Tannino DC is a liquid “whole chestnut extract” obtained exclusively through physical processes, which improves plant resistance to biotic and abiotic stress. Rich in polyphenols and organic acids, it provides an anti-laccase action on ripening grapes, mild acidification of soil pH with improvement of root activity, a disruptive action against nematodes, fungi, viruses and bacteria, and exerts an antioxidant activity and a regulator of cellular and phytohormonal metabolism.