Gas Chromatography Mass Spectrometry based metabolomic investigation on five different rice cutivars (Oryza sativa L.) under different induced Cadmium stress

Abstract

Heavy Metals (HMs) are naturally occurring elements with high atomic weight and density. In this study, the metabolite profiling of five different indica rice varieties namely, IR-36, Triguna, IR-64, Muktasree and Ajit exposed to cadmium stress in concentrations from 0 µmolL−1, 25 µmolL−1, 50 µmolL−1 and 100 µmolL−1 has been performed using GC-MS. The score plots of PCA, PLS-DA and OPLS-DA analyses showed clear discrimination between control and Cd-treated seedlings of each variety. GC-MS based metabolomic study specified that HM like cadmium exposure could cause changes in metabolite levels mainly on amino acids, organic acids, sugars and their derivatives, phenolics, nitrogen bases and purine metabolites. These metabolomic responses are related with a reduction in shoot and root growth i.e, their photosynthetic capacity especially in IR-36, Triguna, IR-64 and Ajit variety. Only Muktasree showed a consistent increase in shoot and root length in the course of Cd exposure. Biochemical pathway analyses also demonstrated that exposure to cadmium affected the secondary metabolism pathways along with primary metabolism.