Studies on population ecology of Thrips palmi Karny. X. Differences in population growth on various crops

Abstract

The differences in the population growth of Thrips palmi Karny On various fruit vegetable crops (cucumber, melon, pumpkin, balsam pear, eggplant, sweet pepper, tomato, kidney bean, okra and strawberry) and chrysanthemum were examined in rearing experiments. The survival rates of the larval and pupal stages fed on cucumber, kidney bean, eggplant and balsam pear were high, whereas the survival rates of those fed on okra and chrysanthemum were low. The larvae fed on tomato and strawberry were unable to pupate. Duration of the larval and pupal stages fed on chrysanthemum and okra was longer than the duration of those fed on other crops. The longevity of the adults fed on cucumber, pumpkin, eggplant and kidney bean was increased, whereas the longevity of those fed on chrysanthemum, tomato and strawberry was decreased. The fecundity of female adults fed on cucumber was maximum and the value was 60, while the fecundity of those fed on melon, eggplant and pumpkin amounted to 20. The differences in the generation time were not significant between crops, unlike the differences in the net reproductive rate. The intrinsic rate of natural increase of T. palmi fed on cucumber was maximum and the value was 0. 134, while that of T. palmi fed on melon, eggplant and pumpkin ranged from 0.08 to 0.11. © 1986, JAPANESE SOCIETY OF APPLIED ENTOMOLOGY AND ZOOLOGY. All rights reserved.