Apple Rootstock Trials

摘要

Abstract Results of a rootstock trial on fertile irrigated land are presented. Three woolly-aphid-immune rootstock selections, Merton 779, 789, and 793, were compared with Malling XVI, MaIling XII, and a clonal selection of Northern Spy. The scion varieties were Delicious and Sturmer. Sixteen years from planting, trees on Malling XII were largest and produced heaviest accumulated yields per tree, but could be recommended only for 20 ft x 20 ft spacing, when annual yields of 900 to 1,000 bushels per acre could be expected. For more intensive plantings at 16 ft x 12 ft spacing, it was calculated that trees on Merton 793 could produce about 1,400 bushels per acre. Trees on Northern Spy were too small. Malling XVI produced disappointing results and was found to be adversely affected by “tree decline”. The influence of the Quinn pruning system on results of the trial is discussed.