Growth and development of pulse beetle, Callosobruchus chinensis [l] on pulses

Abstract

Laboratory experiments were conducted to study the comparative growth and developmental biology of Callosobruchus chinensis in the laboratory at RVS Agricultural College, Thanjavur on different pulses. i.e., Five pulses [green gram (Vigna radiata), black gram (Vigna mungo), chickpea (Desi) (Cicer arietinum), cowpea (Vigna sinensis) and red gram (Cajanas cajan). Red gram received the highest number of eggs (71.20 ± 3.56 no. of eggs/ female) while minimum number of eggs laid on chick pea (27.80±2.33 no. of eggs/ female). Oviposition period and incubation period of eggs on different pulses shows non-significant. Hatchability per cent of egg were high (91.20 ± 1.32%) on black gram (91.20 ± 1.32%) and low on chickpea (79.20 ± 5.03%). The duration of larval - pupal was the highest on chick pea (27.80 ± 0.58 days) and the lowest on red gram (21.60 ± 0.40 days). Total life cycle of pulse beetle, Callosobruchus chinesis was less on red gram (25 .80 ± 0.20 days) and prolonged on chickpea (32.00 ± 0.89 days). Maximum adult longevity was observed on red gram (9.80 ± 0.58 days) least on black gram (7.60 ± 0.40 days) . No significant differences in sex ratio of pulse beetle among the different pulses were observed. The highest survival per cent was recorded in red gram (88.4 ± 5.37%) followed black gram (83.6 ± 5.52%) and low in chickpea (62.8 ± 5.26%). Green gram had minimum per cent of grain weight loss (24.61 ±6.27). The highest per cent grain weight loss was observed in red gram (32.37 ±4.59%).