Soil Yeasts from Sugarcane Agroecosystems: Nutrient Cycling and Biocontrol Potential in Agricultural Systems

Soil yeasts represent a significant component of the agricultural microbiota and possess high ecological and biotechnological potential in production systems such as those for sugarcane. This review analyses the importance of these microorganisms in fundamental processes related to soil health and functionality, highlighting their role in nutrient cycling, the decomposition of organic matter, and the availability of essential elements for plant uptake. Numerous studies have shown that certain yeasts possess plant-growth-promoting characteristics, including the production of phytohormones, siderophores and compounds capable of solubilizing nutrients, thereby promoting plant development and the sustainability of the agroecosystem. Furthermore, this review highlights the potential of yeasts as agents for the biological control of agricultural diseases and pests. Various mechanisms of action are described, including the production of volatile organic compounds, hydrolytic enzymes, antagonistic toxins, competition for nutrients and space, and the induction of defense responses in plants. In sugarcane systems, some yeast species such as Metschnikowia spp., Meyerozyma guilliermondii, Wickerhamomyces anomalus, Pichia spp., and Rhodotorula glutinis have demonstrated antagonistic activity against plant pathogens and the potential to be integrated into sustainable agricultural management strategies.