Isoenzymatic Polymorphism Differentiation of Portuguese Grapevine Cultivars

Abstract

The isoenzymatic activity of α-esterase (EC 3.1.1.1), acid phosphatase (EC 3.1.3.2), glucosephosphate isomerase (EC 5.3.1.9) and phosphoglucomutase (EC 2.7.5.1) was studied in young leaves, obtained from cuttings developed in a room with controlled environment. The zymograms of 29 grapevine cultivars grown in Portugal and some of their synonyms were analyzed, in order to authenticate synonymous names. The data analysis was performed by a numerical taxonomic method. We detected 24 polymorphic bands, which enabled the differentiation of 29 grapevine cultivars, using the four isoenzymatic systems. The principal area of application of this methodology is the resolution and confirmation of difficult cases of synonyms or homonyms in ampelography. In this study, we confirmed that Pedernã from Vinhos Verdes is a synonym for Arinto from Bucelas; Maria Gomes from Bairrada for Fernão Pires from Ribatejo; Periquita from Setúbal for João de Santarém from Oeste and for Trincadeira from Bairrada; Trincadeira Preta from Ribatejo for Crato Preto from the Algarve and for Tinta Amarela from Douro. We also concluded that Trincadeira Preta from Ribatejo is different from the homonymous Trincadeira from Bairrada.