Blight and ink disease as constraint factors in chestnut stands of mediterranean and central Europe.

Chestnut stands located in France, Italy, Hungary, Slovenia and Slovakia were surveyed for their phytosanitary situation. Chestnut blight is the most common disease in these woods. In the past, Cryphonectria parasitica has caused severe damage both in France and Italy but spontaneous re-growth of the blighted trees is occurring in almost all the visited stands. In Slovenia, Hungary and Slovakia the disease has been spreading recently. Healing and healed cankers and hypovirulent strains of the parasite are present in many of the investigated chestnut woods and a reduction of damage was related to their spread in all the investigated countries. Several intrusive species of trees are in competition with chestnut trees in abandoned stands. Ink disease, caused mainly by Phytophthora cambivora, was observed both in France and Italy stands and its damage appears very effective and increasing. The effects of both the diseases on the evolution and development of chestnut woods are evaluated and their sustainable management is discussed.