Stress amelioration response of glycine betaine and Arbuscular mycorrhizal fungi in sorghum under Cr toxicity

Abstract

Chromium toxicity is a major problem in agricultural soils that negatively affects a plant’s metabolic activities. It reduces biochemical and antioxidant defence system’s activities. In search of the solution to this problem a two-year pot experiment (completely randomized design with three replications), in three genetically different varieties of sorghum (SSG 59–3, HJ 513 and HJ 541) under Cr toxicity (2 and 4 ppm) was conducted to determine the effect of glycine betaine (50 and 100mM) and Arbuscular mycorrhizal fungi (AMF) on the antioxidant system (enzymes viz. superoxide dismutase, ascorbate peroxidase, catalase, glutathione reductase, peroxidase and metabolites viz. glutathione, ascorbate, proline, β-carotene) along with Cr accumulation and indices of oxidative stress parameters (polyphenol oxidase, hydrogen peroxide and malondialdehyde) at two growth stages (vegetative and grain filling). According to results; Cr stress (2 & 4 ppm) increased its accumulation and indices of oxidative stresses significantly (p≤0.05) in all varieties of sorghum at both growth stages. However, soil application of glycine betaine (GB) and AMF decreased Cr accumulation and indices of oxidative stress by increasing antioxidant enzymes and metabolites activities at both growth stages in all varieties. The combination of 100mM GB with AMF was observed most significant (p≤0.05) in decreasing oxidative stress and improved the antioxidant system’s activities. The SSG 59–3 cultivar showed the lowest Cr accumulation (1.60 and 8.61 ppm), indices of oxidative stress and highest antioxidant system’s activity among these three cultivars at both growth stages. Thus, SSG 59–3 was found most tolerant cultivars followed by HJ 513 and then HJ 541. These findings suggest that both GB and AMF, either individually or combined can play a positive role to reduce oxidative stress and increased antioxidant attributes under Cr toxicity in sorghum.

How to Cope with the Challenges of Environmental Stresses in the Era of Global Climate Change: An Update on ROS Stave off in Plants

“…In salt-stressed sorghum, reductions were observed in MDA content, polyphenol oxidase (PPO) activity, and H 2 O 2 when treated with GB. However, Cr stress increased the liberation of ROS and intermediate products (OH − and H 2 O 2 ), which enhances the activity of PPO and MDA content in sorghum [173].…”

Activation of plant immunity by exposure to dinitrogen pentoxide gas generated from air using plasma technology

“…However, this type of approach might be useful for efficiently controlling plant diseases by exposing crop species to the appropriate active gas composition for the type of disease. Recently, Kumar and co-workers reported that glycine betaine and Arbuscular mycorrhizal fungi treatment reduces chromium toxicity via reduction of oxidative stress [55][56][57]. Combining such treatments with N 2 O 5 gas exposure may allow for the development of more effective and harmless disease control methods.…”

Harzianopyridone Supplementation Reduced Chromium Uptake and Enhanced Activity of Antioxidant Enzymes in Vigna radiata Seedlings Exposed to Chromium Toxicity

“…Glycine betaine is reported to alleviate numerous abiotic stresses in sorghum ( Kumar, 2021 ). The present study revealed that HZRP treatment alleviated Cr toxicity in V. radiata seedlings.…”