Botanical insecticide of chili and ginger extract on Nilaparvata lugens, brown planthopper

Abstract

Invasion of Nilaparvata lugens or brown planthopper (BPH) in paddy fields has led to the use of excessive chemical insecticides due to its effectiveness. However, excessive applications has contributed several negative effects on the environment, farmers as well as non-targeting organisms. As an alternative, a mixture of a botanical insecticide containing mixture of chili and ginger extracts have been studied. Three parameters were studied namely the extract concentration, time of exposure and temperature of exposure. The results showed that 90% of BPH mortality was found at 40% extract concentration with 72 hr duration time of exposure at optimal temperature 30 C. HPLC analysis proved the presence of capsaicin and gingerol at peaks of 4.502 min and 11.046 min respectively. From repellency analysis, the BPH showed selective repel action against the treated paddy. This is due to the pungent odor contributed from compound of gingerol, shogaol and capsaicin presented in the mixture. Meanwhile, contact toxicity studies have successfully give 100% of mortality of BPH. Microscopic analysis have shown BPH deformities was increased by the extract concentration.