Performance of Plum Rootstocks with ‘Stanley’, ‘Valor’, ‘Veeblue’ and ‘Santa Rosa’ as the Scions in the 1991 NC-140 Multi-State Plum Trial

Abstract

In 1991, a multi-site replicated plum rootstock trial was established by the Cooperative Regional Pome and Stone Fruit Project (NC-140) at Indiana (IN), New York (NY), Oregon (OR) and South Carolina (SC), using ‘Stanley’, ‘Valor’, ‘Veeblue’, or ‘Santa Rosa’ plums as the scions. The trial compared vigorous and semi-dwarfing plum rootstocks to identify improved rootstocks and rootstock/scion combinations best suited to the various production areas in the United States. Trees on Mariana 2624 and Mariana 4001 rootstocks generally had the best tree survival, cumulative yields, trunk cross-sectional areas, cumulative yield efficiencies, and fruit sizes but had the most root suckers, irrespective of the scion or location. Trees on Pixy rootstock had the smallest trunk cross-sectional area, lowest cumulative yield, and cumulative yield efficiency, and smallest fruit size. Trees on Eruni had similar survival, tree size, yield, and yield efficiency as the Mariana stocks but fewer root suckers. It may be a good alternative to the Mariana and Myrobalan rootstocks. No significant differences were observed between rootstocks with ‘Valor’ and ‘Veeblue’ scions for most variables. The Oregon site had the largest trunk cross-sectional areas, but the NY site had the highest yield and yield efficiency. Stanley used as a rootstock (only tested in Oregon) had high yield efficiency, and a low number of root suckers but also high vigor.