The influence of crown shapes on quantitative and qualitative parameters of nectarine yield

The quality of fruit is an ensemble of specific traits and characteristics which, together with other criteria, influence the choice and the promotion of the assortment, depending on the demand on the market. The research took place over a period of four years at the Research Station for Fruit-Growing (RSFG) Constanţa, in an experimental plot, planted in the spring of 2002. Four nectarine tree cultivars were studied, three of which are Romanian cultivars, created and homologated at RSFG Constanţa (‘Cora’, ‘Delta’ and ‘Romamer 2’), the other cultivar was of American origin (‘Crimsongold’). The quality of the fruit was also determined: the average weight of the fruit, the average weight of the stones, stones percentage, dry matter, titratable acidity. The aim of this study was to evaluate the influence of canopy shapes on and qualitive parameters of yield at some nectarine cultivars with late ripening (‘Cora’, ‘Delta’, ‘Romamer 2’ and ‘Crimsongold’) using fruit quality methods (size, sugar content, acidity, dry matter). The dry matter had values ranging between 10% for the fruit of the ‘Crimsongold’ and 10.8% for ‘Romamer 2’, the variation between cultivars being reduced. Within the canopy shape of the trees which were studied, the average acidity value was 0.89% as average for the years 2008-2011 for the shape Improved vase and 0.91 g% for Tatura and Veronese vase. It was noted that the shape Tatura might influence the size of the fruit, this shape having larger fruit (98.2%g g^‑1), whereas the Vertical vase recorded the smallest weight of the fruit, 92.2%g g^‑1.