show Abstracthide AbstractUtilization of genetic resource is a key to successfully improve crop productivity while conserving water use. While photosynthesis and transpiration are regulated by both biotic and abiotic factors, plants with different genetic backgrounds may exhibit different environmental responses of photosynthesis and transpiration. It is known that field grown plants regulate gene expressions under dynamically changing environment. It is also known that different organs, such as leaf and root, have their unique characteristics in the gene expressions. This research aims to identify the gene species in leaves and roots, the expression of which is related to the variations of photosynthesis and transpiration of rice plants under two CO2-enrichment experiments: the free-air CO2 enrichment (FACE) experiment and the temperature gradient chamber (TGC) experiment.