations. Understanding its feeding efficiency at different life stages is essential for effective biological pest management. This study investigates the functional response of C. undecimpunctata to Aphis pomi and Aphis spiraecola under laboratory conditions, identifying the fourth instar larva as the most efficient predator. Functional response of different larval instars, adult males and females of the predacious coccinellid, Coccinella undecimpunctata, was evaluated under laboratory conditions in Division of Entomology Shalimar campus SKUAST Kashmir, to varying density of Aphis pomi and Aphis spiraecola. The life stages of Coccinella undecimpunctata exhibited a curvilinear Type II functional response. The fourth instar larva of Coccinella undecimpunctata consumed more aphids (19.2 ± 0.59 aphids per day each) due to its larger larval size and greater edacity as compared to female (17.70 ± 0.36 aphids per day by each) and adult male (16.09 ± 0.70 aphids per day by each) and third instar larvae (16.5 ± 0.52 aphids per day by each), when feeding on Aphis pomi subsequently. Similarly in case of Aphis spiraecola the fourth instar larval stage of Coccinella undecimpunctata consumed more aphids (17.9 ± 0.48 aphids per day by each) than female ( 16.6 ± 0.42 aphids per day by each), adult male (16.3 ± 0.53 aphids per day by each) and third instar larvae (16.0 ± 0.44 aphids per day by each). The search rate and handling time estimated for different stages of Coccinella undecimpunctata showed that the fourth instar had higher search rate, whereas the handling time showed the opposite trend as search rate. The results suggested that fourth instar larva of Coccinella undecimpunctata is the efficient predator for the biological control of Aphis pomi than Aphis spiraecola.