Within-vineyard variability in vine vegetative growth, yield, and fruit and wine composition of Cabernet Sauvignon in Hawke's Bay, New Zealand

Abstract

Background and Aims Spatial and temporal variability of vine vigour within a vineyard block, associated with variation in soil physical and chemical properties, affects yield, and fruit and wine composition. The objectives of this study were to measure this variability and possible causes for a commercially important vineyard area in Hawke's Bay, New Zealand. Methods and Results Three vigour classes, and measurement of vine nutrient and water status, vegetative growth and canopy attributes, yield, fruit ripening profiles, and grape and wine composition over two seasons characterised vigour variability of Cabernet Sauvignon vines growing on the ‘Gimblett Gravels’ area of Hawke's Bay, New Zealand. Vine nutrition and growth differed between vigour zones with extreme nitrogen deficiencies recorded. Vigour did not affect vine phenology. Normalised Difference Vegetative Index measurements quantified vigour differences. High vigour vines showed a higher yield, but fruit ripeness, wine anthocyanins and phenolics, and some sensory attributes were significantly reduced. Excessively leafy canopies associated with high vigour were responsible for these effects. Conclusions Soil-induced vine nutrient deficiencies, rather than differences in vine water status, influenced vine vigour. Measures of vegetative growth and canopy attributes suggested negative implications of excessive shading with high vine vigour. Significance of the Study This study showed the relative significance of nutrition in affecting vine vigour on sandy gravel soils. A good correlation between remotely sensed vigour zones, and grape and wine composition permit on-ground zonal management to minimise the negative effects of spatial variability.