Insight into the Microbiological Control Strategies against Botrytis cinerea Using Systemic Plant Resistance Activation

Abstract

Botrytis cinerea is a polyphagous necrotrophic fungus and is the causal agent of grey mold diseases in more than 1400 different hosts. This fungus causes serious economic losses in both preharvest and post-harvest—mainly in grape, strawberry, and tomato crops—and is the second most important pathogen worldwide, to our knowledge. Beneficial bacteria and fungi are efficient biocontrol agents against B. cinerea through direct mechanisms, such as parasitism, antibiosis, and competition, but also indirectly through the activation of systemic plant resistance. The interaction between plants and these microorganisms can lead to the development of defensive responses in distant plant organs, which are highly effective against foliar, flower, and fruit pathogens, such as B. cinerea. This review aimed to explore the systemic plant defense responses against B. cinerea by compiling all cases reported (to the best of our knowledge) on the use of beneficial bacteria and fungi for agriculture, a subject not yet specifically addressed.