Autophagy and stress tolerance in plants: the central role of ATG18—a review

Autophagy is an ancient, conserved system that underpins plant survival by recycling damaged organelles and nutrients under biotic and abiotic stress. This review synthesizes recent advances in three autophagic pathways in plants and the core ATG machinery that executes them. Among them, ATG18, functioning as a phosphatidylinositol 3-phosphate (PI3P) effector, is indispensable for plant survival under stress, underscoring its critical significance. By integrating biotic/abiotic signals via post-translational modifications, it dynamically regulates autophagy to clear damaged components, recycle nutrients, and enhance disease resistance. It provides a theoretical framework for elucidating plant resistance and suggests strategies such as promoter editing, allele pyramiding, and CRISPR-mediated expression tuning to exploit ATG18 for breeding crops with combined disease resistance and abiotic-stress tolerance, offering valuable perspectives for agricultural advancement.