‘Blanc du Soleil’: A Wine Grape for the Southeast United States

Clusters of ‘Blanc Du Soleil’ grapes 1-year old wine col of ‘Stover’ (L), ‘Blanc du

Soleil’ (M) & ‘Blanc du Bois’ (R) Photos courtesy of FAMU

College Station, TX A team of researchers from Texas A&M University, Florida A&M University and the San Antonio Botanical Garden recently introduced ‘Blanc Du Soleil,’ a novel wine grape cultivar tailored specifically for the unique climatic conditions of the Southeast United States. The cultivar is well suited for warm grape-growing regions such as Florida, Texas, and the Southeastern United States. It can produce a high-quality wine with varietal character and satisfactory yield. It is the first cooperative release with Texas A&M University.

Florida and the southern grape industry have always been challenged by the prevalence of Pierce’s disease (PD). Previously, the production of bunches of grapes in the area has solely been based on a few hybrid grapes that could adapt to the region’s hot-humid climate and be tolerant or resistant to PD. Engineered to withstand the region’s high humidity, intense heat, and disease pressures, this cultivar offers vintners a reliable and sustainable option for producing premium-quality wines.

Unlike traditional grape varieties, which often struggle to adapt to the Southeast’s climate, ‘Blanc Du Soleil’ demonstrates exceptional resilience and vigor, ensuring consistent yields and superior fruit quality. Its ability to thrive in warm, humid conditions makes it an ideal choice for vineyards across the Southeast, from North Carolina to Florida..

The clusters of ‘Blanc Du Soleil’ are medium-sized, often shouldered, and cylindrical. Cluster weights in Goliad ranged from 79.44 to 106.46 g. In Florida, cluster weights were larger averaging 168.8 to 235.1 g. ‘Blanc Du Soleil’ clusters are moderately to well filled with medium-sized, light green- to bright yellow-colored berries. Berry weights averaged 1.97 g in Industry, 1.84 g in Goliad, and 2.90 g in Tallahassee.

Wine pH was lower and titratable acidity was higher for ‘Blanc Du Soleil’ at both locations in Texas, which may be valuable for warm climate regions where high pH may result in problems with wine stability. Wine pH and titratable acidity of ‘Blanc Du Soleil’ ranged from 3.09 to 3.20 and 6.8 to 8.9 g/L, respectively, in Texas. In Florida, wine pH ranged from 3.06 to 3.22 and titratable acidity ranged from 8.2 to 9.8 g/L.

The most valuable characteristic of ‘Blanc Du Soleil’ is its survival capacity and high fruit and wine quality potential in the Gulf Coast, a region of the United States that has extreme pressure from PD. Although formal testing for PD tolerance has not occurred, its survival and lack of symptoms for 23 years suggests tolerance or some level of resistance. Vine survival at all sites was 100% over the course of evaluation. Furthermore, both parents of ‘Blanc Du Soleil’ are tolerant to PD.

‘Blanc Du Soleil’ is a promising white wine grape variety suitable for cultivation in the southern United States. It boasts high-quality potential and strong resistance to diseases, particularly Pierce’s Disease (PD), which is a significant concern for grape growers in the region. Its disease resistance makes it a valuable option for areas prone to PD, offering both quality and reliability to growers.

Justin Scheiner is an Associate Professor and Extension Viticulture Specialist at Texas A&M University and the Texas A&M AgriLife Extension Service. His research program focuses on best management practices for vineyards in Texas including practices to improve fruit and wine quality, rootstocks and new grape cultivars, cover cropping and soil health, and irrigation management. He is a member of the graduate faculty at Texas A&M and teaches courses in the Department of Horticultural Sciences.

Dr. Violeta Tsolova is a Professor and Director of the Center for Viticulture and Small Fruit Research, College of Agriculture and Food Sciences, Florida A&M

The full article can be found on the ASHS HortScience electronic journal website at: https://doi.org/10.21273/HORTSCI17032-22

Established in 1903, the American Society for Horticultural Science is recognized around the world as one of the most respected and influential professional societies for horticultural scientists. ASHS is committed to promoting and encouraging national and international interest in scientific research and education in all branches of horticulture.

With thousands of members worldwide, ASHS represents a broad cross-section of the horticultural community-scientists, educators, students, landscape and turf managers, government, extension agents and industry professionals. ASHS members focus on practices and problems in horticulture: breeding, propagation, production and management, harvesting, handling and storage, processing, marketing and use of horticultural plants and products. To learn more, visit ashs.org

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