EVALUATION OF 9 APPLE ROOTSTOCKS THE FIRST CROPPING YEARS IN A NORTHERN CLIMATE

J. Ystaas, O. Frøynes, M. Meland
The performance of nine apple rootstocks (B.9, Bemali, J-TE-B, J-TE-E, J-TE-F, P.1, P.22, M.26, M.9) with the commercially important cultivars 'Gravenstein' and 'Aroma' was assessed in a field trial at Ullensvang Research Centre, western Norway (at 60°North). The trial was located on a sandy loam high in organic matter; trickle irrigation was provided. Soil management was grass in the alleyways and herbicide strips 1-m-wide along tree rows. Two-year-old trees of good quality were planted in spring 1993. Planting distance was 4 x 1.5 m (1167 trees/ha) and the trees were trained as slender spindles. Tree size of both cultivars was significantly affected by rootstocks; trees on P.1, M.26, Bemali and B.9 were more vigorous than those on M.9, P.22, J-TE-B, J-TE-E and J-TE-F as measured by the trunk cross-sectional area. The number of flowers and yield obtained in the second and third year after planting were strongly influenced by rootstocks; trees of both cultivars were most precocious on M.9 and slow to start cropping on P.1. Trees on M.9 had the highest yield efficiency, significantly higher than trees on any other rootstock in the trial. Fruit weight was affected by rootstocks; 'Aroma' apples were significantly larger on M.9 than on B.9 and P.1. Fruit quality characterized by content of soluble solids, ground color and red surface color did not differ between trees on various rootstocks.
Ystaas, J., Frøynes, O. and Meland, M. (1997). EVALUATION OF 9 APPLE ROOTSTOCKS THE FIRST CROPPING YEARS IN A NORTHERN CLIMATE. Acta Hortic. 451, 147-152
DOI: 10.17660/ActaHortic.1997.451.13
https://doi.org/10.17660/ActaHortic.1997.451.13
Apple, cultivar, rootstock, yield, yield efficiency, fruit size, fruit quality

Acta Horticulturae