INSECTICIDAL PROPERTIES OF SPODOPTERA EXIGUA NUCLEAR POLIHEDROSIS VIRUS LOCAL ISOLATE AGAINST SPODOPTERA EXIGUA ON SHALLOT

Abstract

To date, beet army worm (BAW) (Spodoptera exigua Hubn.) is the most important pest on shallot in the world, and also in Indonesia. So far, in Indonesia, the pest was controlled using chemical insecticides which caused damage on environment and consumers. Spodoptera exigua nuclear polihedrosis virus (Se-NPV) is virus that specifically infects BAW, so it could be developed as biological control agent against the BAW. The research was conducted at Plant Protection Laboratory and Greenhouse of Agriculture Faculty, Sebelas Maret University, Surakarta, Indonesia from September 2011to August 2012. The aims of this research were to evaluate the potency of Se-NPV local isolate in controlling BAW in laboratory and green house. In this research, we also evaluated potency of non-native pathogen Mythimna separata nuclear polihedrosis virus (Ms-NPV) in controlling BAW. Chemical insecticide Lamda Sihalotrin was used as a comparison. The results showed that application of Se-NPV was effective enough in controlling BAW both in the laboratory and green house experiment. In laboratory experiment, Se-NPV caused larvae mortality by 77.5% within 5 days. Furthermore, Se-NPV also suppressed BAW feeding capacity by 0.43 g per day. Moreover, Se-NPV also decreased pupae weight by 0.063 g.  In green house experiment, the application of Se-NPV could cause 100% of larval mortality, and decrease damage intensity of shallot caused by BAW by 10.43%.  Interestingly, in this experiment Ms-NPV which is not a native pathogen caused higher BAW mortality than Se-NPV.