Weather and soil effects on the composition of 'Cabernet Sauvignon' grape

The objective of this work was to evaluate the effects of weather and soil type on the physicochemical characteristics and phenolic compounds of the 'Cabernet Sauvignon' grape (Vitis vinifera). The experiment was carried out in a vineyard established in 2003, grafted onto 'Paulsen 1103', and conducted in the cordon system. Two soils were selected in the vineyard: Typic Dystrudepts and Pachic Humudepts. The effect of weather (rainfall, and minimum and maximum temperature) was evaluated in the seasons 2008/2009, 2009/2010, and 2010/2011. Soil physical and chemical properties, soluble solids, titratable acidity and pH of the wort were determined, as well as the index of total polyphenols, and anthocyanin and tannin contents of the grape. The factors soil and meteorological conditions (crop seasons) were arranged in a 2x3 factorial. Except for the total polyphenol content, weather and soil type affect the physicochemical characteristics of 'Cabernet Sauvignon'. The effect of weather is more pronounced than the effect of soil type. Lower rainfall and higher temperature ranges favor the accumulation of soluble solids in the 'Cabernet Sauvignon' grape. Higher rainfall favors the increase of wine acidity.