Blackwood Disease

Grapevine affected by blackwood disease with dried berries and chlorotic leaves

The blackwood disease (Bois noir) is on vines occurring disease caused by (Stolbur-) phytoplasma is triggered ( phytoplasma ) and the yellowing diseases in viticulture belongs. The phytoplasms are transmitted from plant to plant by phloem-sucking cicadas. The infection does not lead to the first symptoms until the following year: the infected vine wood does not mature completely in summer and dies after winter, turning black. With red grape varieties, the leaves turn red in sectors, with white grape varieties, however, light green (chlorotic); in both cases the leaves curl up at the edge. The berries ripen with a delay, become bitter and dry out.

Transmitters and Control Measures

The main carrier of blackwood disease is the leaf hoppers Hyalesthes obsoletus . The transmission of this disease has been scientifically proven in another cicada, Reptalus panzeri (rose glass winged cicada). In search of their host plants, infected cicadas can accidentally prick grapevines and thus transfer phytoplasms to the grapevine. In order to curb phytoplasmosis, the affected vines are cut back in summer and nettles are removed from the wine-growing area. Fighting nettles with glyphosate should take place outside the cicada flight phase to prevent search bites on the vines.

Blackwood disease can be confused with golden yellow yellowing .

Web links

• Blackwood disease - Rebschutzdienst northeast
• Information on blackwood disease (LVWO Weinsberg)

literature

• Jancis Robinson : The Oxford Wine Lexicon . Hallwag, Gräfe and Unzer, Munich 2006, ISBN 978-3-8338-0691-9 .
• Horst Diedrich Mohr (Hrsg.): Color atlas diseases, pests and beneficial insects on the grapevine . Eugen Ulmer, Stuttgart 2005, ISBN 3-8001-4148-5 .
• Pierre Galet : Les maladies et les parasites de la vigne . tape 1 . Imprimerie du Paysan du Midi, Montpellier 1977, ISBN 978-2-87777-038-5 .

Individual evidence

1. ↑ T. Cvrković et al .: Experimental and molecular evidence of Reptalus panzeri as a natural vector of bois noir . In: Plant Pathology , 2013, pp. 1365-3059, doi: 10.1111 / ppa.12080 .
2. ↑ lwg.bayern.de ( Memento of the original from August 18, 2009 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.