Antifeedants of Indian Barnyard Millet, Echinochloa frumentacea Link, against Brown Planthopper, Nilaparvata lugens (Stål)

Eight compounds isolated from Indian barnyard millet have been identified as l-malic acid, trans-aconitic acid, (+)-isocitric acid, 5-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, isocarlinoside, 2″-O-rhamnosylisoorientin, and 7-O-(2″-O-glucuronosyl)glucuronosyltricin, respectively. These compounds showed high antifeeding activity against brown planthopper only when they were combined.