Abstract
Change of environmental conditions induces various biochemical and physiological responses in plants. Various substances are accumulated under chilling and drought conditions. The expression levels of several genes involved in biosynthesis of metabolites also increase under chilling and drought conditions. We carried out comparative analyses of both metabolites and transcripts in rice plants under chilling and drought conditions. Metabolite analyses were performed using GC-TOF-MS, CE-ESI-MS and LC-IT-MS. Identified metabolites were statistically compared by using principal component analysis. Then, we selected candidates of critical factors under chilling and drought conditions. Transcriptome analyses were performed using a 44K rice oligo array. We found that genes encoding several metabolic key enzymes were induced under chilling and/or drought conditions. A clear correlation was observed between induction of the genes encoding starch-degrading enzymes, sucrose metabolism enzymes and sugar alcohol synthase and increase of monosaccharide, disaccharide and sugar alcohols in rice plants.
