Role of natural terroir attributes on Barbera grapevine performance and grape quality in Piemonte region (Italy)

Abstract

The trial was carried out in the Bersano estate (Nizza Monferrato, Piemonte, Italy) in different vineyards (Generala, Cremosina and Monteolivo) devoted to the production of DOCG Nizza, the newest and highly reputed Barbera denomination. For Bersano, this research provided access to scientific information and tools to valorise its Nizza wines and to characterize and select some sub-zones. The study investigated the effect of natural terroir attributes on vine behaviour and grape composition of cv. Barbera. Conducted in 2017, the tests included phenological phases, vegetative growth, chlorophyll and gas exchange measures. Maturation curves were also developed to better understand the time course of berry ripening, from fruit-set to harvest and statistical relationships were studied. The vineyards presented different climatic and soil conditions which influenced bud burst, shoot growth and plant photosynthesis; concerning soil properties, texture was the main differentiating factor. During the growing season, the berries followed the normal growth pattern, but an extreme drop occurred at harvest due to high diurnal temperatures. Ripening curves showed dissimilarities between the three studied vineyards, i.e. TSS, berry mass, total anthocyanins and total phenols. La Generala presented the best viticulture features regarding the vine performance and grape composition.