ALLEVIATION OF SALT STRESS BY USING POTASSIUM NITRATE IN DIFFERENT GENOTYPES OF SOYBEAN (GLYCINE MAX L.)

The world is facing a biggest threat of salinity that are causing a severe reduction in crops growth and yield. In order to appraise this salinization an experiment in hydroponic was executed in the year 2022 with eleven (11) genotypes of soybean sown under the stress induced by salts. Raised nursery plants of soybean were shifted to metal tub having 200 Liters solution of Hoagland and plants were kept in solution for a period of two weeks. Treatments structure was consisted of different concentrations of NaCl alone and with mixing of both NaCl and KNO3. NaCl levels were kept 0.0 mM, 60 mM and 120 mM, respectively, while mixing of NaCl with KNO3 were kept as 60 mM sodium chloride (NaCl) with 6 mM potassium nitrate, 60 mM sodium chloride (NaCl) with 09 mM potassium nitrate (KNO3), 120 mM sodium chloride (NaCl) with 6 mM potassium nitrate (KNO3) and 120 mM sodium chloride (NaCl) with 09 mM potassium nitrate (KNO3), and these levels were distributed in each tub. A significant decrease in parameters of growth along with in ions up-taking, H2O balance and gas exchange were recorded in treatment structure. Least reduction was recorded in control treatment compared with highest reduction in 120 mM NaCl+09 mM KNO3 treatment application trailed by where only 120 mM NaCl was applied. It was found that genotypes No. 62 and No. 13 exhibited most tolerance to salts and Ajmeri and William-82 as most sensitive to salts stress. It was also noted that by using KNO3 in salt media enabled plants to alleviate the salt stress, however, best salt stress alleviation was observed at higher dose of potassium nitrate use in the growing media.