Evaluation of the ameliorative role of soil amendments and selenium on morphophysiological traits, oxidative stress, and quality attributes of wheat (Triticum aestivum L.) under varying drought stress conditions

A pot study was conducted to evaluate the ameliorative role of compost, vermicompost, and selenium spray on morphophysiological growth, oxidative stress indicators, antioxidant enzymes and yield attributes of wheat (Triticum aestivum L.) under variable drought conditions [no drought (D₀), moderate drought (D₁) and severe drought (D₃)]. Results depicted that drought stress markedly disrupted morphological growth, biomass production and yield parameters of wheat exposed to varying levels of drought. However, application of different soil amendments and selenium spray, alone and in combination, positively minimized the injurious effects of drought stress on wheat. Among various treatments, the combined application of vermicompost in soil and selenium (Na₂SeO₃) foliar spray (T₅) showed more promising results at all levels of drought stress. Maximum increase in growth parameters including plant height (11.83 %), leaf area (19.14 %), and number of tillers (9.35 %) of wheat was found in combined treatment of vermicompost and Na₂SeO₃ (T₅). Likewise, total chlorophyll, carotenoids, soluble proteins also showed significant increment by applying vermicompost and Na₂SeO₃ together. Combined application of vermicompost and Na₂SeO₃ (T₅) also reduced malondialdehyde (MDA), hydrogen peroxide (H₂O₂) and superoxide anion (O₂¯) levels by 46.5–48.2 %, 49.1–58.9 % and 20–30 %, respectively, in wheat exposed to varying drought stress. Antioxidant enzyme activities i.e., superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) were also increased in T₅ by 110.7–489 %, 54.5–152.7 %, 84.2–220.2 % and 26.01–534.2 %, respectively, in wheat plant under varying drought levels. Combined use of vermicompost and Na₂SeO₃ also positively affected the yield traits and enhanced flour yield by 5.56–6.03 % in wheat plants exposed to varying drought stress.