Effects of hormones on shoot-tip culture micropropagation of strawberry via shoot

In this study, the effects of different hormones and their doses on the micropropagation and rooting of four strawberry variety candidates selected from last step of breeding program (291 and 299) and 'Rubygem' and 'Kaşka' varieties which are used as parents in the obtaining of these candidates were investigated via using shoot-tip culture. In the research, five different Murashige ve Skoog (MS) nutrient media combinations containing 6-Benzylaminopurine (BAP) and Thidiazuron (TDZ) at the ratios of 0.75 mg L-1 and 1.50 g L-1 were tested. All nutrient media contained 30 g L-1 sucrose and 8 g L-1 agar as standard. During study; darkening rate (%), infection rate (%), shoot number/plant, rooting rate (%), root number/shoot and root length (cm) parameters were examined. As a result of the study, it was found that TDZ was more effective than BAP in micropropagation, however the results varied according to the genotypes. In the first subculture, it was noted that the maximum number of shoots per explant were obtained from Medium 5 containing 1.50 mg L-1 TDZ as approximately 3-4 in all genotypes tested except genotype 299. For the same parameter in the second subculture, 6.0 and 4.5 shoots were observed in 289 genotype and Kaşka, respectively in the medium containing 1.50 mg L-1 TDZ. However, in the same subculture, Rubygem and genotype 299, 0.75 mg L-1 BAP gave better results than TDZ. In the rooting parameters, it was determined that the hormone-free MS medium was generally sufficient and successful tested expect. In the study, it was concluded that the selection of the appropriate hormone type and dose was very important in micropropagation of each strawberry genotype.