Long-term evaluation of rootstock effects on cropping and tree parameters of selected sweet cherry cultivars

The cropping of six sweet cherry cultivars that originated in the Research and Breeding Institute of Pomology at Holovousy, and a standard one, ‘Burlat’, were evaluated on three rootstocks in the period of 2007–2017. Trees planted in a spacing of 1.5 m × 5.0 m were trained as tall spindle axes utilising their natural tendency to develop a central leader. On the standard rootstock, P-TU-2, ‘Tim’ was the most productive with a mean total harvest of 47.6 kg per tree. ‘Sandra’ yielded the most on the PHLC rootstock with 56.2 kg per tree and ‘Helga’ yielded the most on Gisela 5 with a mean total harvest of 55.9 kg per tree. The mean impact of the rootstock on the tree vigour, measured upon the trunk cross section area, ranged from 148.4 cm2 on the standard rootstock P-TU-2 to 114.1 cm2 on the PHLC and 125.2 cm2 on Gisela 5 . On the standard rootstock P-TU-2, the most vigorous one according to this criterion was ‘Jacinta’ (178.0 cm2) whereas ‘Justyna’ (109.7 cm2) was the least vigorous. On the PHLC, the most vigorous was ‘Sandra’ (147.2 cm2) and the least was ‘Amid’ (94.0 cm2). The other tree characteristics were mainly dependant on the cultivar and minimally, or not at all, influenced by the rootstock vigour.