TY - JOUR AU - Maharjan, B. AU - Thapa, R. B. AU - Bajracharya, A. S.R. PY - 2018/12/03 Y2 - 2024/03/29 TI - Efficacy of Two Species of Coccinellid Predators Against Four Different Aphid Pest Species at Khumaltar, Nepal JF - Journal of the Institute of Agriculture and Animal Science JA - J. Inst. Agric. Anim. Sci. VL - 35 IS - 1 SE - Research Articles DO - 10.3126/jiaas.v35i1.22524 UR - https://www.nepjol.info/index.php/JIAAS/article/view/22524 SP - 127-134 AB - <p>An experiment was conducted in completely randomized design (CRD) to study the efficacy and biology of two coccinellid species with four aphid species at the mass-rearing laboratory of Entomology Division, Nepal Agricultural Research Council (NARC), Khumaltar from February to May 2016. Two coccinellid species, i.e. <em>Coccinella septumpunctata </em>Linn. and <em>Adonia variegate </em>(Goeze) were given four aphid species viz; <em>Myzus persicae </em>(Sulzer)<em>, Lipaphis erysimi </em>(Kaltenbach)<em>, Aphis craccivora </em>(Koch) and <em>Brevicorynae brassicae </em>Linn. separately to compare the efficacy of two beetle species as effective bio-control agent. Predatory activity of <em>C. septumpunctata </em>was the highest on <em>L. erysimi</em>(feeding 183 aphids) and the lowest on <em>A. craccivora </em>(feeding on 126 aphids), while, that of <em>A. variegate </em>(Goeze) was the highest on <em>L. erysimi </em>(feeding 155.4 aphids) and the lowest on <em>B. brassicae </em>(feeding 112 aphids) during their larval stages. Fourth instar individual larval weight of <em>C. septumpunctata </em>was recorded the highest (26.82 mg) when fed on <em>A. craccivora </em>and the lowest (13.9 mg) when fed on <em>B. brassicae</em>, while the 4th instar larval weight of <em>A. variegate </em>was only 12.82 mg and 11.34mg when fed on same aphid species. Pupal and adult weight was also recorded the highest for <em>C. septumpunctata </em>as compared to <em>A. variegata. </em>Similar result was obtained for weights of adult when larvae fed on <em>A. craccivora. </em>The weight of female was observed relatively higher than that of male from this study for both beetle species. There was a positive correlation between predation and weight gained by larvae with respect to all aphid species. From this study, it can be concluded that <em>C. septumpunctata </em>seems better promising species of predators of aphids, especially beneficial in biological control of aphid species.</p> ER -