Vineyard Management and Physicochemical Parameters of Soil Affect Native Populations, Sources of Biocontrol Agents against .

Native strains of in vineyard soil represent an opportunity for reducing the incidence of grapevine trunk diseases (GTDs) in vineyards. Moreover, its relationship with the environment (physicochemical soil characteristics and farming management practices) remains unclear. In the current study, a survey was carried out on farming management used by viticulturists, and soil samples were studied to analyze their physicochemical properties and to isolate strains. Later, statistical analyses were performed to identify possible correlations between populations, soil management and soil characteristics. In addition, tests, including antibiosis and mycoparasitism, were performed to select those strains able to antagonize . In this study a positive correlation was found between the iron content and pH in the soil, and a lower pH increases populations in soils. Vineyard management also affects populations in the soil, negatively in the case of fertilization and tillage and positively in the case of herbicide spraying. Two native strains were selected as potential biocontrol agents ( T065 and T087) using antibiosis and mycoparasitism as mechanisms of action. These results led to the conclusion that native strains hold great potential as biological control agents and as producers of secondary metabolites.