Defense strategies for plant health: Disease resistance and tolerance

Emerging and reemerging infectious diseases pose a major threat to wild plants and domesticated crops, a challenge intensified by increasing climate extremes and the rapid evolution of pathogen populations. To mitigate damage during pathogen-plant interactions, plants have evolved sophisticated defense strategies. Resistance, a well-established mechanism, enables plants to expel, contain, or kill invading pathogens. However, evidence from crop breeding and evolutionary studies highlights disease tolerance as an equally critical yet often overlooked strategy-where plants stay healthy despite infection, not through restricting pathogen proliferation. Unlike resistance, tolerance may not impose strong selective pressure on pathogen populations, making it a more durable solution to disease management. This review examines the impact of infectious diseases on plant health and explores how resistance and tolerance mitigate disease-induced damage. We also discuss recent advances in uncovering the molecular, cellular, and genetic foundations of disease tolerance, including mechanisms such as clearing harmful protein condensates, activating autophagy, allocating resources, and altering life history traits. Furthermore, we explore how these insights can inform the development of disease-tolerant crops through breeding and biotechnology, ultimately supporting sustainable agriculture and enhancing global food security.