Diameter (vigour) of the fruit bearing canes has a big influence on fruit size and quality in kiwifruit. The aim of the study was to determine its impact on Actinidia deliciosa 'Hayward' and Actinidia arguta 'Issai' in order to devise the proper pruning technique which would yield the highest quality and the biggest size of the fruit. Additionally, the effect of storage parameters, such as weight, firmness and quality of the fruit was also investigated into. It was established that the fruit size and weight is lower in lower vigour canes in A. arguta, but lower in higher vigour canes in A. deliciosa. The cane vigour effects fruit firmness only in A. arguta. The fruits from A. arguta contain higher percentage of total sugars and higher concentration of sucrose compared to A. deliciosa in which glucose and fructose are present in the highest concentrations. The fruits from A. arguta contain more citric acid and less quinic and malic acid compared to A. deliciosa. During storage, total sugars and total phenolic compounds tend to increase and the total organic acids and firmness decrease. Lower vigour canes in A. deliciosa display better fruit quality, however, the differences are not significant. In A. arguta it is recommended that higher vigour canes are left while pruning. It is also recommended to perform the harvest two to three times per season, to achieve more equal fruit quality.
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