Budburst prediction models for the Cabernet Sauvignon grapevine cultivar in the Serra Gaúcha region, in Rio Grande do Sul, Brazil

Abstract

The objective of this article was to study different mathematical models to characterize thermal availabilities during the winter period and to provide the starting date of the Vitis vinifera sprouting vine, Cabernet Sauvignon cultivar. The study was conducted from a historical series (1984-1993) of climate data and phenological data from the Active Germplasm Bank, both from Embrapa Grape and Wine, in Bento Gonçalves, RS. The accumulation of cold was quantified using nine different methods: chilling hours below or equal to 7.2°C and 10°C; Dynamic model; and models of Utah and North Carolina in their original versions, modified for high temperatures and adapted to the conditions of the Serra Gaúcha region. In the study of the historical series, the best results (least waste) were obtained from the models of Utah and North Carolina adapted to the climatic conditions of the Serra Gaúcha region.