Proteomic and Hormonal Insights into Drought Stress Mitigation in Swietenia macrophylla:  Role of Jasmonic Acid and Salicylic Acid in Enhancing Resilience

Drought stress is a critical abiotic factor limiting plant growth and productivity, particularly in tropical forestry species such as Swietenia macrophylla . This study investigates the physiological, biochemical, and proteomic mechanisms underlying drought tolerance in mahogany seedlings and evaluates the efficacy of Jasmonic Acid (JA) and Salicylic Acid (SA) as mitigative treatments. Drought stress caused significant reductions in photosynthesis (Pn), stomatal conductance (Gs), transpiration rate (Tr), pigment contents, and relative water content (RWC), while inducing proline accumulation and altering protein expression patterns. Hormonal treatments markedly improved recovery, with JA demonstrating superior efficacy in restoring Pn, Gs, Tr, RWC, and pigment contents compared to SA. Proteomic analysis revealed drought-induced shifts in protein expression, with increased levels of defense-related proteins, such as heat shock protein 90 (HSP90) and sulfiredoxin, and reduced expression of metabolic and photosynthetic proteins, including RuBISCO and DAHP synthase. Recovery with hormonal treatments significantly enhanced the expression of photosynthetic and stress-responsive proteins, highlighting the complementary roles of JA and SA in mitigating stress. Gene Ontology (GO) and KEGG pathway analyses emphasized the importance of photosynthesis, metabolic reprogramming, and ROS scavenging as key adaptive mechanisms.These findings underscore the potential of JA and SA in enhancing drought resilience and provide valuable insights into the mechanisms underlying stress adaptation. This study establishes a foundation for utilizing hormonal treatments to improve the resilience and productivity of tropical forestry species under adverse environmental conditions.