Final evaluation of nine plum cultivars grafted onto two rootstocks in a trial established in 1998 at Holovousy
Nine plum cultivars newly introduced into production were evaluated in a replicated trial established in 1998 on two rootstocks planted in a spacing of 5 × 1.5 m. Trees were trained as spindles and evaluated regarding vigour, canopy performance, level and stability of yields, yield efficiency, fruit size, time of flowering and harvest season until 2010. Significant differences among cultivars were found but the most interesting were related to tree vigour, yield efficiency and fruit size. Dwarfing influence of Wangenheim seedling was negligible in Empress and Čačanska lepotica but mostly visible in Sanctus Hubertus. Wegierka Dabrowicka on both the rootstocks had the highest yield efficiency, exceeding 3 kg/m<sup>3</sup> of trunk cross-section area. Yield efficiency of trees grafted on Wangenheim was generally higher than those grafted on Myrobalan but the greatest difference was evidenced on Domestic Prune (more than 25%). Suggestions in terms of trees-spacing are definitively proposed upon results of this study.