Polyphenol Oxidase Activity during Rooting in Cuttings of Grape (Vitis vinifera L.) Varieties

Polyphenol oxidase (PPO) activity was investigated during rooting in cuttings from three different grape cultivars (Vitis vinifera L. cvs. Muscat, Cardinal and Perlelte), and the enzyme activity and rooting ability were compared. Rooting was observed on the Muscat and Perlelte cuttings, but not on the Cardinal cuttings. PPO activity started to increase in the early stage of the experiment, and decreased after root emergence in the Muscat and Perlelte cuttings. However, enzyme activity started to increase in the early stages and continued throughout the experiment in the Cardinal cuttings. No apparent correlation was found between PPO activity and rooting ability in the cutting.