Abstract
Plants combat drought and water stress by various means of which osmoregulation is most pronounced. The objective of this study was to evaluate effect water stress levels and Bacillus simplex on biochemical and enzymatic response of maize. The aim of this study was to investigate how different water stress levels, combined with Bacillus simplex inoculation, influence the biochemical and enzymatic responses of maize under controlled conditions. Specifically, the study sought to determine the extent to which bacterial inoculation mitigates the adverse effects of drought stress and enhances the production of key stress-related metabolites and antioxidant enzymes across varying irrigation regimes. An experiment was conducted to evaluate the effect of stress levels (25% irrigation), intermediate stress (50% irrigation), moderate stress (75% irrigation) and no stress (100% irrigation) and Bacillus spp. (B-/B+) on biochemical changes of maize under control conditions. Among stress levels, plants subjected to severe water stress conditions resulted in production maximum total flavonoid content, total phenolic content, total antiradical content, proline content and enzyme synthesis viz. catalase and peroxidase dismutase. Bacteria inoculation performed best in alleviating stress condition despite of water deficit conditions in all treatments of stress levels. The correlation coefficient was 0.844 between catalase (CAT) and proline content, indicating a positive correlation, and the CAT was strongly correlated with relative damage rate, total flavonoid content, total phenolic content, total antiradical capacity and peroxidase dismutase activity with correlation coefficient closer to 1. It can be endorsed from the outcomes that, the effect of severe water stress was more significant in producing biochemical compounds and enzyme synthesis and Bacillus spp. inoculated plants thrive best in combating stress under all stress levels.