Evaluation of grape rootstocks in north Florida

• Author(s): Cousins, Peter; Lu, Jiang; Ren, Zhongbo;
• Abstract: To understand the adaptation of grape rootstocks commonly used in major grape production areas worldwide to Florida, where Pierces Disease (PD) and anthracnose are prevailing, ten grape rootstocks were evaluated at the experimental vineyard, Florida A & M University, Tallahassee, Florida, for their disease incidence and growing performance. PD and anthracnose symptoms were scored in September and October, 2002, based on the severities of leaf symptons. None of the grape rootstocks was completely resistant to PD and anthracnose, and the severity of diseases varied. Ramsey and St. George showed less PD symptoms, while Freedom and 3309C had the highest PD scores. For anthracnose disease, 5C, St. George and Freedom showed lower disease incidents, while Ramsey, 110R and O39-16 had more severe anthracnose symptoms. Vine vigor was evaluated in the fall of 2002 and varied among the rootstocks as evidenced by trunk diameter, annual shoot length, annual shoot node number, internode length and shoot diameter. Shoot death rate ranged 7% to 56%, with Freedom the highest and O39-16 the lowest.
• Publication Date: Aug 2003
• Journal: Hortscience