Table 2. Cumulative yield per tree (1992-96) at the end of the 1996 growing season. 



Rootstock 



Golden 

 Delicious 



M.9EMLA 



B.9 



Mark 



0.3 



M.26 EMLA 



Average 



Site 



74 b 

 69 be 

 61 c 

 94 a 

 89 a 



78 b 



Arkansas 



Colorado 



Iowa 



Indiana 



Kansas-Manhattan 



Kansas-Wichita 



Kentucky 



Massachusetts 



Maine 



Ohio 



Pennsylvania 



Tennessee 



Utah 



Virginia 



Cumulative yield (kg/tree, 1992-96) 



Jonagold 



Empire 



74 b 

 60 c 

 54 c 

 81 ab 

 85 a 



71c 



71 b 

 53 c 

 43 d 

 83 a 

 77 ab 



66 d 



Cumulative 



yield (kg/tree 



1992-96) 



21 1 



32 h 



33 h 



48 fg 

 139 b 

 126 c 

 80 d 

 86 d 

 54 f 



149 a 



49 gh 

 35 h 

 65 e 



150 a 



Rome 



96 a 

 79 b 

 62 c 

 102 a 

 95 a 



87 a 



Average 



80 b 

 65 c 

 55 d 

 90 a 



87 a 



Rootstock means within columns, average rootstock means, average cultivar means, or 

 average site means are significantly different at odds of 19:1 if not followed by the same 

 letter. 



the most efficient, those on M.26 EMLA were 

 the least efficient, and those on Mark, M.9 

 EMLA, and 0.3 were intermediate. Rome 

 trees, overall, were the most yield efficient, and 

 Jonagold trees were the least efficient. Ohio 

 and Massachusetts produced the most yield- 

 efficient trees, and Arkansas produced the 

 least efficient. 



This study, which will continue through the 

 tenth growing season, has demonstrated 



variation in the effects of rootstock with 

 different cultivars. To date, however, the 

 importance of the variation is minimal. Tlie 

 reduced size of Jonagold trees on 0.3 is an 

 important deviation ft-om the response with 

 other cultivars. The tree is smaller than 

 expected, but it is as yield efficient as it should 

 be. Unless this observation is a reflection of 

 some level of incompatibility between scion and 

 rootstock, the only change that a grower needs 



Fruit Notes, Volume 63 (Number 1), Wmter, 199H 



