Exogenous Calcium Reinforces Photosynthetic Pigment Content and Osmolyte, Enzymatic, and Non-Enzymatic Antioxidants Abundance and Alleviates Salt Stress in Bread Wheat

Abstract

One of the main environmental stresses that hinder crop development as well as yield is salt stress, while the use of signal molecules such as calcium (Ca) has a substantial impact on reducing the detrimental effects of salt on different crop types. Therefore, a factorial pot experiment in a completely randomized design was conducted to examine the beneficial role of Ca (0, 2.5, and 5 mM) in promoting the physiological, biochemical, and growth traits of the wheat plant under three salt conditions viz. 0, 30, and 60 mM NaCl. Foliar application of Ca increased the growth of salt-stressed wheat plants through increasing photosynthetic pigments, IAA, proline, and total soluble sugars contents and improving antioxidant enzymes in addition to non-enzymatic antioxidants glutathione, phenol and flavonoids, β-carotene, and lycopene contents, thus causing decreases in the over-accumulation of free radicals (ROS). The application of Ca increased the activity of antioxidant enzymes in wheat plants such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), which scavenge reactive oxygen species (ROS) and relieved salt stress. An additional salt tolerance mechanism by Ca increases the non-antioxidant activity of plants by accumulating osmolytes such as free amino acids, proline, and total soluble sugar, which maintain the osmotic adjustment of plants under salinity stress. Exogenous Ca application is a successful method for increasing wheat plants’ ability to withstand salt stress, and it has a considerable impact on the growth of wheat under salt stress.

Effect of Abiotic Signals on the Accumulation of Saponarin in Barley Leaves in Hydroponics Under Artificial Lights

“…Na + and K + salts were known as ROS regulation factors in plants, ,,− and these might affect the saponarin biosynthesis in YBL. Thus, Na + as a ROS stimulator was used in the hydroponics, and the YBL growth and saponarin contents were measured under 6500 K light conditions.…”

Induction of tolerance in groundnut plants against drought stress and Cercospora leaf spot disease with exogenous application of Arginine and Sodium nitroprusside under field condition

“…The decreases in groundnut were coincided with signi cant declines in growth indices (Table 1) and photosynthetic pigments (Table 2). As a consequence, low carbohydrates buildup or a slowing down of the amount at which carbohydrates are transported from leaves to growing seeds are required for seeds lling (Sadak et al, 2023). Because carbohydrates have a direct impact on other physiological processes like respiration, changing carbohydrates content is very crucial.…”

Thymol Deploys Multiple Antioxidative Systems to Suppress ROS Accumulation in Chinese Cabbage Seedlings under Saline Stress

“…Seedlings with a 1 cm root were transferred to a Petri dish with three filter papers saturated with Hoagland nutrition (1/4 strength). NaCl (25, 50, 100, 200 mM) or thymol (5,10,20,40) was mixed with the Hoagland nutrition to treat the seedlings. The seedlings grew in the same incubator as mentioned above.…”

“…These biostimulants facilitate saline tolerance via the regulation of plant intrinsic physiology, including the redox balance, photosynthesis reinforcement, osmotic adjustments, and carbohydrate metabolism, etc. [20][21][22] The salt-resistant function of biostimulants has been identified, but the potentiality of applying them in agriculture remains elusive due to limited environmental adaptations. Therefore, developing novel biostimulants that can be used in agriculture is still needed.…”