Eutypa dieback

Eutypa dieback, associated with the pathogen Eutypa scabrosa, is a serious wood disease affecting grapevines globally. This fungus is a systemic pathogen that infiltrates the vascular system, causing permanent damage to the structural integrity and longevity of the vines.

The primary host for this pathogen is the grapevine (Vitis vinifera). While the fungus can inhabit other woody species, the agricultural impact is most severe in commercial vineyards, where it causes significant economic losses due to the premature decline of productive vines.

Symptoms become visible during the growing season as stunted, chlorotic shoots with shortened internodes. The leaves are typically stunted and display marginal necrosis or chlorosis. A cross-section of an infected trunk or cordon often reveals a dark, wedge-shaped lesion of necrotic wood.

Disease progression is highly dependent on environmental factors, particularly rainfall and temperature, which facilitate the release and dispersal of ascospores. These spores enter the vine primarily through fresh pruning wounds, making management during the dormancy period crucial.

Management of Eutypa dieback relies on preventive horticultural practices. Key strategies include pruning during dry periods, applying protective fungicides or wound sealants immediately after cuts, and removing severely infected wood to reduce the local inoculum load within the vineyard environment.