Metabolic alterations in leaves of oxalate-rich plant Rumex obtusifolius L. irradiated by gamma rays

Abstract

Oxalate in some plants is toxic to vertebrates and causes kidney failure. In the present study, we investigated on the metabolic effectiveness of gamma ray irradiation to seeds of Rumex obtusifolius, which are known to accumulate high level of soluble oxalate, to lower oxalate accumulation in leaves. Reduced rate of germination, discoloration of cotyledons, and deformed true leaves were observed by elevated irradiation. Metabolome analysis of primary metabolites using capillary electrophoresis–mass spectrometry showed a decrease in oxalate contents in the leaves of plants from gamma ray-irradiated seeds. Moreover, organic acids such as malate and 2-oxoglutarate also decreased, whereas amino acids such as glutamate and glutamine increased. These results indicated that seed irradiation by gamma rays leads to dynamic changes in metabolic pathways as well as plant growth/development.