秋田県の生食用ブドウにおけるつる割細菌病の発生

抄録

A bacterial disease was found on the leaves, petioles and shoots of grapevine（Vitis vinifera cvs. ‘Neo Muscat’and ‘Rosario Rosso’）in Akita Prefecture in 2012. This disease was characterized by the formation of many small-spots of discoloration on leaves, and necrotic cracks on petioles and shoots. These symptoms closely resembled those of the bacterial blight of grapevine caused by Xylophilus ampelinus. The biochemical and physiological properties of the bacterial isolates obtained from affected leaves were similar to those of X. ampelinus. The 16S rRNA gene sequences of the bacterial isolates showed 99.5% similarity to the type strain of X. ampelinus ATCC 33914. Bacterial strains also showed pathogenicity on grapevine saplings. Although the first outbreak of this disease was reported on wine grapes in Hokkaido in 2011 and the outbreak in Akita Prefecture was the second instance in Japan, it was confirmed, for the first time, that this disease damaged Japanese cultivars of table grapes.