Soybean (Glycine max L.) is an important oilseed crop but is known to be sensitive to environmental challenges. Soil salinity is known to hamper soybean growth and yield significantly. Through this investigation, we tried to uncover the important insights into physiological, biochemical, and molecular responses and adaptive strategies of two Indian soybean cultivars - MAUS-47 (salt-tolerant) and Gujosoy-2 (salt-sensitive) to salinity stress. In a completely randomized block design experiment, plants of both cultivars were subjected to control (no salt treatment) and salt treatment (100 mM NaCl) at the trifoliate stage (10 plants of each cultivar per treatment with three biological replicates). Salinity stress generated reactive oxygen species (ROS), both free and non-free-radical forms, which seemingly triggered cell death as revealed by spectrophotometric histochemical analyses with significant varietal differences. Cultivars showed differential ROS-scavenging (enzymatic/non- antioxidative machinery) capabilities. The functioning of ion-accumulating channels differed between the two cultivars, with the sensitive cultivar exhibiting a higher intake of Na+ ions, leading to the replacement of essential K+, P+, and Mg2+ ions and thus ionic imbalances. This ion imbalance could be attributed to the yield damage, growth, and developmental delays in the sensitive cultivar under salt stress conditions. The expression pattern of 5 key genes representing salt-overly-sensitive (SOS) pathways, transcription factors, and antioxidant enzymes was revealed by qRT-PCR analysis. Differential expressions were observed for the genes corresponding to Na+/H+ antiporter (SOS1), transcription factors (WRKY and MYB), nitrate reductase-1, and superoxide dismutase (Cu-Zn). These findings thus shed light on the intricate mechanisms underlying salt stress responses in soybean and how tolerant and sensitive cultivars show differential strategies, offering valuable insights for developing salt-tolerant varieties and improved agricultural practices.

Globally from abiotic stresses, salt stress is the major stress that limits crop production. One of them is wheat that has been utilized by more than 1/3 of the world population as staple food due to its nutritive value. Biochar is an activated carbon that can ameliorate the negative impacts on plants under saline conditions. The present study was conducted to examine the ameliorative impact of Biochar application to Triticum aestivum L. plant grown under salinity stress and evaluated on the basis of various growth, yield, physiological, biochemical attributes. Preliminary experiment was done to select the Triticum aestivum L. varieties with 90% germination rate for further experiment. The selected varieties, FSD08 and PUNJAB-11 of wheat were treated with two levels of sodium chloride (0 mM and 120 mM). Two varieties of wheat included FSD08 and PUNJAB-11 were treated with two levels of sodium chloride (0 mM and 120 mM). To address the impact of salt stress two levels of biochar 0% and 5% was used as exogenous application. A three way completely randomized experimentation was done in 24 pots of two wheat varieties with three replicates. The results demonstrated that salt stress affected growth, physiological attributes, yield and inorganic mineral ions (Ca2+ and K+) in roots and shoots parameters of wheat negatively while biochar overall improved the performance of plant. SOD, CAT, APX and POD activities enhanced during salt stress as the plant self-defense mechanism against salinity to minimize the damaging effect. Salt stress also significantly increased the membrane permeability, and levels of H2O2, MDA, Cl and Na ions. Biochar treatment nullified negative impacts of NaCl and improved the plant growth and yield significantly. Hence, biochar amendment can be suggested as suitable supplement for sustainable crop production under salinization.