Canopy volume mitigates hail damage on grapevine berries: insights on the use of ground-based LiDAR and Bayesian probabilistic analysis

Hailstorms are a relevant hazard for viticulture in Europe, with the northern regions of Italy being particularly vulnerable. The unpredictability of hailstorm events limits the possibility of extensive studies; therefore, hail damage on crops remains poorly investigated by the scientific community. An experiment with four canopy management practices was established in Northeastern Italy, and ahailstorm event occurred on 24/07/2023. Through the LiDAR monitoring of the vineyard using a mobile robotic platform a few hours before the hailstorm event we were able to map the canopy structure and relate it to the berry damage. The vineyard showd an average of 32% of berries damaged per bunch. We found that the basal part of the canopy provided shielding for the grape bunches, resulting in reduced damage. Plants with basal damage also exhibited greater canopy contraction in the basal section, confirming the protective role of the canopy. The results were analyzed with a Bayesian approach to produce robust probabilistic inference. Our study contributes to a better understanding of the dynamics of hail damage in viticulture and can be a valuable tool to better assess the risk of hail damage in vineyards.