Abstract
The interaction between plants and pathogens represents a complex evolutionary arms race. Plants employ a sophisticated innate immune system to combat pathogen invasion. However, pathogens inhibit plant immunity by secreting effectors into the host cell. The chloroplast is an indispensable organelle for photosynthesis and metabolism in plants. Notably, increasing evidence has recently revealed the pivotal role of chloroplasts in plant immunity, including reactive oxygen species production, phytohormone biosynthesis, and signal transduction. Accordingly, chloroplasts have emerged as key targets for pathogen effectors. In this review, we summarize the role of chloroplasts in plant immunity and update the identification of pathogen effectors that enhance pathogenicity by targeting chloroplasts. We also discuss the diverse mechanisms by which pathogen effectors hijack chloroplasts to manipulate plant immunity, shedding light on the functional complexity and importance of chloroplasts in plant-pathogen interactions.