Volatile Profiles as Affected by Rice Brown Plant Hopper and Yellow Stem Borer in Rice Land Races

Rice (Oryza sativa L.,) plants release a complex profile of volatile organic compounds. Present study investigates the differences in volatile compounds from four rice landraces viz., Karuthakar, Norungan, Thavala Kanan and Varappu Kudaichan each under four conditions like healthy, mechanically damaged, and the ones infested by the brown plant hopper Nilaparvata lugens Stal and yellow stem borer Scirpophaga incertulas (Wlk.). The volatiles were collected using air entrainment method and characterized by the GCMS. Statistical analysis tools like clustering, principal component analysis and partial least square discriminant analysis were applied. Clear differences among the treatments were observed and certain volatile compound groups like terpenoids (squalene), unsaturated fatty acids (n-hexadecanoic, tetradecanoic and pentadecanoic acids), alkanes (heptacosane, tetracosane) were found. The statistical test of Partial Least Square Discriminant Analysis was found to be satisfactory in determining the compounds responsible for variations in treatments.