Acta Hortic. 1285. ISHS 2020. DOI 10.17660/ActaHortic.2020.1285.25 XXX IHC – Proc. II Int. Symp. on Micropropagation and In Vitro Techniques Eds.: M. Lambardi et al. 161 In vitro propagation in different media of some cherry genotypes as candidate rootstocks for cherry E. Aydın 1,a , H. Demirsoy 2 and T. Yarılgaç 3 1 Blacksea Agricultural Research Institute, Samsun, Turkey; 2 Ondokuz Mayıs University, Faculty of Agriculture, Department of Horticulture, Samsun, Turkey; 3 Ordu University , Faculty of Agriculture, Department of Horticulture, Ordu, Turkey. Abstract In this study, possibilities of in vitro production of cherry and sour cherry genotypes, candidate rootstocks, were investigated. The study was carried out in the tissue culture laboratory of Aksa Agriculture, Turkey. The lateral and top buds of annual shoots were used as explants. The buds were taken at different times of the year and the media used were MS (Murashige and Skoog), WPM (Woody Plant Medium) and QL (Quoirin and Lepoivre), supplied with 0.1 mg L -1 IBA, 0.1 mg L -1 GA3, 1.0 mg L -1 BAP. During the propagation phase, explants were placed in growth chambers under a 16 h photoperiod, with a light intensity of 41 mol m -2 s -1 , and temperature of 25±1°C. Explants were subcultured for 4 weeks. Contamination rates in explants taken in June were lower. In the genotypes candidate for cherry and sour cherry rootstocks, the MS medium has a higher degree of multiplication rate. Keywords: cherry, in vitro, MS, rootstocks, shoot multiplication INTRODUCTION Turkey has a lot of potential in terms of fruit growing. There is ecological wealth in our country where almost all temperate climate fruits can grow (Baş, 1998). Cherry, a significant fruit in temperate climate fruits, belongs to Rosales group, Rosaceae family, Prunoidae subfamily, Prunus genus. Turkey has appropriate ecology for cherry growing. There was a cherry production in the world of 2.3 million t in 2016, and Turkey is the first producer with 599,650 t (FAO, 2016). Cherry is grown by grafting on clonal rootstock. Cherry production mostly uses mazzard (Prunus avium), sour cherry (Prunus cerasus) and mahaleb (Prunus mahaleb) seeds, despite sapling production preference is for clonal rootstocks as there is an evolution owing to heterozygous structures (Webster and Looney, 1996). Additionally, modern fruit growing uses clonal rootstocks to ensure genotype continuity, uniform population, decrease infertility time and early fruit production (Yılmaz, 1992; Soylu, 2000). Clonal rootstock propagation allows to raise production per unit. In particular, harvest is very costly for cherry and sour cherry, hence to have an optimum tree habitus is especially important. Moreover, the use of dwarf rootstocks raises the production per unit, the quality, and decreases labour costs. Clonal rootstocks are reproduced by cutting propagation, while with some rootstocks it is possible to apply layering propagation. In vitro practices are also commonly used for obtaining numerous saplings in a short time (Hepaksoy, 2004). Chery and sour cherry in vitro propagation usually used micro- and macroelements from MS medium, sometimes with modifications. For instance, the increase of iron amount is applied to counteract the appearance of chlorosis symptoms. As for sucrose concentration, it is sometimes beneficial to use concentrations higher than the common 30 g L -1 . Moreover, Prunus cultures prefer solid media instead of liquid media, and 6-8 g L -1 of agar is the suitable concentration (Skirvin and Chu, 1979; Skirvin, 1984; Borkowska and Szczerba, 1991; Morini et al., 1992). As for the cherry clonal rootstocks ‘Gisela 5’, ‘M×M 14’ and ‘Tabel Edabriz’, there are no particular problems in the introduction in vitro, except for infection during subculturing. But, during shoot multiplication, vitrification is an important problem. The in vitro culture of ‘Gisela 5’ on a E-mail: yomra_erol@hotmail.com