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The cowpea weevil, Callosobruchus chinensis Linn. is reported to be the most damaging pest of
stored legume seeds in the tropics and subtropics. In this study, biology and life table parameters of
the pest were investigated on green gram under laboratory condition at temperature of 25±3°C and
78±5% relative humidity. The experiments began from eggs and continued to the end of adult
longevity. The result showed that mean length of generation (T) were 44.87 days in first generation
and 42.68 days in second generation net reproductive rates (R0) were 11.64 females per female in
first generation and 13.74 females per female in second generation. The approximate rate of
increase (r approx) was recorded slightly lower than the actual rate of natural increase (r accurate) and
those were 0.547 females per female per day and 0.061 females per female per day respectively in
first generation while in second generation those were similar i.e. 1.056 females per female per day
and 0.061 females per female per day respectively. Finite rate of increase was 1.056 females per
female per day in first generation and 1.063 females per female per day in second generation.
Potential fecundity in first generation 27.50 females per female, and in second generation 28.50
females per female. Doubling time (DT) and weekly rate of increase (WRI) was 12.66 days and 1.46
females per female respectively in first generation and decreased to 11.28 days in second generation
followed by the increasement of weekly rate of increase to 1.53 females per female in second
generation.
Key words: Callosobruchus , Green gram , Age specific life table, Female fecundity table, Doubling time.