Abstract
Green gram (Vigna radiata), also known as Mung bean, belongs to the Fabaceae family. Environmental stress, particularly salinity, significantly limits plant growth and productivity. Plant growth regulators (PGRs), such as NAA, kinetin, and gibberellic acid, can mitigate the effects of salinity stress. A study was conducted from April to July 2022 at the Crop Physiology Laboratory, Thanthai Roever Institute of Agriculture and Rural Development, Perambalur, Tamil Nadu, India, to examine the “Effect of plant growth regulators on green gram (CO 8) under salinity stress.” The experiment aimed to standardize NaCl levels for assessing salinity effects on seed germination and to evaluate PGR responses under salinity stress. NaCl concentrations of 75 mM, 100 mM, 150 mM, and 200 mM were tested, with 50% germination observed at 150 mM, which was standardized for subsequent trials. The study followed a Completely Randomized Design (CRD) with eight treatments: T1 (Absolute Control), T2 (150 mM NaCl), T3 (NAA 100 ppm), T4 (NAA 200 ppm), T5 (Kinetin 50 ppm), T6 (Kinetin 100 ppm), T7 (GA₃ 100 ppm), and T8 (GA₃ 200 ppm). Results showed that salinity stress reduced seedling growth, but PGR treatment improved germination, shoot and root length, dry matter production, vigour index, Stress tolerance index (%), Relative water content (%), Chlorophyll a (mg g-1), Chlorophyll b (mg g-1) & Total Chlorophyll content (mg g-1). GA3 200 ppm (T8) exhibited the highest germination (79.68 %), shoot length (17.3 cm), root length (6.4 cm), vigour index (1745), dry matter production (0.25 g), Stress tolerance index (83.09 %), Relative water content (88.44 %), Chlorophyll a (0.95 mg g-1), Chlorophyll b (0.21 mg g-1) & Total Chlorophyll content (1.22 mg g-1) demonstrating its effectiveness in mitigating salinity-induced stress.