Apple Rootstock Studies: Fifteen Years’ Results With Some M.IX Crosses

Abstract

SummaryThe field performance of seven new rootstock clones raised from crosses between M.IX and other Mailing rootstocks is reviewed over a 15-year period for Cox’s Orange Pippin and four pollinator varieties. The rootstocks showed a wide range of vigour, resulting in trees that were more dwarfing than those on M.IX and more vigorous than those on M.XVI. Most of the very dwarfing rootstocks suckered badly but trees on 3431 did not. The most valuable rootstock for the fruitgrower was M.26 which made trees larger than those on M.IX but smaller than on M.VII. Fruit size from trees on M.26 was as large as that from trees on M.IX.Trees on rootstocks more dwarfiing than M.VII had given their basic information at 7 years, but with the more vigorous rootstocks it was necessary to secure growth and cropping data up to 15 years. The most dwarfing rootstock, 3426, not of commercial value but of great scientific interest, gave the highest ratio of yield to tree weight. Trees on this root-stock produced more than 20 t...