The Cornell Grapevine Breeding Program: developing disease-resistant cultivars for more sustainable wine production

Abstract

The Cornell Grapevine Breeding Program (CGBP), based at Cornell AgriTech in Geneva, New York, develops new wine grape cultivars adapted to the northeastern United States (US) and other cool-climate regions. The program’s goal is to breed cultivars that produce exceptional wines while thriving under challenging environmental conditions. A central focus is durable resistance to major grapevine diseases, including powdery mildew, downy mildew, and black rot, combined with winter cold hardiness and superior wine quality. Growers in the northeastern US face persistent challenges from high disease pressure, variable weather patterns, and rising labor and input costs. Humid summers and proximity to the centers of origin for major grape pathogens drive some of the most intensive fungicide spray programs in the US. As climate variability and disease pressures increase, growers urgently need cultivars that combine reliable environmental adaptation, durable disease resistance, reduced input requirements, and high wine quality. To meet these needs, the CGBP integrates traditional breeding with modern genomic and phenotyping tools to accelerate the development of resilient, high-value cultivars. Strategic crosses are made among elite parents with the goal of stacking multiple resistance genes for broad, durable disease resistance. Seedlings are grown in greenhouses and screened using marker-assisted selection for key resistance loci. Selected seedlings are planted in no-spray nurseries where they are exposed to natural disease pressure and evaluated for early vigor and resistance. Surviving vines are then planted in low-spray vineyards for further evaluation. Promising selections advance to replicated vineyard trials where mature vine performance, cold hardiness, and fruit traits are evaluated across multiple seasons. The program increasingly employs digital imaging and computer-vision tools, including the Cornell-developed PhytoPatholoBot, to generate standardized high-throughput phenotyping data for disease and vine traits. Fruit from early and advanced selections is harvested, analyzed for juice chemistry, and vinified in small experimental lots. Wine quality is evaluated using instrumental analyses alongside structured sensory evaluation. A trained sensory panel, complemented by industry and consumer tastings, provides feedback on aroma, flavor, mouthfeel, and overall quality to ensure alignment with market preferences. Through this integrated breeding pipeline, the program is developing and releasing new cultivars that enable a reduction in fungicide use by up to 90%, improve grower profitability, and support sustainable cool-climate viticulture.