Exogenous hydrogen peroxide enhanced the thermotolerance of Festuca arundinacea and Lolium perenne by increasing the antioxidative capacity

Abstract

Heat stress is one of the most detrimental environment stresses for plants. Hydrogen peroxide (H 2 O 2 ) is produced quickly in response to various stresses and likely plays a positive role in transmitting stress signal in organisms. This investigation addressed whether an exogenous H 2 O 2 application would affect the heat response of turfgrasses and induce acclimation. Tall fescue (Festuca arundinacea cv. Barlexas) and perennial ryegrass (Lolium perenne cv. Accent), two important cool-season turfgrasses and forages, were sprayed with 10 mM H 2 O 2 before they were treated with heat stress (38/30°C, day/night) and compared with plants maintained at control temperatures (26/15°C, day/night). Prior to the initiation of heat stress, H 2 O 2 pretreatment increased the activities of guaiacol peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR) and glutathionedependent peroxidase (GPX) and the ascorbate and glutathione pool, and it decreased the GSH/GSSG ratio. During the heat stress process, pretreated plants from both grasses exhibited higher turfgrass quality and relative water content, and they experienced lower oxidative damage and H 2 O 2 levels. Moreover, the activities of APX, GR, GPX and glutathione-S-transferase increased significantly in response to H 2 O 2 pretreatment under heat stress. These results suggested that H 2 O 2 most likely participated in the transduction of redox signaling and induced the antioxidative defense system, including various enzymatic and nonenzymatic H 2 O 2 scavengers. The scavengers played important roles in improving the thermotolerance of tall fescue and perennial ryegrasses.

Cadmium stress antioxidant responses and root-to-shoot communication in grafted tomato plants

“…5) was lower than in non-grafted plants, although the production of H 2 O 2 was increased (Fig. 6) in the leaves of grafted -Cd/?Cd plants, suggesting a regulatory role of ROS in the cross talks of stress signaling and redox metabolic signals (Golldack et al 2014;Wang et al 2014), which can be related to a quick response to the stress from rootstocks to scions of these grafted plants. Moreover, rootstocks of grafted ?Cd/-Cd showed increased MDA content when compared with rootstocks of selfgrafted -Cd/-Cd plants, which could also indicate stress signaling from scions to rootstocks.…”

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

“…High levels of H 2 O 2 generated during abiotic stress, including drought stress, can damage cellular structures but a low concentration of H 2 O 2 is maintained within the cells and functions as a signal, mediator or effector involved in developmental processes and stress responses [22] [30]. High levels of H 2 O 2 can by itself result in oxidative damage to the cells [21] but it has been demonstrated in a number of plants species, including maize [31], mustard [32], tall fescue and rye grass [33], that an increase in H 2 O 2 levels primes the plants for enhanced drought stress resistance. Significant increases in H 2 O 2 levels in 10 and 100 nM ES-treated Arabidopsis subjected to drought conditions were responses to drought stress and not to the ES treatment and it indicates that H 2 O 2 contributed to the enhanced drought stress tolerance of these plants.…”

Hydrogen peroxide priming modulates abiotic oxidative stress tolerance: insights from ROS detoxification and scavenging

“…Recent studies have shown that priming can also modulate abiotic stress tolerance (Filippou et al, 2012; Hossain and Fujita, 2013; Mostofa and Fujita, 2013; Borges et al, 2014; Mostofa et al, 2014a,b,c; Nahar et al, 2014; Wang et al, 2014a). Despite the agronomic and ecological importance of priming, in-depth molecular mechanisms associated with priming in plants are still unknown (Conrath, 2011).…”