Valutazione di un modello matematico per la muffa grigia della vite

Recently, a mechanistic model based on the life cycle of Botrytis cinerea was developed. This model considers weather conditions, vine growth stages and the main infection pathways. In this study, the model was validated in nine epidemics observed from 2015 to 2017, in three locations in Italy. At maturity, no botrytis bunch rot symptoms were observed in vineyards; however, shelf-life assays showed the presence of latent infections in mature berries, with max 13% disease severity. The infection severity assessed after shelf-life assays was used to classify the epidemics as: severe, intermediate and mild (observed severity). Epidemics were classified in these three group also based on the model output (predicted severity). The model correctly evaluated the 89% of the epidemics. The severity of epidemics was also compared to the control strategies adopted by grapevine growers; it was outlined that growers taken right decision in 33% of cases only. Therefore, the model could be used as a tool supporting decision-making for Botrytis bunch rot control; it predicts the infection risk during the main susceptible vine growth stages: i. flowering (BBCH 69); ii. pre- bunch closure (BBCH 77); iii. veraison (BBCH 83); iv. pre-harvest (BBCH < 89).