Growth and yielding in six scab-resistant apple cultivars grafted on three dwarfing rootstocks in integrated fruit production.

摘要

During three years (2002-04), six apple cultivars resistant or partially resistant to apple scab (Venturia inaequalis): 'Bohemia', 'Topaz', Rubinola', 'Goldstar', 'Pinova' and 'Redkroft' grafted on 3 dwarfing rootstocks: M.9, P 22 and P 60 were tested at the Experimental Orchard at Dabrowice (Poland) with integrated fruit production. The susceptibility to scab and powdery mildew as well as growth, yielding and fruit quality were observed. All cultivars grafted on P 60 rootstocks formed the largest trees whereas on P 22 the smallest. Cropping efficiency index was the highest for 'Pinova', 'Topaz', 'Bohemia' and 'Rubinola' on P 22. The cultivars: 'Goldstar' and 'Redkroft' had the highest cropping efficiency on M.9. In the third year after planting (2004), the effect of rootstocks on quality of fruits was minimal and not significant. Primary observations show that cultivars having small fruits: 'Pinova' and 'Goldstar' should be not recommended to grow on light soil in integrated fruit production. In the first three years after planting, very little infection of apple scab was observed on 'Bohemia' and 'Pinova' cultivars. Apple mildew was controlled by cutting the infected shoots..