GhPsbO breaks the growth-immunity trade-off by simultaneously promoting growth and defence in cotton

Abstract The evolutionarily conserved trade-off between pathogen resistance and crop yield remains a major bottleneck in agricultural breeding. Although numerous genes governing disease resistance or growth productivity have been identified, the pleiotropic regulatory factors that harmonize these two agronomic traits remain largely elusive. Here, we report that the cotton (Gossypium hirsutum) chloroplast oxygen-evolving complex protein GhPsbO is dually modulated at both translational and transcriptional levels by the Verticillium dahliae effector Vd10375. Overexpression of GhPsbO enhances photosynthesis and accelerates lignin deposition to establish structural defense, thereby simultaneously improving crop yield and disease resistance in cotton. Unexpectedly, knockout of GhPsbO enhanced resistance to V. dahliae by elevating chloroplast-derived reactive oxygen accumulation and result in plant sacrifices. Consistently, transcriptional repression of GhPsbO by overexpression of the transcription factor GhMYB44 significantly improved cotton resistance, mirroring the GhPsbO knockout disease-resistant phenotype. Collectively, our findings uncover a regulatory module balancing plant growth and immunity, and provide a promising molecular strategy for breaking the growth-defense trade-off to achieve sustainable crop production.