Performance of an Established Dwarf Apple Rootstock Trial (2003 NC-140)

To evaluate the adaptability and performance of new and promising apple rootstocks in the dwarfing sizecontrol category, a NC-140 regional rootstock trial was established in 2003 at 14 sites in the United States (AR, CA, IA, GA, KY, ME, MI, NY, OH, PA, UT, WI), Canada (BC), and Mexico. The Iowa planting, located at the ISU Horticulture Research Station, includes 23 rootstocks with new selections from the CornellGeneva breeding program (G, CG.), Russia (B.), Czech Republic ( J-TE), Japan ( JM), and Germany (PiAu) with M.26, M.9 Pajam 2, and M.9 T337 serving as industry standards. These rootstocks are being evaluated with Gibson Golden Delicious serving as the test cultivar. This report summarizes the tree-growth and production characteristics through the 2010 growing season.