Analysis of Climatic Risk Favorability of Grapevine Fungal Disease Occurrence for Santa Teresa, Espírito Santo State, Brazil

The State of Espírito Santo, Brazil, has micro-regions with different climatic and soil conditions, which promote grapevine cultivation vine in several municipalities. However, the grape production process is strongly threatened by foliar fungal diseases, and its control increases the cost of production significantly. In turn, the use of models of prediction of disease occurrence allows the identification of regions with climatic risk potential for grapevine. Hence, the objective of this work was to analyze the agro-climatic favorability of climatic risk for occurrence of fungal diseases of downy mildew (Plasmopara viticola) and Botrytis cinerea on the grapevine for the municipality of Santa Teresa, in the state of Espírito Santo. Predictive models of favorability of downy mildew and B. cinerea were used. The number of sprayings was determined by the calendar system and by the rainfall system, according to the length of the cycle. Therefore, a series of meteorological data from 2007 to 2016 was used. The results showed that the frequency of days with low risk of mildew was 2%, medium risk 5%, high risk 93%. For B. cinerea, these values were 32%, 68%, and 0%, with low, medium and high risk, respectively. The number of required sprayings, according to the weather conditions, was lower than the number of sprayings recommended by the calendar system. The relationship between the risk of occurrence of the evaluated diseases showed a higher agro-meteorological favorability of occurrence of mildew in relation to B. cinerea.