Influence of the propagation method of three semidwarf rootstocks on the growth and activity of the physiological processes of maiden sweet cherry trees in a nursery

Rootstocks that reduce the vigor of sweet cherry trees are currently in high demand in orchard production. However, their suitability for nursery production is not fully verified. There are also difficulties in the method of their obtaining, mainly through in vitro cultures, which is associated with high prices. The experiment compared the growth of maiden trees of four sweet cherry varieties on rootstocks that reduce their vigor, ‘Gisela 5’, ‘Krymsk 5;, and ‘Pi-ku 1’. In addition, rootstocks produced by cheaper means using shoot cuttings were evaluated compared with those from in vitro. The lower efficiency of maiden trees was obtained on the ‘Krymsk 5’ rootstock than on the other two rootstocks. In contrast, the vigor of maiden trees on this rootstock was significantly more potent. Generally, rootstocks derived from in vitro yielded a higher percentage of maiden trees. Additionally, for most of the varieties and years tested, the rootstocks obtained in this way improved the growth of the trees as determined by their diameter and length of the lateral shoots. The activity of the physiological processes of the maiden trees varied with the rootstock used. Maiden trees on the ‘Krymsk 5’ rootstock were most often characterized by the lowest levels of the three tested parameters (E, C, and I CO2). Meanwhile, the net photosynthetic intensity was lowest on the ‘Pi-ku 1’ rootstock.