Heat-shock positively modulates oxidative protection of salt and drought-stressed mustard (Brassica campestris L.) seedlings

Abstract

ResearchOpen AccessHeat-shock positively modulates oxidative protection of salt and drought-stressed mustard (Brassica campestris L.) seedlings AbstractA large number of studies have shown the existence of cross-tolerance in plants, but the exact physiological and biochemical mechanism(s) is poorly understood. In this study, heat-shock (42 °C, 5 h) induced salinity and drought tolerance and possible involvement of antioxidative and glyoxalase systems were investigated in mustard (Brassica campestris L.) seedlings. Seven-day-old seedlings were subjected to salt (150 mM NaCl, 48 h) and drought stress (induced by 20% PEG, 48 h) with or without heat pretreatment. Both salt and drought stresses led to a severe oxidative stress as indicated by profound increases in hydrogen peroxide (H 2 O 2 ) and malondialdehyde (MDA) levels. A significant increase in ascorbate (AsA) content was observed in response to drought stress but the glutathione (GSH) and glutathione disulfide (GSSG) contents increased in response to both salt and drought stress. The GSH/GSSG ratio decreased significantly in response to drought stress. Salt stress led to a significant increases of ascorbate peroxidase (APX), glutathione reductase (GR), glutathione S-transferases (GST) activities; whereas, catalase (CAT) and glyoxalase II (Gly II) activities decreased. Drought stress resulted in a significant increase in monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), glutathione peroxidase (GPX) and glyoxalase I (Gly I) activities; whereas, CAT and Gly II activities decreased. Seedlings primed with heat-shock positively modulates the activities of APX, DHAR, GR, GST, GPX, CAT, Gly I and Gly II, and maintained lower levels of GSSG, H 2 O 2 and MDA as compared to the control mostly also salt and drought-stressed seedlings. Our results showed that a retention of the imprint of previous stress exposure (heat-shock) protects the plants from salt and drought-induced oxidative stress by stimulation of antioxidative and glyoxalase defense systems.

Phenotyping of mungbean (Vigna radiata L.) genotypes against salt stress and assessment of variability for yield and yield attributing traits

“…In support of our findings, decreases in yield and its associated characters in response to salt stress were reported in mungbean [31,32,33,34,28]. Low yield observed under salinity was probably due to the reduction of assimilate production, reduction of the mobilization of photosynthetic products in addition to altered cytosolic metabolism [35,36,37,38,39]. However, few genotypes showed better performance under salt stress conditions indicating their salt tolerance capabilities probably through the modulation of stress responsive pathways.…”

Unraveling the molecular basis of oxidative stress management in a drought tolerant rice genotype Nagina 22

“…Disequilibrium between ROS production and antioxidant protection causes oxidative stress, and the accumulating ROS causes peroxidation of lipids, denaturation of proteins, mutation in DNA sequence and various other types of cellular oxidative damage [ 10 – 13 ]. Enhanced generation of ROS has been found in plants under a variety of abiotic stresses, such as salt, drought, chilling, heat, and metal or metalloid stresses [ 14 – 18 ].…”

Alleviation of Drought Stress in <i>Arabidopsis thaliana</i> by 17<i>β</i>-Estradiol Application

“…Induction of drought stress by the application of PEG-6000 to the seedlings of Brassica campestris and B. juncea resulted in increased GSSG levels. B. juncea seedlings, in the presence of PEG-6000, displayed elevated levels of GSH as well [24] [25]. It is possible that ES alleviates the detrimental effects of drought stress in Arabidopsis by influencing the GSH-GSSG cycle.…”