Microbiota-mediated disease resistance in plants.

TL;DR: Here, the state of this cross-disciplinary field is synthesized to bridge the gap toward rational design of synthetic microbial communities (SynComs) with broad, durable, and flexible plant protective activities.

Abstract: Plant pathogens represent a constant and major threat to global food production, with 20%– 30% global crop losses estimated, principally in food-deficit areas [1]. Pesticide use, breeding of resistance genes, and genetic manipulation of plant immune components have helped to mitigate this threat. However, rapid evolution of pathogen resistance and virulence, together with host range expansion and host jumps, contribute to severe disease outbreaks, especially in the context of current agricultural practices [2]. This underscores the need to reduce the lag time between the appearance of new diseases and development of protective measures effective on a broad range of pathogens and host plants. In this context, microbial products and inoculants for plant protection have recently gained attention thanks to the large efforts made to systematically isolate, identify, and characterize plant-associated microbes that engage in intimate association with healthy plants [3]. Recent findings indicate that individualand community-level features provided by plant microbiota members can confer extended immune functions to the plant host. Importantly, the traits lent by “beneficial” microbes strongly depend on the interplay between the soil nutrient status and the plant immune system [4, 5]. Thus, the successful implementation of microbiota-mediated disease protection will depend on our mechanistic understanding of how microorganisms interact with their hosts and with one another in natural environments. Here, we seek to synthesize the state of this cross-disciplinary field to bridge the gap toward rational design of synthetic microbial communities (SynComs) [6] with broad, durable, and flexible plant protective activities.