Effect of Salt Stress and Foliar Application of Salicylic Acid on Morphological, Biochemical, Anatomical, and Productivity Characteristics of Cowpea (Vigna unguiculata L.) Plants

Abstract

The present study aimed to investigate the impact of salinity on vegetative growth, chemical constituents, and yields of cowpeas (Vigna unguiculata) and the possible benefits of salicylic acid (SA) on these plants after damage from salinity. To achieve these objectives, two pot experiments were carried out at the Faculty of Agriculture, Al-Azhar University, Egypt, during the two growing seasons of 2019 and 2020. The results revealed that salinity significantly decreased, and SA treatment substantially increased the plant height, number of compound leaves, number of internodes per plant, fresh weights of leaves and stems, productivity, photosynthetic pigments content, and concentrations of nitrogen (N), phosphorus (P), and potassium (K) of the cowpea plants compared with the control. The anatomical structure of stems and leaves of the plants were also investigated, and it was found that positive variations in the anatomical structure of the median portion of the main stems and blades of mature foliage leaves were detected in the stressed and SA-treated plants. In conclusion, SA treatment increased the salt stress tolerance of cowpea plants by improving the morphological and physiological attributes of the plants.

Physiological and biochemical responses of Tanacetum balsamita L. to the foliar application of Dobogen biostimulant, glucose and KNO3 under salinity stress

“…KNO 3 foliar application under the salinity stress improved N and K content of plants while reducing the Na/K ratio 30 . Similar results on the enhanced potassium levels under a saline environment and foliar SA spray have been reported in Vigna unguiculata 42 . Under saline-sodic conditions, Na + enters the apoplastic lumens and, with substitution of Ca 2+ ions in the cell membranes, depolarizes membranes and interferes with the selective absorption of essential minerals 43 , 44 .…”

“…Salinity negatively influenced SOD activity in Gossypium hirsutum 39 . Foliar application of SA improved SOD activity in saline environments 42 . SOD is in the front line of struggling with the damages caused by ROS radicals and acts by converting O 2 − into H 2 O 2 43 .…”

Morpho-Physiological and Anatomical Alterations of Salt-Affected Thompson Seedless Grapevine (Vitis vinifera L.) to Brassinolide Spraying

“…Nutrient concentrations of grapevine seedlings except Na + drastically decreased under salinity; however, BL application mitigated salinity injuries via dropping Na + and increased N, P and K (Table 2). The outcomes were compatible with El-Taher et al [7], Sarwar et al [10], Hatami and Pourakbar [17] for salinity, Kolomeichuk et al [27], and Karlidag et al [64] for BL. Accordingly, Miao et al [65] proved that BRs application improved root nodulation capacity and nitrogenase activity, resulting in increasing N% in plant tissues.…”

“…Plants undergo salinity critically once they are grown in saline conditions. The drastic impact of salinity as recorded in the current investigation on plant growth was provided with earlier findings for numerous plants [6][7][8]11,16,17]. The overall decline under salinity might be caused by the negative impact of salinity on different metabolic processes and molecular alterations, i.e., photosynthesis, nutrient homeostasis, stomatal resistance, and ROS production in different plants [6,8,16].…”

“…Salinity is considered one of the prime exigent environmental threats against sustainable food production [6][7][8]. About 33% of irrigated croplands are classified as salt-affected soil, which may exceed 50% by 2050 [9].…”