Table 4. Surface red color (%) of fruit from Summerland Red 

 Mcintosh trees on seven rootstocks." 



Within columns, means not followed by the same letter are 

 significantly different at odds of 19:1. 



Conclusions 



The ideal rootstock for any particular cultivar is the 

 one that results in the best return to the grower. Generally, 

 the best return is the result of high yields of fruit which are 



of large size and good color. 



In this trial, trees on Mark and those 

 on 0.3 were high yielding, in terms of 

 either yield efficiency or projected yield 

 per acre. They were not significantly 

 greater in terms of cumulative yield per 

 acre, however, than trees on M.26 

 EMLA, M.9/A.2, or M.7 EMLA. To 

 determine which of these rootstocks per- 

 formed the best, other factors, such as 

 size and color, must be considered. In 

 this study, 0.3, M.26 EMLA, and M.9/ 

 A. 2 resulted in fruit size in the largest 

 category each year, and Mark tended to 

 result in fruit in the smallest category, 

 although not consistently. Color, on the 

 other hand, was consistently greater for 

 fruit from trees on Mark. M.7 EMLA 

 and M.7A resulted in the poorest color- 

 ing. 



Although the results may not be ab- 

 solute, 0.3 appears to have performed 

 the best. It met the criterion of producing high yields of 

 large and relatively well colored fruit. M.26 EMLA and 

 M.9/A.2, however, also performed well. Mark's effects on 

 fruit size Vv-ere a significant detriment, as were M.7 EMLA's 

 and M.7A's effects on red color development. 



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Fruit Notes, Winter, 1995 



