Phyllosphere grapevine yeast Aureobasidium pullulans reduces Aspergillus carbonarius (sour rot) incidence in wine-producing vineyards in Greece

Phyllosphere yeasts were isolated from leaves of vine (Vitis vinifera L.) canes and evaluated in a detached berry assay for their ability to suppress Aspergillus carbonarius (Order: Eurotiales, Family: Trichocomaceae) growth. Seventeen of the 21 yeast isolates significantly reduced A. carbonarius growth, i.e. sour rot infection compared to untreated controls in laboratory tests. The most effective yeast isolate Aureobasidium pullulans (Order: Dothideales, Family: Dothioraceae), isolate Y-1, was field tested on two varieties of red grape, Grenache Rouge and Agiorgitiko located on the Island of Rhodes and in Corinthos County, Greece. It was demonstrated that A. pullulans Y-1 was as effective as the commercial fungicide fludioxonil + cyprodinil, in reducing sour rot infection, A. carbonarius presence on berries at harvest and ochratoxin A contamination in must.