Feasibility of Growing Pierce’s Disease Tolerant American and French-American Hybrid Bunch Grape Cultivars and Advanced Grape Selections in Alabama

Abstract

Eleven Pierce’s Disease (PD) tolerant American and French-American hybrid bunch grape cultivars including ‘Black Spanish’, ‘Blanc du Bois’, ‘Champanel’, ‘Conquistador’, ‘Cynthiana’, ‘Favorite’, ‘Lake Emerald’, ‘Stover’, ‘Villard Blanc’, ‘Seyval Blanc’ and ‘Seyval Blanc’ grafted on Coudrec 3309 rootstock (‘Seyval Blanc’/3309C) were planted at the Sand Mountain Research and Extension Center (SMREC) in Crossville, AL in 2008 to study the feasibility of growing PD tolerant hybrid bunch grape cultivars in the Alabama environment. Our results indicate that ‘Champanel’ had the most vigorous vegetative growth, while ‘Seyval Blanc’ had the weakest. ‘Stover’ had the earliest shoot development, while ‘Champanel’ and ‘Cynthiana’ had the latest. ‘Stover’ and ‘Seyval Blanc’ flowered earliest, while ‘Cynthiana’ and ‘Lake Emerald’ flowered late in the season. ‘Seyval Blanc’ and ‘Seyval Blanc’/3309C had the earliest fruit maturity, while ‘Lake Emerald’ matured late. ‘Villard Blanc’ produced the largest yield of 12.7 kg/vine and had the largest mean cluster weight of 287.1 g in 2011 and 2012. ‘Champanel’ produced the largest berries of 4.8 g. ‘Cynthiana’ and ‘Lake Emerald’ had the highest soluble solids content (SSC) with 19.8% and 18.8%, respectively, while ‘Champanel’ had the SSC of 13.1% at harvest. ‘Blanc du Bois’ and ‘Stover’ had the highest pH of 3.58 and 3.49, respectively. There were no significant differences in titratable acidity (TA) among cultivars tested which ranged from 0.56 to 1.36 g/100 ml. ‘Villard Blanc’, ‘Cynthiana’, and ‘Black Spanish’ were the best performing cultivars combining vigorous vegetative growth, high yields, and good fruit quality at the SMREC in the two study years. Three recently released seedless table grape cultivars from the University of Arkansas breeding program, ‘Faith’ (‘A2412’), ‘Joy’ (‘A2494’), and ‘Gratitude’ (‘A2505’); eight advanced grape selections ‘A2817’, ‘A2245’, ‘A2359’, ‘A2467’, ‘A2574’, ‘A2602’, ‘A2632’, and ‘A2786’; two previously released seedless cultivars ‘Mars’, and ‘Neptune’, as well as two standard cultivars ‘Conquistador’, and ‘Stover’, were planted at the North Alabama Horticultural Research Center (NAHRC) in Cullman, AL in 2008 to study the feasibility of growing advanced table and processing grape selections in Alabama environment. Vegetative growth, cropping potential and fruit quality of the tested cultivars and selections were evaluated during the 2011 and 2012 seasons. Our results indicate that ‘Joy’ had the most vigorous vegetative growth, while ‘A2786’ had the weakest. ‘Stover’ had the earliest shoot and flower development in both seasons. Selection ‘A2359’ had the greatest number of clusters per shoot. ‘Mars’ and ‘Faith’ were early ripening and maturing, while ‘Conquistador’ developed late in the season. The highest yielding selections and cultivars in our study were ‘A2574’, ‘A2359’, ‘Neptune’, ‘A2245’, and ‘Conquistador’, which produced over 12.0 kg/vine in both seasons. Table grape cultivars ‘Gratitude’ and ‘Neptune’ had the largest average cluster size of 490 g. ‘Gratitude’ and selection ‘A2817’ produced the largest berries. ‘A2632’, ‘Stover’, ‘Faith’, and ‘Joy’ had high SSC at harvest, while ‘Conquistador’ had relatively low sugar content. Selection ‘A2467’ had the highest TA of 1.34 g/100 ml. The remaining cultivars and selections had TA levels ranging from 0.52 to 0.79 g/100 ml. Selection ‘A2817’ had the largest number of seed traces (3.2), while ‘Gratitude’ had the fewest seed traces. ‘Neptune’, ‘Gratitude’, and ‘A2817’ performed best at NAHRC during study due to their superior cropping potential, fruit quality, and combined vegetative growth.