Salinity is one of the most severe abiotic stresses for crop production. The present study investigates the salinityinduced modulation in growth indicators, morphology and movement of stomata, photosynthetic pigments, activity of carbonic anhydrase as well as nitrate reductase, and antioxidant systems in two varieties of chickpea (Pusa-BG5023, and Pusa-BGD72). On 20 th day of sowing, plants were treated with varying levels of NaCl (0, 50, 100, 150 and 200 mM) followed by sampling on 45 days of sowing. Recorded observations on both the varieties reveal that salt stress leads to a significant decline in growth, dry biomass, leaf area, photosynthetic pigments, protein content, stomatal behavior, cell viability, activity of nitrate reductase and carbonic anhydrase with the rise in the concentration of salt. However, quantitatively these changes were less in Pusa-BG5023 as compared to Pusa-BGD72. Furthermore, salinity-induced oxidative stress enhanced malondialdehyde content, superoxide radicals, foliar proline content, and the enzymatic activities of superoxide dismutase, catalase, and peroxidase. The variety Pusa-BGD72 was found more sensitive than Pusa-BG5023 to salt stress. Out of different graded concentrations (50, 100, 150 and 200 mM) of sodium chloride, 50 mM was least toxic, and 200 mM was most damaging. The differential behavior of these two varieties measured in terms of stomatal behavior, cell viability, photosynthetic pigments, and antioxidant defense system can be used as prospective indicators for selection of chickpea plants for salt tolerance and sensitivity.

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Globally, increasing coal-fired power production has resulted in large accumulations of coal combustion byproducts such as fly ash, widely recognized as a valuable soil ameliorant. Taking into account bakla (Vicia faba L.) in greenhouse experiments, this study aimed to assess the effects of soils amended with fly ash (FA; 0% 5%, 10%, 20%, 30%, 40% and 50%) on the plant growth characteristics and the major photosynthesis variables [(including chlorophyll content; stomatal behavior; activity of carbonic anhydrase (CA), a chloroplast-localized metalloenzyme)]; activity of nitrate reductase (NR), a rate-limiting enzyme of nitrogen metabolism; damage indicators [reactive oxygen species (ROS); and malondialdehyde (MDA), a lipid peroxidation product; and cell viability); and also to evaluate the role of defense characteristics such as proline (a nitrogenous osmolyte), and the major enzymes involved in dismutation of superoxide (superoxide dismutase, SOD); metabolism of H2O2–metabolism (catalase, CAT), and in peroxide-cleaving redox reactions (peroxidase, POX). Measurements were done at 45 days after sowing (DAS). Among the FA-proportions tested, 40 and 50% FA caused significant decreases in plant growth characteristics namely shoot length, root length, plant fresh and dry weight, and leaf area; photosynthesis variables including chlorophyll content, stomatal behavior (aperture size, shape and frequency of stomata); activity of CA and NR, and the viability of cells. These decreases in the mentioned parameters were corroborated with increases in ROS and MDA contents. However, when grown in soils amended with 5%, 10%, 20% and 30% FA, V. faba plants exhibited improvements in the mentioned parameters of growth and photosynthesis, and stomata; and cell viability; which were accompanied with the decreased contents of ROS and MDA, and coordinated increases in the activity of SOD, CAT and POX. Given the protective role of lower concentrations of FA (5%, 10%, 20% and 30%) in V. faba, these FA concentrations may be utilized as a fertilizer in sustainably improving the health and productivity of vegetable crops.