Interplay of phytohormone signaling with aluminum and drought-stress resistance mechanisms: An integrated perspective amidst climate change

In recent years, the combined stress of drought and aluminum (Al) has received considerable attention due to the widespread distribution of acidic soils worldwide, exacerbated by climate change. The responses of plants to drought and Al stress are intricately governed by phytohormones, which serve as key regulators for a range of resistance mechanisms. However, the role of combined drought-Al stress remains largely unexplored. Therefore, it is important to critically examine the most recent advances in plant resistance mechanisms to combined drought and Al stress, with a specific focus on the potential involvement of phytohormonal mechanisms. It is postulated that phytohormones such as abscisic acid, auxins, cytokinins, gibberellins, brassinosteroids, and jasmonates are also involved in triggering the activation of resistance mechanisms against combined drought-Al stress, such as induction of stomatal closure, increased exudation of organic acids, and increased antioxidant activity. This review aims to deepen our understanding of the intricate interplay between phytohormonal signaling, combined Al-drought stress, and the implications of climate change. By shedding light on the underlying mechanisms that govern how plants respond to these combined stresses, we aim to pave the way for targeted strategies to mitigate the adverse effects of climate change on plant performance.