Exogenous γ-aminobutyric acid (GABA) mitigated salinity-induced impairments in mungbean plants by regulating their nitrogen metabolism and antioxidant potential

Abstract

BackgroundIncreasing soil salinization has a detrimental effect on agricultural productivity.Therefore, strategies are needed to induce salinity-tolerance in crop species for sustainable foodproduction. γ-aminobutyric acid (GABA) plays a key role in regulating plant salinity stresstolerance. However, it remains largely unknown how mungbean plants (Vigna radiata L.) respondto exogenous GABA under salinity stress.MethodsThus, we evaluated the effect of exogenous GABA (1.5 mM) on the growth and physiobiochemicalresponse mechanism of mungbean plants to saline stress (0-, 50-, and 100 mM [NaCland Na2SO4, at a 1:1 molar ratio]).ResultsIncreased saline stress adversely affected mungbean plants' growth and metabolism. Forinstance, leaf-stem-root biomass (34- and 56%, 31- and 53%, and 27- and 56% under 50- and 100mM, respectively]) and chlorophyll concentrations declined. The carotenoid level increased (10%)at 50 mM and remained unaffected at 100 mM. Hydrogen peroxide (H2O2), malondialdehyde(MDA), osmolytes (soluble sugars, soluble proteins, proline), total phenolic content, andenzymatic activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), peroxidase(POD), glutathione reductase (GTR), and polyphenol oxidation (PPO) were significantlyincreased. In leaves, salinity caused a significant increase in Na+ concentration but a decrease inK+ concentration, resulting in a low K+/Na+ concentration (51- and 71% under 50- and 100- mMstress). Additionally, nitrogen concentration and the activities of nitrate reductase (NR) andglutamine synthetase (GS) decreased significantly. The reduction in glutamate synthase (GOGAT)activity was only significant (65%) at 100 mM stress. Exogenous GABA decreased Na+, H2O2,and MDA concentrations but enhanced photosynthetic pigments, K+ and K+/Na+ ratio, Nmetabolism, osmolytes, and enzymatic antioxidant activities, thus reducing salinity-associatedstress damages, resulting in improved growth and biomass.ConclusionExogenous GABA may have improved the salinity tolerance of mungbean plants by maintaining their morpho-physiological responses and reducing the accumulation of harmfulsubstances under salinity. Future molecular studies can contribute to a better understanding of themolecular mechanisms by which GABA regulates mungbean salinity tolerance.

Salicylic Acid and α-Tocopherol Ameliorate Salinity Impact on Wheat

“…Besides, there is a link between decreased growth and a reduction in photosynthesis and the uptake of essential ions. 13,51 Salinity-induced impairments in growth features have been reported in several studies, 5,7,30,44,52 which supports our findings. However, the foliar application of SA and TP alleviated the adverse effects of salinity by improving these growth characteristics.…”

“…Salinity (environmental stress) limits the growth and development of plants. , Salinity stress in plants (xylem) disrupts water flow to nearby elongating cells, suppressing cell elongation. Salinization generally causes a high accumulation of salt ions, including Na + and Cl – ions, leading to ionic toxicity, osmotic imbalance, impaired nutrient acquisition, metabolic disruption, excessive reactive oxygen species (ROS) production, and oxidative stress damage. ,, Plants have developed complex mechanisms to respond and adapt to stress conditions, including salinity stress, via their cellular, physiological, and molecular mechanisms. − For instance, several physiological processes have been shown to relate to salinity tolerance, including osmotic adjustment, ionic homeostasis, nutrient uptake, antioxidant enzyme and metabolite systems, and hormone regulation. − Salinity stress affects the production of ROS and antioxidant-mediated metabolism in plants. Excessive ROS such as O 2 ·– H 2 O 2 and OH can cause degradation of protein, lipids, and macromolecules, causing metabolic arrest in the cell.…”

Molecular Characterization of Germin-like Protein Genes in Zea mays (ZmGLPs) Using Various In Silico Approaches

“…However, still, their function is not fully understood. GLPs are expressed in all types of tissues (flowers, seeds, roots, stems, leaves, and embryos) by playing a pivotal role against diverse environmental stresses. , Previously, among abiotic stresses, they were found effective against heavy metals, , drought, , salt, , desiccation, heat, , abscisic acid (ABA), and UV radiation acclimation mediated by methylation in the promoter region as observed in rice . Among biotic stresses, they were active against herbivore-induced damage, Sclerotinia sclerotiorum (S.…”

The Impact of Trichoderma harzianum Together with Copper and Boron on Wheat Yield

“…Bread wheat ( Triticum aestivum L.) is an annual grass and essential cereal crop, resulting from a cross between Triticum turgidum L. and Aegilops tauschii . − It is an important food and essential source of nutrition, used as a staple food for humans, providing approximately 20% of the food calories and 55% carbohydrates, with an annual consumption of about 35% around the globe. − The requirements of wheat will be increased by 50% at the end of 2050 because of rapidly growing world population. , Changing climate and different environmental stresses have severely affected food production worldwide. − Like other plants, wheat growth is harshly affected by various biotic and abiotic factors, hence, limiting its yield and quality. − Higher demand of food and fiber is the major cause of using synthetic pesticides and chemical fertilizers for increasing yield . Further, wheat yield can be enhanced by maximum productivity, not by increasing the agricultural land, and accordingly, nutrient management is believed to be among the important factors for wheat improvement. − …”