Abstract: Tytthus chinensis (Stål) is a key predator of rice planthopper, a major pest of rice in China. Biological control of rice planthopper could be much more effective and feasible by improving the techniques of artificial breeding of natural enemies. The purpose of this study was to test the effect of different survival substrates, including kidney bean, wet cotton ball and rice stem, on the growth, development and reproduction of T.chinensis. The results showed that different survival substrates had significant influence on the development, survival and reproduction of T. chinensis. The survival rate of T. chinensis was the highest in the rice stem treatment, followed by the kidney bean treatment. The survival rate in wet cotton ball treatment was the lowest. Nymph duration in rice stem treatment was significantly shorter than the other two treatments, which indicated that kidney bean and wet cotton ball significantly impact the growth of T.chinensis. Though the fecundity in kidney bean treatment was significantly lower than those in rice treatment, the longevity, egg hatching rate and nymphal survival rate in kidney bean treatment were similar with those in rice stem treatment, and were significantly higher than those in wet cotton ball treatment. The population trend index of T. chinensis on rice stem and kidney bean treatment was 22.9 and 11.2 respectively, which meant T. chinensis could build a continuous population efficiently. The results indicated that kidney bean could be used as a feasible survival substitute for T. chinensis.

Key words: rice, predator, kidney bean, reproduction, growth and development