Early Production of Apple Cultivars on M.9 and Mark Rootstock

Abstract

After six years there was little difference in tree size or yield of three apple cultivars on Mark or M.9 rootstocks. Yields of all cultivars in this trial were relatively low and growth was vigorous resulting in large tree size. TCA of both the spur (‘Redchief’) and standard habit ('Top Red') ‘Delicious’ strains were larger on Mark than on M.9. ‘Melrose’ tended to produce larger trees and was more precocious than the other cultivars in this study on M.9. ‘Smoothee’/M.9 had equivalent cumulative yield/ha than other cultivars and had the highest production efficiency of all combinations in this study. It is suggested that training techniques to reduce growth and encourage flowering are needed when trees on dwarfing rootstocks are grown on high fertility soils in order to achieve production efficiency.