Differential activity of the antioxidant defence system and alterations in the accumulation of osmolyte and reactive oxygen species under drought stress and recovery in rice (Oryza sativa L.) tillering

Abstract

The objective of this study was to investigate the effects of drought stress on the activity of antioxidant enzymes and osmotic adjustment substance content in the tillering period of drought-sensitive and drought-tolerant rice cultivars. The results showed that the superoxide dismutase (SOD), peroxidase (POD), catalase activity (CAT), hydrogen peroxide content, soluble protein content and soluble sugar content increased with the accumulation of time and intensity of drought stress. Compared with the drought-sensitive cultivar, drought-resistant cultivar had a smaller photosynthetic affected area, longer CAT enzyme activity duration, and lower H 2 O 2 accumulation. Unlike POD and CAT enzymes, which maintain the ability to scavenge hydrogen peroxide under long drought conditions, ascorbate peroxidase (APX) enzymes seem to be a rapid response mechanism to scavenge hydrogen peroxide under drought stress. Under a −10 kPa water potential, using soluble sugars on the osmotic adjustment ability of the drought-resistant cultivars was more efficient; under −40 kPa water potential, drought-resistant cultivars can maintain relative high levels of ascorbate (ASA) content in the short term. After the restoration of irrigation, the indices gradually returned to control levels. The ASA content showed faster accumulation ability in drought-resistant cultivars and faster recovery. The soluble protein content recovered more slowly in drought-sensitive cultivars under the −40 kPa treatment. Drought-resistant cultivars showed stronger resistance to drought in the −10 kPa treatment and obtained similar yield to the control, while the drought-sensitive cultivars were more obviously affected by the drought stress.

Reactive oxygen species scavenging mechanisms associated with polyethylene glycol mediated osmotic stress tolerance in Chinese potato

“…Our results also showed that ascorbate-glutathione cycle (ASA-GSH) played an important role on scavenging the over production of H 2 O 2 due to osmotic stress in Chinese potato genotypes. APX, GR, MDAR and DHAR involved in ASA-GSH cycle were also higher in stressed plants than that in control 39,41 . This series of enzymatic and non-enzymatic antioxidants such as SOD, CAT, GPX and DHAR delays leaf senescence induced by PEG stress 42 .…”

“…Khanna-Chopra and Selote 38 reported a higher level of antioxidative machineries in stressed plants over non-stressed plants. Similarly, Wang et al 39 reported that the osmotic adjustment ability in tolerant cultivar is more efficient over susceptible ones. SOD is the first line of antioxidant which rapidly scavenges O 2 and restricts the production of OH 40 .…”

“…ASA acts as an important defensive antioxidant against overproduction of ROS induced by oxidative stress 43,44 . Resistant varieties maintained higher ascorbate content over susceptible ones under different levels of drought www.nature.com/scientificreports www.nature.com/scientificreports/ stress 39 . This antioxidant plays a major role either in preventing or in lowering the risk caused by ROS in higher plants; by removal of H 2 O 2 via ASA-GSH cycle.…”

Plant Growth and Soil Microbial Impacts of Enhancing Licorice With Inoculating Dark Septate Endophytes Under Drought Stress

“…SOD, CAT, and POD are reportedly the most important enzymes involved in the removal of reactive oxygen species (ROS) (Hosseini et al, 2018). The increased activities of SOD and CAT in the PP-inoculated and FA-inoculated plants, and the increase of soluble protein content in the AV-inoculated and PP-inoculated plants at water stress indicated that the antioxidant enzyme activity and soluble protein level were enhanced to remove ROS under drought stress conditions (Hosseini et al, 2018; Wang et al, 2019). Using soluble proteins as compatible osmolytes can facilitate osmotic adjustment, leading to an increased tolerance to dehydration (Doganlar et al, 2010).…”

Identification of Drought Tolerant and Molecular Analysis of DREB2A and BADH2 Genes and Yield Potensial of Lines from Single Crossing Bengkulu Local Rice Varieties

“…Previous studies carried out by Sakamoto and Murata (2000) and Saxena et al (2019) indicated that osmoprotectant substances, such as glycine betaine, play an essential role in cell stabilization by balancing the structure of the protein quaternary and membrane structure against the adverse effects of salinity. Besides, it facilitates osmotic adjustment by lowering the internal osmotic potential, which contributes to the ability to tolerate water pressure, stabilizing the PSII and RuBisCO complexes in the process of photosynthesis under seizure conditions (Holmström et al 2000;Wang et al 2019;Huang et al 2020). The positive effects and exogenous application of glycine in plants grown under salinity stress conditions have been shown to protect plant cells (Demiral and Türkan 2004;Saxena et al 2019).…”