Ameliorative Effect of Foliar Nutrient Supply on Growth, Inorganic Ions, Membrane Permeability, and Leaf Relative Water Content of Physalis Plants under Salinity Stress

The effects of nutrients foliarly applied at varying doses were investigated on some agrophysiological properties, such as dry matter, nutrient content, chlorophyll content, membrane permeability, and leaf relative water content, of physalis (Physalis ixocarpa) plants under salinity stress. Plant shoot fresh weight, dry weight, plant length, and chlorophyll contents were reduced by 54.0-61.8%, 53.4-64.8%, 38.3-47.0%, and 26.5-40.0%, respectively, at 60 and 120 mM (without foliar application) compared to the nonsaline treatment [0 mM sodium chloride (NaCl)]. However, the membrane permeability (MP) of the plants increased with increasing salinity. Ion balance in plant cells is very important to plant growth and tolerance of salinity. So, foliar application alleviates to some extent the deleterious effects of salinity stress on growth and growth parameters, depending on nutrient concentration in plant. The greatest mitigating effects of foliar fertilizer for chlorophyll, shoot fresh weight, leaf relative water content, and MP at high-salinity-stress conditions (60 and 120 mM) were obtained from a 10-mM foliar magnesium nitrate [Mg(NO3)2] application at the ratios 57.2-62.6%, 49.0-30.9%, 27.5-28.9%, and 33.0-19.6%, respectively, but 10-mM foliar calcium nitrate [Ca(NO3)2] application was most effective for plant shoot dry weight and plant height at 60 and 120 mM salinity stress conditions. These results support the view that supplementary Mg(NO3)2 and Ca(NO3)2 application can overcome the effects of high salinity on plant growth and growth parameters under saline conditions.