In the years 2011–2013 growth and yielding of four cultivars of sweet cherry trees: Burlat’, ‘Regina’, ‘Summit’ and ‘Vanda’ were evaluated. All of them were grafted on new Mahaleb rootstocks obtained through softwood cuttings selected from a population of German seedlings of ‘Alpruma’ type in comparison with Mazzard seedling. Additionally an analysis of genetic variability of newly studied biotypes of Mahaleb was conducted. The biggest trunk cross-sectional area had trees on seedlings of Mazzard and Mahaleb No.1, No.4 and No.5, and the smallest on Mahaleb No. 2, No. 3 and No. 6. The biggest volume of the crown had trees growing on Mazzard and the smallest on Mahaleb No. 2 and No. 6. Bigger crowns were also created by the trees of ‘Burlat’ and ‘Summit’ cultivars, and smaller ‘Regina’ and ‘Vanda’. Trees budded on Mazzard had fruits which were slightly lighter in comparison to Mahaleb rootstocks. Regina and Summit outstood other cultivars in terms of weight of fruits. The biggest sum of crops was obtained from trees budded on Mahaleb No. 6 and No. 2, and the smallest on Mazzard and Mahaleb No. 1 and No. 4. The most productive were ‘Vanda’ and ‘Summit’. The biggest productivity index was obtained for rootstocks of Mahaleb No. 6, No. 2, No. 3 and No. 5. For Mazzard and and Mahaleb No. 1 the value of this index was the smallest. Of all examined cultivars the best results was Vanda, then Summit. The analysis of electrophoretic profiles conducted with PCR-RAPD method showed a big genetic similarity between Mahaleb No. 2 and No. 6 and a big variability of the remaining biotypes of Mahaleb among each other. Out of six examined biotypes, Mahaleb No. 2 and No. 6 turned out to be the most productively valuable. Trees of sweet cherry on these rootstocks had the weakest growth, had relatively many flowers and fruits and were characterized with the biggest productivity index.

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