Subject(s)
Ziziphus , Ziziphus/genetics , Salt Tolerance/genetics , Fruit , Genetic Variation , SalinityABSTRACT
Fruit orchards are frequently irrigated with brackish water. Irrigation with poor quality water is also a major cause of salt accumulation in soil. An excess of salts results in stunted growth, poor yield, inferior quality and low nutritional properties. Melatonin is a low molecular weight protein that shows multifunctional, regulatory and pleiotropic behavior in the plant kingdom. Recently, its discovery brought a great revolution in sustainable fruit production under salinity-induced environments. Melatonin contributed to enhanced tolerance in Zizyphus fruit species by improving the plant defense system's potential to cope with the adverse effects of salinity. The supplemental application of melatonin has improved the generation of antioxidant assays and osmolytes involved in the scavenging of toxic ROS. The tolerance level of the germplasm is chiefly based on the activation of the defense system against the adverse effects of salinity. The current study explored the contribution of melatonin against salinity stress and provides information regarding which biochemical mechanism can be effective and utilized for the development of salt-tolerant germplasm in Zizyphus.
ABSTRACT
Lettuce (Lactuca sativa L.) production is low because of different environmental stresses. Salt stress significantly reduces lettuce growth and yield. Foliar application of ascorbic acid is considered as a possible way to mitigate the adverse salinity effects on plants. This current study investigated the effect of foliar spray of ascorbic acid (control, 100, 200, 300 and 400mg/L) to mitigate negative effects of salinity (0, 50, 100 and 150mMNaCl) in lettuce plants in 2019 and 2020. Salinity level of 200mMNaCl significantly reduced growth and yield traits; i.e. leaf length and diameter, number of leaves, fresh plant weight, number of roots, root length and root dry weight and these traits increased under foliar application of ascorbic acid concentration of 400mg/L. Two salinity levels (150 and 200mMNaCl)×400mg/L ascorbic acid enhanced superoxide dismutase (SOD) content in lettuce plants. Peroxidase (POD) content increased in 200mMNaCl and 400mg/L ascorbic acid. Catalase (CAT) content increased in 100, 150 and 200mMNaCl and 400mg/L ascorbic acid. Ascorbic acid was significantly greater in 200mMNaCl and 400mg/L ascorbic acid. Phenolic content was the maximum in 200mMNaCl and 300mg/L and 400mg/L ascorbic acid. Titratable acidity was higher in 0, 50, 100, 150 and 200mMNaCl and control of ascorbic acid. We conclude that ascorbic acid had potential to mitigate the adverse effects of salinity by reducing oxidative injury in agricultural crops especially lettuce.
