Evaluation of prey for the mass produced predator, Sycanus dichotomus Stal. (Hemiptera: Reduvidae) in single species and mixed species diets

Sycanus dichotomus Stal. (Hemiptera: Reduvidae) is a generalist predator with a wide food spectrum which is commonly found attacking the bagworms and nettle caterpillars in oil palm plantations. This predator may therefore be a valuable biological agent for the control of both pests. Laboratory studies have been conducted to evaluate the suitability of Tenebrio molitor larvae, Corcyra cephalonica larvae and mixed preys of T. molitor larvae and C. cephalonica larvae as food sources for Sycanus dichotomus. The impacts of prey consumption on the predator's population growth parameters were studied. The growth parameters involved in this study were developmental time, body weight and femur length. Laboratory tests revealed that among all food sources given, mixed diet performed better in supporting the growth and development of S. dichotomus. Different food sources showed different degrees of suitability: C cephalonica reduced the early nymphs' developmental period (stages 1 and 2) but reduced the adult longevity compared with T. molitor. The result evidently indicated that C cephalonica represents a suitable dier for early nymphs' development (stage 1 and 2), but mixed diet was more suitable as food for the final nymphs (stage 3 - 5) and adults longevity. The acceptability of all life stages of C. cephalonica was observed. The predator's body weight was noted to increase when supplied with the mixed preys. A quick growth response to nymphs' developmental stages was observed in response to the mixed preys (94.9 days) over C. cephalonica and T. molitor diet alone which were 97.6 and 116.1 days, respectively. The results revealed that the nutritional quality of different prey species could significantly influence the growth and development of S. dichotomus.