Studies on the biology of lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) at different seasons on wheat Ramalakshmi V.*, Satapathy C.R., Borkataki Shimantini1, Padhy Deepayan, Mounika T. Department of Entomology, M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakhemundi-761 211, Odisha, India 1Department of Entomology, Assam Agricultural University, Jorhat - 785 013, Assam, India *Corresponding authors' E-mail : ramalaxmiv06@gmail.com
Online published on 20 December, 2024. Abstract Stuides on the biology of R. dominica using a local wheat variety i.e. KW51 were conducted during the rainy season, 2022, (July - October, 2022) winter season, 2022 (November, 2022 - February, 2023), and summer season, 2023 (March -June, 2023). The results showed that the highest fecundity was observed during the rainy season counting 255-285 (Av. 274.13 ± 9.46) eggs per gravid female, followed by 113 - 178 (Av. 137.08 ± 21.07) eggs in the winter season, and 58 -69 (Av. 64.56 ± 3.49) eggs in the summer season. The egg period was observed to be an average of 5.00 ± 0.81 days in the rainy season, 6.50 ± 1.11 days in the winter, and the lowest duration i.e. 3.16 ± 0.73 days in summer. The grub and pupal period varied from 31 -36 (Av. 33.5 ± 1.71) days in the rainy season, 45 -54 (Av. 49.50 ± 3.19) days in the winter, and a minimum duration of 23 -29 (Av. 27.33 ± 0.94) days in summer. The development period from egg to adult male revealed that the adult males of the lesser grain borer took 33 - 37 (Av. 35.23 ± 1.43) days from egg laying to adult emergence in the rainy season. The sex ratio of female to male during rainy, winter, and summer seasons i.e. 1.38:1, 1.17:1, 0.93:1 respectively. Interestingly, the sex ratio in the lesser grain borer exhibited a reversal during summer, with a higher emergence of males compared to females. Top Keywords Biology, Fecundity, R. dominica, Sex ratio and oviposition period, Triticum aestivum. Top |