Responses to drought induced oxidative stress in five finger millet varieties differing in their geographical distribution

Abstract

The study presents the impact of drought stress on five finger millet varieties (PR202, VL146, VL315, PES400 and VR708), representing contrasting areas of Indian sub-continent. Drought stress induced increase in the activity of superoxide dismutase, ascorbate peroxidase and glutathione reductase was higher in PR202 and VL315, while the activity was lower in the varieties PES400 and VR708. Ascorbate peroxidase : superoxide dismutase ratio, which is a crucial factor in alleviating drought stress, was higher in varieties PR202 and VL315, whilst the varieties PES400 and VR708 exhibited a lower ratio under stress. The variety PES400 recorded maximum stress induced damage, as indicated by higher accumulation of malondialdehyde and hydrogen peroxide; whereas the variety PR202 recorded least stress induced cytotoxic damage. The results clearly indicate that better drought tolerance of the variety PR202 is positively related to the capacity of its antioxidant system to scavenge reactive oxygen species, resulting in a reduced incidence of oxidative damage. Ascorbate peroxidase : superoxide dismutase ratio is found to be a critical factor governing the stress tolerance potential of different varieties. Therefore, varieties PR202 and VL315 were found to be tolerant while PES400 was susceptible to drought stress.

Oxidative stress induced expression of monodehydroascorbate reductase gene in Eleusine coracana

“…These ROS are also produced during the normal course of cellular metabolism, but their level is kept under control due to the presence of an effective anti-oxidative defence system. However, under stress, the production of ROS overrides the rate of their detoxification, and causes oxidative stress (Bhatt et al 2011). Excess accumulation of ROS negatively effects the growth and productivity of crop plants by interfering with various metabolic activities, resulting in protein oxidation, lipid peroxidation and damage to the nucleic acids; which under severe conditions may also lead to cell death.…”

Impact of arbuscular mycorrhizal fungus, Glomus intraradices, Streptomyces and Pseudomonas spp. strain on finger millet (Eleusine coracana L.) cv Korchara under water deficit condition

“…Wheat and rice provide food security, but crops like finger millet promise nutritional security for the world (Bhatt et al, 2011). Drought, a situation of severe water deficit, recurrently occurs in various parts of the world, often with devastating effects on crop productivity.…”

Effects of Paraquat-induced oxidative stress on antioxidants and Chlorophyll Fluorescence in stay-green wheat (Triticum aestivum L.) flag leaves

“…Paraquat was used to simulate the ROS-induced damage caused by other environment stresses, such as drought, heat and salinity (Chia et al 1981, Bhatt et al 2011. The development of paraquat-resistant varieties could be an effective strategy to counteract various environmental stresses and ensure high crop yields.…”