Physiological processes associated with the resistance of Glycine max (Merr., L.) plants to repeated water stress

Abstract

The experimental data were obtained on the reasoning behind the meaning of water homeostasis significance and antioxidant protection in the event of potential resistance of Glycine max L.(Merr) plants to the hydric and oxidative stresses, conditioned by in time repeated drought. It was established that the primary reaction of soybean plants to drought action is changing the parameters of the water status and tissue dehydration, coupled with the formation of reactive oxygen species (ROS), an increase of malonic dialdehid (DAM) and peroxide oxidation of lipids. Dehydration and ROS formation causes destruction of chloroplasts and diminish fund assimilating pigments in the leaves of both cultivars, especially in sensitive plants.Water stress caused closure of the stomata, the inhibition of carbon dioxide assimilation, with the negative consequences on the of water use efficiency in the production process. The plants, which have suffered a moderate drought at the initial stages of ontogenesis, exhibit a greater tolerance to repeated drought during critical period.