Influence of the training system on the agronomic behavior and grape composition of Albariño in Rías Baixas appellation

Abstract

Albariño is the most important grape variety in the Rías Baixas Appellation (Galicia, Spain), and the quality of its wines is worldwide renowned. The training system most commonly used for growing Albariño is the overhead trellis, also called “parral” in Spanish. This system allows high levels of light interception, with bunches not exposed. Canopy management is not easy hence leaf density might become excessive in vigorous vineyards. The aim of this study was to evaluate the performance of Albariño cultivar when using training systems other than the parral. In the experimental vineyard Pe Redondo, Martín Códax Winery, four different training systems were subjected to study over a period of four years: Parral (P), Geneve Double Courtain (GDC), Scott-Henry (SH), and Vertical Shoot Positioning (VSP). Yield, number of bunches per shoot, bunch weight and berry weight values were determined at harvest. Different must composition parameters were also measured at harvest: pH, titratable acidity, and concentrations of sugar, malic acid, tartaric acid, free amino nitrogen, and potassium. Pruning weight was determined in winter. Bearing in mind that there were small differences in the number of shoots per square meter, GDC was the training system with the highest yield as it had the highest number of bunches per shoot and bunch weight, followed by Parral, SH and VSP. The division of the canopy -GDC and SH- contributed to vigour reduction as well as the increase of Ravaz index. Regarding berry composition, the concentration of malic acid and titratable acidity were both higher in Parral, followed by VSP, SH and GDC, due to increasing values of light exposure and higher rates of malic acid degradation. The concentration of free amino nitrogen in must decreased with vigour reduction. These results may be of help for grape growers of Rías Baixas appellation, in relation to pursued objectives on grape quality and yield, when designing new vineyards with training systems different to Parral.