The application of chitosan and benzothiadiazole in vineyard (Vitis vinifera L. cv Groppello Gentile) changes the aromatic profile and sensory attributes of wine

This work reports the effects of resistance inducers on wine aroma compounds and sensory attributes. Resistance inducers are a class of products able to elicit the plant defence mechanisms against pathogens, incurring lower toxicological risks than conventional agrochemicals. Among them, chitosan (CHT) and benzothiadiazole (BTH) are particularly effective in stimulating the biosynthesis of bioactive phytochemicals. They were used in a two-year survey conducted to assess experimental wines obtained from elicitor-treated grapes. Compared with conventional fungicides (penconazole and methyldinocap), in 2009, BTH increased total acetals and esters, while CHT raised the levels of total acetals and alcohols. Sensory analysis revealed that overall acceptance was higher in CHT than in BTH. In 2010, differences were not significant. Therefore, plant activators deserve attention beyond their efficacy in crop protection. In particular, in our experimental conditions, CHT improved the volatile profile, flavour and taste of Groppello wine.