Performance of ‘Gala’ Apple on Four Semi-Dwarf Rootstocks: A Five-Year Summary of the 1994 NC-140 Semi-Dwarf Rootstock Trial

Abstract

In 1994, trees of ‘Gala’ apple ( Malus x domesticaBorkh.) on 4 semi-dwarf rootstocks were planted at 24 sites in North America according to the guidelines established for cooperative testing by the North Central Regional Cooperative Project (NC-140). The four rootstocks were P.1, V.2, G.30, and M.26 EMLA. Tree losses were greatest for G.30 and M.26 EMLA. Trunk cross-sectional area was generally largest for trees on P.1 and smallest for trees on G.30. Tree height was usually greatest for P.1 and tree spread was usually smallest for M.26 EMLA. Although results were not consistent for all sites, yield and yield efficiency (YE) tended to be highest for G.30 and lowest for P.1. When adjusted for number of fruit per tree, fruit size was influenced by rootstock at only 7 sites. Trees on P.1 produced the smallest fruit at 5 of those 7 sites.