Foliar application of ascorbic acid enhances salinity stress tolerance in barley (Hordeum vulgare L.) through modulation of morpho-physio-biochemical attributes, ions uptake, osmo-protectants and stress response genes expression

Abstract

Barley ( Hordeum vulgare L.) is a major cereal grain and is known as a halophyte (a halophyte is a salt-tolerant plant that grows in soil or waters of high salinity). We therefore conducted a pot experiment to explore plant growth and biomass, photosynthetic pigments, gas exchange attributes, stomatal properties, oxidative stress and antioxidant response and their associated gene expression and absorption of ions in H. Vulgare . The soil used for this analysis was artificially spiked at different salinity concentrations (0, 50, 100 and 150 mM) and different levels of ascorbic acid (AsA) were supplied to plants (0, 30 and 60 mM) shortly after germination of the seed. The results of the present study showed that plant growth and biomass, photosynthetic pigments, gas exchange parameters, stomatal properties and ion uptake were significantly ( p < 0.05) reduced by salinity stress, whereas oxidative stress was induced in plants by generating the concentration of reactive oxygen species (ROS) in plant cells/tissues compared to plants grown in the control treatment. Initially, the activity of antioxidant enzymes and relative gene expression increased to a saline level of 100 mM, and then decreased significantly ( P < 0.05) by increasing the saline level (150 mM) in the soil compared to plants grown at 0 mM of salinity. We also elucidated that negative impact of salt stress in H. vulgare plants can overcome by the exogenous application of AsA, which not only increased morpho-physiological traits but decreased oxidative stress in the plants by increasing activities of enzymatic antioxidants. We have also explained the negative effect of salt stress on H. vulgare can decrease by exogenous application of AsA, which not only improved morpho-physiological characteristics, ions accumulation in the roots and shoots of the plants, but decreased oxidative stress in plants by increasing antioxidant compounds (enzymatic and non-enzymatic). Taken together, recognizing AsA's role in nutrient uptake introduces new possibilities for agricultural use of this compound and provides a valuable basis for improving plant tolerance and adaptability to potential salinity stress adjustment.

Bacillus mycoides PM35 Reinforces Photosynthetic Efficiency, Antioxidant Defense, Expression of Stress-Responsive Genes, and Ameliorates the Effects of Salinity Stress in Maize

“…Plant morphology, physiology, biochemistry, and molecular processes are affected by salinity stress [6]. Seed germination and plant development are negatively affected by the osmotic and ionic imbalances of Na + and Cl − [7].…”

S-Fertilizer (Elemental Sulfur) Improves the Phytoextraction of Cadmium through Solanum nigrum L.

“…As a result of metal accumulation, a large number of active free oxygen radicals are formed, which may be the main cause of cell membrane lipid peroxidation, and this also harms the functioning and structure of the cell membrane [76][77][78]. Excessive reactive oxygen species (ROS) production causes oxidative stress, as reported for many crops under heavy metals treatment, and is likely to be commenced by molecular oxygen excitation (O2), to generate singlet oxygen, or by electron transfer to O2 and the genesis of free radicals, i.e., O 2− and OH − [79][80][81]. Plant response to oxidative stress also depends upon plant species and cultivars, and this ROS production in plants is removed by a variety of antioxidant enzymes such as SOD, POD, CAT, and APX [82,83].…”

Ecotypic Morphological and Physio-Biochemical Responses of Two Differentially Adapted Forage Grasses, Cenchrus ciliaris L. and Cyperus arenarius Retz. to Drought Stress

“…Water stress induced secondary responses, i.e., production of enzymatic and non-enzymatic antioxidants, production of osmolytes, flavonoids, phytoalexins to cope with detrimental effects of drought by the up-regulation of oxidative defense mechanism and accumulation of osmolytes in the cell to maintain osmotic pressure [41]. Prolonged drought stress inhibited enzyme function and destroyed photosynthetic apparatus due to the high production of reactive oxygen species (ROS) in photosystems [42,43]. The level of chlorophyll contents in photosystems is an indication of normal functioning of photosynthetic processes and severely affected when subjected to water shortage.…”