Estimation of Leaf Area for Blanc Du Bois Vitis spp., Carlos Vitis rotundifolia, and Southern Home Vitis rotundifolia x Vitis vinifera Using Simple Linear Measurement

Abstract

Florida hybrid (Vitis spp.) and muscadine (V. rotundifolia Michx.) grape acreage is increasing in the south-eastern United States for the fresh market, wine production, and other diversified products. There is little research on determining leaf area in Muscadine grapes that could be used to assess canopy balance. Previous research on nondestructive methods of assessing canopy leaf area in V. vinifera L. and V. labrusca L. varieties may not apply to V. rotundifolia and Florida hybrid varieties. Thus this research sought to verify the accuracy previous non-destructive methods for V. rotundifolia and Vitis spp. varieties grown in Florida. Linear measurements were taken on fully expanded leaf of ‘Blanc Du Bois’ (Vitis spp.), ‘Carlos’ (V. rotundifolia Michx.) and ‘Southern Home’ (interspecific V. rotundifolia × V. vinifera hybrid). Maximum length and width were used to predict leaf area using linear regressions. For each cultivar, 5 linear regression equations were developed to estimate leaf area using length and width. Length and width were log transformed and an additional 3 linear equations were developed. Equations with the product of length and width had a higher coefficient of determination for all three varieties. Therefore, these equations are recommended for use when conducting non-destructive leaf area measurements of muscadine and Florida hybrid grape varieties.