Intergenerational priming by Trichoderma alleviates drought stress in barley

Abstract

The escalating global climate anomalies and disruption of ecological equilibrium pose profound threats to agroecosystems and crop productivity. Drought stress, a prominent consequence of climate change, exert detrimental effects on plant physiology, thereby reducing crop yield. This study explores the implementation of Trichoderma-mediated defence priming in barley under drought stress. Through a comprehensive evaluation of encompassing morphological, stomatal, biochemical, and yield parameters, Trichoderma- primed barley is compared with non-primed barley under drought stress conditions. Our results revealed that Trichoderma-primed barley exhibits heightened tolerance to drought stress in comparison to non-primed barley. The improved stomatal characteristics indicate that Trichoderma priming enables the plant to better adapt to drought conditions. Biochemical analysis showed enhanced photosynthetic pigments and reduced MDA in primed barley under drought, suggesting that primed barley experiences less oxidative stress compared to non-primed barley. Additionally, Trichoderma-primed plants displayed heightened levels of both non-enzymatic and enzymatic antioxidant activities, aiding in ROS detoxification. Stress responses are activated upon encountering a triggering stimulus (drought stress), but not after Trichoderma priming. This means there was no wasteful diversion of resources towards resistance mechanisms in the absence of stressful situations, leading to enhanced yield for primed barley compared to non-primed barley under stressful conditions. Furthermore, our investigation into the heritability of priming effects in the succeeding generation demonstrates that the progeny of primed barley retains enhanced protection akin to their primed parents. In contrast the progeny of non-primed barley exhibits greater vulnerability under water-deficit conditions. The expression of the epigenetic regulator gene HvDME was more enhanced in primed barley and its subsequent generations than in non-primed barley. This research emphasizes the potential of Trichoderma priming as a cost-effective strategy to enhance barley production amidst climate change challenges. The priming defense approach offers an intelligent plant health management solution devoid of adverse environmental or yield-related implications. This discovery holds significant promise, particularly in regions with limited water resources where crops are highly susceptible to drought stress. The findings contribute to the advancement of sustainable and climate-resilient agriculture, offering insights for practitioners and policymakers aiming to address the adverse impacts of climate change on crop production.