Abstract
During the nine years (2002-2010) 6 apple cultivars, scab-resistant or partially resistant to apple scab: ‘Bohemia’, ‘Topaz’, ‘Rubinola’, ‘Goldstar’, ‘Pinova’ and ‘Redkroft’ grafted on 3 dwarfing rootstock: M.9, P 22 and P 60, were tested at the Experimental Orchard in Dąbrowice with integrated fruit production. The susceptibility to apple canker (Nectria sp.), apple scab and powdery mildew, as well as growth, yielding, fruit quality and damage by pests were observed. After 9 years, the highest number of infected trees, on trunks and branches, were observed on the cultivars: ‘Topaz’, ‘Bohemia’, and ‘Redkroft’. All the cultivars grafted on P 60 rootstocks formed the largest trees, whereas on P 22 the smallest. The highest yields were obtained from all the cultivars grown on P 60 and the smallest on P 22. The cropping efficiency index was the highest for: ‘Bohemia’, ‘Rubinola’, ‘Goldstar’ and ‘Pinova’ on P 22. ‘Topaz’ had the highest cropping efficiency on P 60 and ‘Redkroft’ on M.9 and P 60. In the last three years (2008-2010), the effect of rootstock on fruit quality was minimal and not significant. Apple scab and powdery mildew, and some important pests, were not observed after applying on integrated system of spraying. The apple cultivars: ‘Bohemia’, ‘Rubinola’, ‘Topaz ‘and ‘Redkroft’ are the most promising for processing and amateur orchards with the integrated system of management. The cultivars: ‘Pinova’ and ‘Goldstar’ should not be recommended for growing on light soil in the integrated system of production. The fruits of ‘Goldstar’ are susceptible to bitter pit.