Antagonist activity of yeasts and lactic acid bacteria against phytopathogenic strains of economic importance in agriculture

Agriculture requires new alternatives to control pests and diseases; biological controls can be a sustainable alternative for the continued success of this sector. This study was thus carried out to identify yeasts and lactic acid bacteria that have the antagonistic capacity to control three phytopathogens as Botrytis cinerea, Lasiodiplodia theobromae and Alternaria brassicae that have caused significant economic losses in agriculture. Thirteen strains of yeast and seven strains of lactic acid bacteria (LAB) were used to measure the percentage of growth inhibition, producti on of volatile organic compounds, production of biofilms, and the production of enzymes through a completely randomized design. The yeasts Hanseniaspora opuntiae and Saccharomyces cerevisiae and the LAB Lactococcus lactis and L. brevis stood out for their antagonistic capacity to inhibit the growth of phytopathogens by 66%, 58%, 65% and 39%, respectively. Pest and disease control highly depend on chemical phytosanitary inputs with negative economic, environmental, and social effects. This study demonstrated that the yeast H. opuntiae and the LAB L. brevis have potential as biological controls and has been observed to inhibit growth by more than 39%, providing a sustainable alternative that is less harmful to the environment and human health. To guarantee their effectivity under field conditions, their individual application, consortium application, and concentration, timing, and proper application method must be considered.