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The life table study of the rice bug, Leptocorisa acuta (Thunb.) on rice (R) and non-rice (NR) system
were conducted in the laboratory condition. The average individual fecundity was recorded 100.999
and 59.019 eggs on R and NR system, respectively. The nymphs were observed to pass through six
instars with in the duration of 24 and 22 days respectively on R and NR host. The accumulated
survival of adult was 20±0.58 and 12.22±0.33% respectively on R and NR system. The demographic
parameters of L. acuta on R was significantly differed (F=10.931, P< 0.005) from the NR system
with higher intrinsic (rm) and finite (λ) rate of increase (0.020 and 1.020, respectively) through
shorter doubling time (DT) of 34.449 days. The total generation mortality (K) of L. acuta was
minimum on R system (2.7721) and maximum on NR system (3.1496), whereas the overall
generation survival (GS) was in reverse order of K values (0.2 and 0.122, respectively). These
differences in the demographic parameters are due to better nutritional quality in R system relative
to NR system. Thus, by knowing such variations and most vulnerable stages from life table, one can
make time based application of appropriate control measures against the pest population.
Keywords: Leptocorisa acuta, demographic parameters, nutritional quality, vulnerable stages.