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

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.

Efficacy of the biocontrol agent Trichoderma hamatum against Lasiodiplodia theobromae on macadamia

“…We speculate that the non-volatile and/or volatile antifungal metabolites ( Figures 2 , 3 ) produced by T. hamatum may contribute to its biocontrol aptitude. The efficacy of biocontrol agents in vitro , however, does not guarantee their efficacy in planta ( Collinge et al, 2022 ). Therefore, we also assessed the biocontrol efficacy of T. hamatum against L. theobromae on potted, three-year-old, macadamia plants.…”

Biocontrol of Phytophthora xcambivora on Castanea sativa: Selection of Local Trichoderma spp. Isolates for the Management of Ink Disease

“…act as biocontrol agents implementing four different strategies to reduce the growth of the pathogen: competition for nutrients in the same growing space, antibiosis by producing secondary metabolites (diffusible and VOCs) toxic for the pathogen, mycoparasitism by the formation of coilings, and synthesis of the cell wall degrading enzyme [58][59][60]. One of the best strategies to isolate effective beneficial fungi to be used against a specific pathogen is to search/investigate around healthy plants within the outbreaks of a disease or in places where the development of the pathogen is promoted [61,62]. According to this evidence, in this study, 20 Trichoderma spp.…”

Curvularia lunataand Curvularia Leaf Spot of Maize in China

“…Biological control is receiving increasing attention as an alternative means of disease control; however, it is generally still in the experimental stage, and few BCAs are currently available for the maize production system. 111 Seed coating agents containing biocontrol microbes have shown ISR effects, reducing foliar disease infection, but their control efficiency is usually not as high as that of chemical fungicides. In addition, common environmental stress factors, such as high temperature and drought, often impact the BCA effect in fields.…”