Productivity of a Selection of Spindle-grown Plum Varieties During the Full-yield Stage.

In the conditions of the Czech Republic, a trial was conducted in 2012–2016 to evaluate the growth and yield of 16 spindle-grown plum varieties grafted on rootstocks St. Julien A, Wangenheim, Wavit and WaxWa. The trial was established in autumn 2005. As to the yield, 'Tophit' seems to be an interesting variety. This semi-prune reached high and regular fruit yields (44.1 kg/tree on average) on all rootstocks with the mean fruit weight of 60–70 g. The vigour of 'Valjevka' and 'Čačanska Rana' trees was significantly weakened by the Wangenheim rootstock compared to St. Julien A. At evaluating the mean fruit weight of 'Elena' and 'Tophit' varieties, a negative influence of the Wangenheim rootstock on this parameter was observed compared to St. Julien A. The mean fruit weight of the evaluated prunes and semi-prunes varieties ranged from 24.8 g at 'Top 2000' (Wavit) to 76.14 g at 'Čačanska Rana' (St. Julien A). A positive correlation was proved between trunk increment and fruit yield in the following year at all studied combinations of varieties and rootstocks; the strongest dependence was observed in plum trees on the Wavit rootstock. [ABSTRACT FROM AUTHOR]