Ethylene-Mediated Regulation of Wheat ( <i>Triticum Aestivum</i> ) Physiology in Association with <i>Trichoderma Spp.</i> Under Lead-Induced Heavy Metal Stress

Heavy metal accumulation, particularly lead, poses a significant threat to agricultural productivity and food safety, necessitating effective amelioration strategies. The non-degradable nature of lead ensures its persistence in soil and water, leading to long-term environmental and health risks through bioaccumulation in the food chain. Triticum aestivum, a vital global crop, is highly susceptible to lead stress. Lead toxicity severely disrupts plant physiological and biochemical processes, including reduced photosynthetic rates, altered stomatal conductance, decreased nutrient uptake, and impaired seed germination, ultimately leading to significant yield losses. This stress often induces oxidative damage through reactive oxygen species overproduction. Phytohormones like ethylene are crucial regulators of plant responses to abiotic stress, influencing photosynthetic efficiency and antioxidant systems. Ethylene production can be enhanced under metal stress, and its signaling pathways are implicated in plant adaptation and tolerance to toxic metals. Simultaneously, beneficial fungi such as Trichoderma spp . are known for their plant growth-promoting abilities and stress mitigation. Trichoderma can modulate plant hormone pathways, including ethylene, and some species produce ACC (1-Aminocyclopropane-1-carboxylic acid) deaminase, which reduces ethylene levels, thereby enhancing plant tolerance and root development. This research investigates the synergistic interactions of exogenously applied ethylene and Trichoderma spp . on wheat’s physiological and biochemical responses under lead stress. We hypothesize that while lead stress will severely disrupt photosynthetic proficiency and increase oxidative damage, both ethylene and Trichoderma will individually enhance stress resistance. Their co-application is predicted to synergistically boost photosynthesis, enhance antioxidant defense mechanisms, and decrease lead accumulation, offering an eco-friendly approach to alleviate heavy metal stress in wheat.