Salinity threatens crop cultivation and productivity worldwide; however, to improve salinity tolerance in crop plants, foliar application of bio‐stimulants is thought to be a worthwhile technology. The current study was carried out to reveal the impact of foliar‐applied amino acids, phenylalanine (75 and 100 mg L −1 ) and methionine (25 and 50 mg L −1 ) on osmolyte accumulation, antioxidant activity, and yield of four cucumber genotypes (HC‐999, Valley, NSC‐CM1, and Akbar) under salt stress (100 mM NaCl). Regarding the individual effects, foliar spray of 50 mg L −1 methionine significantly enhanced the yield production of all cucumber genotypes; whereas foliar spray of phenylalanine at 100 mg L −1 significantly enhanced the antioxidant activity and osmolytes accumulation under salinity stress in comparison to other treatments. Combined amino acids (methionine at 25 mg L −1 and phenylalanine at 100 mg L −1 ) application significantly increased the fruit weight and antioxidant activity in saline conditions as compared to all other treatments. Among the genotypes, Valley was the most tolerant to salt stress as compared to the others. Overall, 25 mg L −1 methionine with 100 mg L −1 phenylalanine can be recommended for the farming community to avoid the yield loss of cucumber in salt‐affected soils.
Marium et al. (Fri,) studied this question.