Plum Cultivar Evaluation on Myrobalan Rootstock in Lithuania

Twenty plum cultivars on Myrobalan (Prunus cerasifera Ehrh.) seedling rootstock were tested in 2012–2017 at the Institute of Horticulture of the Lithuanian Research Centre for Agriculture and Forestry. Plum trees were spaced at 4.5 × 2.5 m and trained as spindles. Orchard floor management included frequent mowing of grass in the alleyways with herbicide strips along tree rows. ‘Duke of Edinburgh’, ‘Kijevas Vēlā’, ‘Dąbrowicka Prune’, ‘Čačanska Najbolje’, ‘and ‘Štaro Vengrinė’ cultivars were the most vigorous plum trees at the end of 6^th year. Their trunk diameter achieved 92–96 mm. ‘Valor’, ‘Queen Victoria’, ‘Herman’, ‘Čačanska Najbolje’, ‘Favorita del Sultano’, ‘Ave’, and ‘Jubileum’ cultivars had the lowest trunk diameter — 72–78 mm. The highest cumulative yield of four fruiting years was recorded for ‘Kometa’ and ‘Violeta’ cultivars, respectively, 43.0 and 46.5 kg/tree. ‘Favorita del Sultano’, ‘Rausvė’, and ‘Kijevas Vēlā’ produced the largest fruits — 52–60 g. The smallest fruit occurred on ‘Dąbrowicka Prune’ and ‘Herman’ cultivars, respectively, 22 and 25 g. ‘Dąbrowicka Prune’ had the highest soluble solids content (SSC) — 19.5%. The least SSC was recorded in ‘Kometa’, ‘Violeta’ and ‘Herman’ fruits — 10.6–11.8%. ‘Renklod Rannij Doneckij’, ‘Čačanska Najbolje’, and ‘Valor’ cultivars had the highest fruit flesh firmness.