Fecundity and survival of pulse beetle (Callosobruchus chinensis L.) on green gram

The study aimed to investigate the fecundity and survival of the pulse beetle Callosobruchus chinensis Linnaeus on two varieties of green gram, CD 6-52 and CD 6-53. The experiment was conducted at the Post Graduate Laboratory in the Department of Agricultural Entomology, College of Agriculture, Latur, during the 2023-2024 period. When reared on the CD 6-52 and CD 6-53 varieties, the survival rates of the immature stages were recorded as 0.59 and 0.49 per individual, respectively, with a developmental time of 31 days for each. The net reproductive rate (R0) was found to be 26.40 and 16.83 females per generation for CD 6-52 and CD 6-53, respectively. The mean generation time (T) was 40.16 and 40.32 days for the two varieties, while the intrinsic rate of increase (rc) was 0.081 and 0.070 females per female per day, respectively, and the finite rate of increase (λ) was 1.20 and 1.17 females per female, respectively. On CD 6-52, the stable-age distribution of C. chinensis in the egg, larval-pupal, and adult stages was 62.09%, 36.90%, and 1.00%, respectively, whereas for CD 6-53, the distribution was 59.70%, 39.09%, and 1.20%, respectively.