Biometrics of the lady bird beetle, Menochilus sexmaculatus (Fabr.) (Coleoptera: Coccinellidae) fed on three different aphid hosts: Aphis craccivora, Lipaphis erysimi, and Hyadaphis coriandri under laboratory conditions from Rajnandgaon, Chhattisgarh

Abstract

The present studies on the biometric parameters of the lady bird beetle, Menochilus sexmaculatus (Fabr.) fed on three different aphid hosts viz., cowpea aphid, Aphis craccivora, mustard aphid, Lipaphis erysimi (Kalt.) and coriander aphid, Hyadaphis coriandri (Das), were evaluated in the Biocontrol laboratory, College of Agriculture and Research Station, Surgi, Rajnandgaon, Chhattisgarh during 2024-25. Across all the three hosts tested, maximum mean biometric parameters viz., egg length and breadth of 1.50±0.11 mm and 0.40±0.02 mm, mean grub lengths of 1.40±0.23 mm (first instar) to 7.04±0.38 mm (fourth instar), mean pupal length of 3.98±0.28 mm and length and breadth of adult males and females averaging 4.43±0.45 mm × 3.93±0.18 mm and 5.30±0.14 mm × 4.37±0.11 mm, respectively were recorded in M. sexmaculatus fed on cow pea aphid, A. craccivora ; followed by biometric parameters of M. sexmaculatus fed on mustard aphid, Lipaphis erysimi having mean egg measurement of 1.01±0.12 mm × 0.36±0.05 mm, larger adult females (5.23±0.04 mm). Lowest parameters on biometrics of M. sexmaculatus were observed on being fed on H. coriandri, having mean length and width of eggs 1.04±0.14 mm × 0.38±0.03 mm, size of the adult females (5.25±0.03 mm × 4.33±0.12 mm) here also exceeded than males (4.58±0.43 mm × 3.96±0.20 mm). These results highlight host-specific variation in growth with all three aphids supporting complete development but differing in biometric traits.