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Remote optical imaging can rapidly acquire information describing spatial variability in vineyard block performance. Canopy characteristics were derived from very high spatial resolution (0.25 m) optical imagery of a Cabernet Sauvignon vineyard acquired at various canopy growth stages. Within-season changes to correlation coefficients between vineyard canopy and ultimate composition and yield of harvested fruit were then investigated. Canopy area and density were observed to have significant relationships with yield and fruit quality indicators including berry size, anthocyanins and total phenolic content, but less significant relationships with total soluble solids. The strength and type of correlation varied with canopy growth stage. For anthocyanins and total phenolic content, correlations varied from non-significant before flowering to negative after flowering. For berry weight and yield, correlations varied from negative before flowering to positive after flowering. For total soluble solids, there were some significant relationships but no clear temporal pattern. The results confirm that remote sensing is a useful tool to determine spatial variability in fruit composition and yield. However, both the timing of image acquisition and the way in which canopy is quantified are important determinants of the direction and strength of correlations with fruit composition and yield.

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Significance of the Study: Without appropriate adaptations, some established viticultural regions of Australia may become less suitable for quality winegrape production, whereas regions that were once considered unsuitable for quality winegrape production may become more suitable. Abbreviations

Aims: This research analyzes four climate indices derived from gridded, interpolated data to assess New Zealand's climate structure and variation among wine regions. Methods and results:High resolution gridded data based on 1971-2000 climate normals was used to characterize climate indices depicting viticultural suitability in a geographic information system. The statistical properties of each index were assessed over 21 New Zealand viticulture regions. The results show predominately cool to moderately warm climate suitability in New Zealand, comparable to many European and United States regions. While many viticulture regions have one primary class of suitability, variability of climate within regions can be significant, with some regions containing two to four climate classes, making them suitable for a greater range of cultivars. Conclusion:While the indices depict broad patterns expected over New Zealand, both within and between region variations can be substantial among the indices. However, two indices, Growing Season Average Temperature (GST) and Growing Degree-Days (GDD), are functionally identical, but GST is easier to calculate and overcomes many methodological issues in GDD.Significance and impact of the study: This research provides the basis for evaluating general suitability for viticulture in New Zealand, assists comparisons between viticulture regions in New Zealand and worldwide, and offers growers measures of assessing appropriate cultivars and sites. AbstractRésumé

Carbohydrates are accumulated within the perennial structure of grapevines when their production exceeds the requirements of reproduction and growth. The period between harvest and leaf-fall (the post-harvest period) is a key period for carbohydrate accumulation in relatively warmer grape-growing regions. The level of carbohydrate reserves available for utilisation in the following season has an important effect on canopy growth and yield potential and is therefore an important consideration in vineyard management. In a warming climate, the post-harvest period is lengthening and becoming warmer, evidenced through studies in wine regions worldwide that have correlated recent air temperature increases with changing grapevine phenology. Budbreak, flowering, veraison, and harvest have all been observed to be occurring earlier than in previous decades. Additionally, the final stage of the grapevine phenological cycle, leaf-fall, occurs later. This study explored the potential for increased post-harvest carbohydrate accumulation by modelling heat accumulation following harvest dates for the recent climate (1975-2004) and two warmer climate projections with mean temperature anomalies of +1.26 and +2.61 °C. Summaries of post-harvest heat accumulation between harvest and leaf-fall were produced for each of Australia's Geographical Indications (wine regions) to provide comparisons from the base temperatures to projected warmer conditions across a range of climates. The results indicate that for warmer conditions, all regions observe earlier occurring budbreak and harvest as well as increasing post-harvest growing degree days accumulation before leaf-fall. The level of increase varies depending upon starting climatic condition, with cooler regions experiencing the greatest change.

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