Enhancing water use efficiency and phytochemical responses of fenugreek plants cultivated under drought stress using superabsorbent hydrogel

This study investigates the impact of two different superabsorbant hydrogels (SAH) on the growth and development of fenugreek plants cultivated under sandy soil conditions. The hydrogels used in this study were (Polyacrylic acid and Vinyl alcohol sodium polyacrylate (and were applied with rates of 0.05, 0.1, 0.2, and 0.4% of the soil weight. The amended soil with SAH could improve the growth of fenugreek plants, and the enhancement level was simultaneous with the added hydrogel rate. Morphologically, the highest concentration (0.4%) of SAH treatments recorded the highest values of plant height, root lengths, fresh weights, and shoot and root dry weight. SAH enhanced water use efficiency by modulating relative water content (RWC) in plants compared to the control. Application SAH improved transpiration rates, stomatal conductance, Water use efficiency, Photosynthesis rate, and chlorophyll contents compared to non-treated. In contrast, antioxidant enzyme activities Superoxide dismutase (SOD), peroxidase (POD), Ascorbate peroxidase (APX), Catalase (CAT), protein contents, carbohydrate content, amino acids, and proline content were decreased when SAHs were applied as the plant was still far from the wilting point. This study shows that applying SAH in newly reclaimed desert soils was advantageous for those who had suffered from water shortage conditions.