Performance of the apple cultivar Jonathan on clonal rootstocks in southern Queensland

Abstract

The final results are reported of a 20-year-old trial with Jonathan as the scion variety on a range of Malling-Merton rootstocks (MM107, MM108, MM109, MM110, MM111, MM113, MM114 and MM115), Malling 411, Malling 279, M25 and Northern Spy under infertile, unirrigated conditions at a 6m by 6m spacing. MM109 produced the largest ·girth, the heaviest scion weight and the heaviest crops. Girth, scion weight and yield of trees on Northern Spy compared unfavourably with most of the other rootstocks. However, Northern Spy and MMllO induced the greatest fruitfulness. On Northern Spy, fruit was of good size, but MMllO produced the smallest fruit in the trial.