The influence of solar radiation and temperature on the accumulation of berry skin anthocyanins was evaluated in Vitis vinifera L. cv. Nebbiolo during ripening. In 2006 and 2007, five fruit-zone light exposure regimes were established using plastic netting or leaf removal. Shading was applied in three periods: from fruit set to veraison, from fruit set to harvest, and from veraison to harvest. Fruit-zone shading had no impact on yield per vine and cluster weight, but early fruit-zone shading caused a slight delay in berry development, although it did not lead to lower berry size at harvest. Fruit-zone shading reduced total soluble solids and anthocyanin accumulation. Generally, fruit shading decreased the 3′-hydroxylated anthocyanin concentration and increased the 3′,5′-hydroxylated anthocyanin concentration. Fruit-zone leaf removal caused a delay of berry development, but did not affect berry size, cluster weight, or yield at harvest. Excessive sunlight exposure caused sunburn damage and did not increase total soluble solids or anthocyanin accumulation.
- Copyright © 2010 by the American Society for Enology and Viticulture