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.

Naturally occurring plant toxins, such as benzoates, have been shown to have insecticidal effects on some pest insects. In this study three commercially available benzoates, methyl benzoate (MB), ethyl benzoate (EB), and vinyl benzoate (VB), were assessed for their contact toxicity against Aphis gossypii Glover and its lacewing predator Chrysoperla carnea Stephens. Toxicity of 1% MB, EB, and VB showed 100%, 85% and 60% mortality of A. gossypii at 24 h. In addition, a mixture of MB and EB showed higher synergistic effect than mixtures of MB+VB or EB+VB against A. gossypii. Toxicity at 1% concentration of three benzoates against A. gossypii showed lower toxicity against the larvae of C. carnea after 72 h of exposure than A. gossypii. Our result suggest that benzoates have high potential as environmentally safe biopesticides for A. gossypii control.

Methyl benzoate (MB) is a natural compound in many plants and shows insecticidal toxicity against various insect pests. We determined contact, fumigant, and repellent activities of MB against the sweetpotato whitefly Bemisia tabaci and the greenhouse whitefly Trialeurodes vaporariorum (Hemiptera: Aleyrodidae). Complete contact mortality was obtained by 4% MB. Contact mortality at 2% MB into eggs, 4th instar nymphs and adults were 69.4%, 91.6% and 80%, respectively. Fumigation of 2% MB killed 95% of adults. In addition, treatment of 4% MB repelled 60% adults. There was no significant different between two species. Our results suggest that MB has high potential as an natural pesticide for sustainable pest management in crop production.

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.