Incidence of fungals in a vineyard of the denomination of origin ribeiro (Ourense - north-western Spain)

Abstract

Knowledge about the fungal spores most abundant in the atmosphere of a vineyard is of great use since it allows development of prediction models of the spore concentration, and therefore application of phytosanitary treatments only when high levels of fungal propaguls are detected. In this study the concentration of phytopathogenic spores is related with the different phenological stages of the vineyard, and a prediction model developed for each fungal type using meteorological, phenological and spore concentrations variables. The study was carried out in a vineyard of the Ribeiro district during the year 2007. For the aerobiological study a volumetric Hirst type trap was used, while phenological observations were carried out on 20 plants of the three varieties monitored (Treixadura, Godello and Loureira) following the phenological scale standardized by the BBCH. Botrytis reached the highest annual total value with 16,145 spores, followed by Plasmopara with 747 spores and Uncinula with 578 spores. In order to forecast the concentration of the phytopathogenic fungal spores, equations of lineal regression were elaborated including as estimators, variables with high correlation coefficient. For Botrytis the regression equation explained 42.4% of the variability of spore concentration, 26.1% for Uncinula and 24.7% for Plasmopara