COMPARATIVE BIOLOGICAL STUDIES OF APHIS GOSSYPII GLOVER ON COTTON AND BRINJAL FOR MASS REARING UNDER LABORATORY CONDITION

Life table of Aphis gossypii

Abstract

The aptness of two hosts viz., cotton and brinjal for mass rearing of Aphis gossypii under laboratory conditions was investigated using the age-stage, two-sex life table method. The results showed that A. gossypii could complete its entire life cycle on both hosts. The total nymphal duration (7.93±0.33), reproductive period (6.95±0.60), adult longevity (8.11±0.68) and fecundity (24.66±2.34) were significantly higher on brinjal than on cotton. The differences in pre-reproductive and post-reproductive periods on both hosts were not statistically significant. The mean reproductive period was longer on brinjal (6.95±0.56 days) than that on cotton (5.06±0.47 days); consequently, the fecundity was also significantly high in brinjal (24.66±2.34 nymphs/female) compared to cotton (14.11±1.31 nymphs/female). The difference in an intrinsic rate of increase, infinite rate of increase and doubling time were non-significant. In contrast, the net reproductive rate, gross reproduction rate, and mean generation time on brinjal were significantly higher than on cotton. Life table parameters such as age-stage-specific survival rates, fecundity, life expectancy and reproductive value of A. gossypii were higher on brinjal compared to cotton. The results of this study indicate that brinjal is a better host than cotton for the mass rearing of A. gossypii.