|Hampson, Cherly - AG & AG FOOD CANADA, BC|
|Mcnew, R. - UNIV OF ARKANSAS|
Submitted to: Journal of American Pomological Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 5, 2004
Publication Date: April 1, 2004
Citation: Hampson, C.R., Mcnew, R., Miller, S.S. 2004. Performance of 'braeburn', 'golden delicious' and 'yataka' apple on mark and m.9 rootstocks at multiple locations across north america. Journal of American Pomological Society. 58:78-89, 2004 Interpretive Summary: The objective and systematic evaluation of apple cultivars across many planting sites in North America would provide valuable assistance to growers in selecting new cultivars to plant. In addition, consumers would be able to make informed purchasing choices if provided with fruit quality descriptions. A regional project was initiated in 1995 to evaluate apple cultivars on Mark and Malling 9 rootstock planted at 19 sites across North America. The present paper compares the performance of three cultivars, 'Braeburn', 'Golden Delicious', and 'Yataka', on the two rootstocks. Rootstock had little or no effect on some fruit quality factors while others, such as flesh firmness, were affected. Rootstock did affect tree size, but the strongest effects were related to location. This information is proving valuable for recommendations made by tree fruit extension and fruit consultant personnel.
Technical Abstract: The performance of three apple (Malus x domestica Borkh.) cultivars ('Braeburn', 'Golden Delicious' and 'Yataka') on two dwarfing rootstocks (M.9 EMLA and Mark) was followed for five years at multiple sites across North America as part of a large international cultivar evaluation trial. The effect of rootstock on cultivar performance was examined. Whether trees were propagated on Mark or M.9 EMLA made no difference to cultivar comparisons of the number of days between bloom and maturity, nor fruit red color, soluble solids content, or length: diameter ratio, but these measures were affected by location and/or location x cultivar interaction. Scion differences in bloom density ratings were consistent across all rootstocks and locations, with 'Braeburn' having the greatest bloom density, followed by 'Golden Delicious', and then 'Yataka.' Skin russet was unaffected by rootstock; 'Golden Delicious' had slightly more russet than 'Braeburn'. Rootstock affected flesh firmness consistently, with fruit from trees on Mark being 0.6 pounds firmer than on M.9. Rootstock differentially affected cultivar fruit size, flesh titratable acidity and yield efficiency. However, the cultivar x rootstock interaction effect was small compared to location differences for fruit size and yield efficiency, and its effect on fruit acidity was limited to one location. Rootstock influenced cultivar tree size (trunk cross-sectional area, tree height and spread), but the presence, direction and magnitude of the rootstock effect varied with location and cultivar. At sites and for scions where tree size differed significantly between rootstocks, trees on Mark tended to be larger than those on M. 9 in sites with cold winters and smaller than on M. 9 in southern sites. Rootstock also affected cumulative yield; the extent and direction of the effect varied with location but not cultivar. At the majority of locations, 'Golden Delicious' was more productive than 'Braeburn', but not more yield-efficient. At 13 of 19 locations, 'Golden Delicious' was more yield-efficient than 'Yataka'.