Spodoptera litura Fabricius is the serious, polyphagous pest of various crops. Due to the high resistant to most of chemical pesticides, it is hard to control S. litura in the fields. We investigated the virulence of four entomopathogenic nematodes (EPNs) in each larval stage. All EPNs were more effective to younger larvae than older larvae. Mortality, larval penetration rate and reproduction rate were significantly higher in H. indica, S. carpocapsae and S. longicaudum than the H. bacteriophora. Three high effective EPNs induced complete mortality of first instar larvae within 48 h, but of fifth instar larvae within 72 h. These EPNs also highly effective to control S. litura in pot assay. Thus, H. indica, S. carpocapsae and S. longicaudum, can be used as efficient biological control agents of S. litura.

Fungus gnat, Bradysia impatiens is the most serious pest of different vegetable crops, mushroom and ornamental crops. In this study, we compared the control efficacy of two entomopathogenic nematode; Steinernema carpocapsae and Heterorhabdistis indica in Bradysia impatiens last instar maggots at 25℃ in laboratory. Our present study shows that, nematode infection and reproduction both were higher in the warm adapted nematode H. indica than the cold adapted S. carpocapsae. Therefore, entomopathogenic nematode H. indica can be use for control the Badysia impatiens as the efficient biological control agent.

The sweetpotato whitefly Bemisia tabaci is one of the most serious pests in the greenhouse. They can infest variouscrop plants even in high warm greenhouse condition in summer. To understand the effect of heat acclimation ability ofB. tabaci, mortality was determined at various temperature conditions of the greenhouse. Adult whiteflies survived evenin 63°C in tomato greenhouse. The median lethal temperature (LT50) of the greenhouse colony was 59.9°C however LT50of the lab colony was 47.6°C. The relative expression level of heat shock proteins (hsp23, hsp70 and hsp90) were significantlylower in the greenhouse colony compare to the lab colony. This result suggests B. tabaci has very high thermal adaptability(acclimation) and its mechanism is associated with heat shock protein system.