Biological control of plant diseases – What has been achieved and what is the direction?

TLDR

The global sustainability agenda drives a need to reduce agricultural inputs while maintaining yield, yet plant diseases remain a major constraint, and although biological control agents have been developed and marketed worldwide, they are often niche products with limited applications. The review synthesizes intensive research on developing new biological control agents and elucidating their mechanisms, drawing on input from a 300‑participant British Society for Plant Pathology webinar and its co‑author panel. Biological control agents show promising prospects, supplementing other sustainable practices and offering solutions for diseases where conventional methods fail, with increasing use expected to benefit the environment.

Abstract

Abstract The global sustainability agenda is increasing the demand for reduction in inputs into agricultural production while maintaining profitable yield of quality products. Plant diseases are a major constraint for both yield and product quality, but often tools for their control are ineffective or lacking. Biological control using antagonistic microorganisms has long been a subject of research resulting in a wide range of products that are now available and marketed in specific territories around the world. These preparations are often niche products with narrow uses. The research effort is intense both to develop new biological control agents (BCAs) and to obtain knowledge of the mechanisms underlying biological disease control. The prospects for biological control are promising. As a minimum, BCAs supplement other sustainable disease management practices such as disease resistance, and present opportunities for controlling diseases for which other approaches are ineffective or unavailable. We can realistically expect increasing use of BCAs to control crop diseases in ways that will benefit the environment. This review paper arose from a webinar held by the British Society for Plant Pathology as part of the International Year of Plant Heath (IYPH2020), at which many of the 300 participants posed or discussed interesting questions. This review is based on that input and the panel members at the webinar are all included as co‐authors in this review.