Interstem/rootstock combinations influence stem and leaf characteristics of spurs and extension shoots of 'Ruby Jon' apple trees.

摘要

The influence of interstem and rootstock combinations on leaf area per spur and average leaf size of spurs and diameter of current season spur stem, and the average size of midterminal extension shoot leaves of Ruby Jon on 30 different interstem/rootstock combinations or rootstocks alone was evaluated in September 1999 [place not given]. In the third leaf, the treatments induced either ultradwarf ( < 0.70 m3), dwarf (0.80-1.60 m3), semidwarf (1.9-2.10 m3) or vigorous scions. Treatments induced spurleaf size that ranged from 7% larger to 28% smaller than on the industry standard, Ruby Jon/MM. 111. Total spur leaf area ranged from 25% greater to 20% smaller compared to Ruby Jon/MM.111 and spur stem diameter was 30% greater-12% smaller. The ultradwarfs tended to produce larger spur stem diameters (e.g. G.65/BUD.118) than the industry standard, while more vigorous treatments (e.g. P.18) had smaller spur stem diameters. Spur leaf size was positively correlated with fruit size on the semidwarf and dwarf trees. There was also a positive correlation between whole spur leaf area and fruit yield in the vigorous and dwarf scions.