Effects of Food Combinations of Leguminous Seeds on Nymphal Development, Adult Longevity and Oviposition of Bean Bug, Riptortus clavatus Thunberg

摘要

This study was conducted to determine the effect of food combinations of leguminous seeds on the nymphal development and adult fecundity of Riptortus clavatus Thunberg. Nymphal duiation ranged from 20 to 28 days depending on food combinations with theshortest on the seed of soybean (Glycine max Linnaeus), soybean + kidney bean (Phaseolus vulgaris Linnaeus) and soybean + peanut (Archie hypogaea Linnaeus) and the longest on the seed of kidney bean. Instar duiation was longer with incieasing instar from 2.4 to 2.5 days in the 1st instar to 5.3 to 7.3 days in the 5th instar. Accordingly, instar duiation was significantly different on food combinations exception of 1st instar. Percent emergence varied fiom 3.5% on peanut to 65.0% on the seed of soybean+ peanut. Nymphal mortality was the highest in the 1st instai regardless of food combinations. Adult longevity was in range of 5.5 days to 11.2 days which was the shortest on the seed of kidney bean + peanut and the longest on soybean + peanut and was about 8.0 days on the other food combinations. Total numbei of eggs laid by female was most on soybean + peanut and was least on kidney bean+peanut. Accordingly, it can be recommended that food combination of the seed of soybean + peanut was the best and then was soybean only while other food comninations of leguminous seeds was hard to use for mass rearing of R. clavatus.