Sarah Lowder, University of Georgia Extension viticulture specialist and assistant professor in the College of Agricultural and Environmental Sciences’ horticulture department, spoke with AgNet Specialty Crop Grower about identifying Pierce’s disease in vineyards.
“Generally, the first symptom to show up is marginal necrosis on the leaves. In red varieties, that tends to have more of a red border, but in white varieties it won’t be as red, obviously. Marginal necrosis is the first symptom,” Lowder said.
Similar symptoms of other issues may also occur, such as nutrition imbalance, viruses or crown gall. UGA Extension agents can test to determine if PD is the issue.
“If you suspect PD or just want a second set of eyes on a problem vine, give your county agent a call or shoot them an email. Early identification helps not just your vineyard, but the whole region’s long-term vine health,” Lowder said.