NC-140 ROOTSTOCK TRIALS IN NORTH AMERICA

Rootstock trials for apple, peach, cherry, and pear have been planted in most of the important fruit producing areas of the continent using uniform plant material and following mutually agreed upon guidelines and data collection procedures.
The 1980–81 apple rootstock trial compares ‘Starkspur Supreme’ on 9 rootstocks and was established in 26 locations in the United States and 2 locations in Canada.
Trees on M.27 were only 12% the size of trees on MAC 24, which were the largest.
Trees on MAC 9 (now named MARK) were similar in size on M.9 or M.9 EMLA and performed well with only 7% mortality and the highest early yield per unit trunk area.
A second apple trial with ‘Starkspur Supreme’ on 19 rootstocks was established in 1984 at 27 sites in the United States, 4 in Canada and one in Mexico.
Trees on Bud 9, C6, P2, P16, P22 and M.26 EMLA appear the most precocious judged by bloom/tree at 2 years of age.
In 1984, a planting of ‘Redhaven’ peach on 9 rootstocks was established at 16 sites.
In most locations, Lovell is proving to be a superior rootstock.
Cold injury to the scion has been commonly found on ‘Redhaven’ grafted to Damas 1869, GF 655–2, and GF 677.

IV International Symposium on Research and Development on Orchard and Plantation Systems

D.C. Ferree, R.L. Perry

https://doi.org/10.17660/ActaHortic.1989.243.5