Evaluation of minimal pruning upon vine performance and berry composition of Chancellor

Own-rooted Chancellor vines were subjected over a three-year period to three pruning treatments: manually pruned, hedged, and minimally pruned. Yields of hedged and minimally pruned vines were higher than manually pruned vines, but cluster weights, berries per cluster, and berry weights were lower. Minimal pruning resulted in fruit with lowest degrees Brix, while hedged vines led to lower degrees Brix than manually pruned treatments in two of three years. Minimal pruning also resulted in lowest titratable acidity and pH in two of three seasons. Manually pruned vines had highest berry anthocyanin concentration in two of three years. These preliminary data suggest that both hedging and minimal pruning of late-season French-American hybrid varieties such as Chancellor may not be practical unless accompanied by crop thinning.