December 2023 | Volume 36 | Issue 4 | Page 369 Pakistan Journal of Agricultural Research Research Article Abstract | Research was conducted to evaluate the biological attributes and feeding eﬃciency of Menochilus sexmaculata fed on Lipaphis erysimi under laboratory conditions. e mean developmental time from egg till adult emergence was 41.60±0.70 days under laboratory conditions of 24±1c° with 55±5 percent relative humidity (R.H.). e incubation period was 4.00±0.25 days. e pre-oviposition, oviposition, and post- oviposition periods were observed at 8.6, 24.1 and 6.0 days, respectively. e total laid eggs/female were 288.4 eggs. e pre-pupae and pupae developmental time was 1.00±0.00 and 6.00±0.08 days, respectively. e overall mean male longevity was 33.40 days, while the mean female longevity was 38.70 days. In larval feeding eﬃciency, the maximum mean number of aphids (479.6) were consumed by larvae while the minimum mean number of aphids (36.8) were consumed by 1 st larva instar. Female beetle was recorded with a maximum mean number of aphids (2561) consumption as compared to male beetles (1921). Furthermore, the apparent mortality was highest at egg stage, making it the most vulnerable stage in the beetle’s life cycle, followed by 1 st instar larval stage, which also showed higher mortality. e maximum survival fraction was observed for pre-pual and fourth instar larvae, while the minimum was found for the egg stage. Mortality survival ratio (MSR) was found to be maximum at the egg stage and minimum at the 4 th instar and pre-pupal stages, while the Indispensable mortality (I.M.) was found to be maximum at the egg stage and minimum at 4 th instar and pre-pupal stages. Life expectancy (ex) was found to be maximum in the egg phase (4.67) and minimum in the pupal phase (1.5). e total K value for the whole generation was 0.33. Ashfaq Hussain 1 , Javed Khan 2 , Ammara Blouch 3 , Ahmad-Ur-Rahman Saljoqi 1 , Ashraf Khan 4,5 * and Zaheer Sikandar 6 1 Department of Plant Protection, University of Agriculture, Peshawar, Khyber Pakhtunkhwa, Pakistan; 2 Insect Pest Management Program, Institute of Plant and Environmental Protection, National Agricultural Research Centre, Islamabad, Pakistan; 3 Food Science Research Institute, National Agricultural Research Centre, Pakistan; 4 Institute of Plant and Environmental Protection, National Agricultural Research Centre, Islamabad, Pakistan; 5 Provincial Key Laboratory for Agricultural Pest Management of Mountainous Regions, Institute of Entomology, Guizhou University, Guiyang 550025, P.R. China; 6 Sugarcane Research Institute, Ayub Agricultural Research Institute, Faisalabad, Pakistan. Received | September 13, 2022; Accepted | November 23, 2023; Published | December 14, 2023 *Correspondence | Ashraf Khan, Institute of Plant and Environmental Protection, National Agricultural Research Centre, Islamabad, Pakistan; Email: ashrafkhan@parc.gov.pk Citation | Hussain, A., J. Khan, A. Blouch, A.U.R. Saljoqi, A. Khan and Z. Sikandar. 2023. Biology and feeding eﬃciency of zigzag beetle, Menochilus sexmaculatus (Fab.) (Coleoptera: Coccinellidae) fed on mustard Aphid, Lipaphis erysimi (kalt.) (Hemiptera: Aphididae) under controlled conditions. Pakistan Journal of Agricultural Research, 36(4): 369-376. DOI | https://dx.doi.org/10.17582/journal.pjar/2023/36.4.369.376 Keywords | Menochilus sexmaculatus, Lipaphis erysimi, Feeding eﬃciency, Survival fraction, Biological attributes Copyright: 2023 by the authors. Licensee ResearchersLinks Ltd, England, UK. is article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY ) license (https:// creativecommons.org/licenses/by/4.0/). Biology and Feeding Eﬃciency of Zigzag Beetle, Menochilus sexmaculatus (Fab.) (Coleoptera: Coccinellidae) Fed on Mustard Aphid, Lipaphis erysimi (kalt.) (Hemiptera: Aphididae) Under Controlled Conditions