The pathogen causing this vine disease is the Middle Eastern bacterium Xylophilus ampelinus (formerly Xanthomonas ampelina). It is one of the many species of protobacteria known to cause many plant diseases. The present one is specialized in vines of the species Vitis vinifera. The symptoms usually manifest themselves on shoots and stems after 3 to 4 weeks and on leaves after 10 to 14 days. They initially appear as reddish-brown streaks before they lead to cracks in the wood structure and necrotic tissue. Then the shoots wilt and dry out before they finally die. If infected before flowering, they typically develop a black colour before dying and falling to the ground. Root symptoms are rare. The bacterium prefers humid and wet conditions. So far, there have been occurrences in Greece, France, Germany, Turkey and in areas of South Africa.
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