Effect of cytokinin and auxin combination on in vitro mikropropagation of Ajuga xylorrhiza kit tan

Ajuga xylorrhiza Kit Tan is a rare and sensitive plant species under the threat of extinction, whose habitat is limited to a certain region, Çermik, a district of Diyarbakır. Conservation and sustainability of the genetic diversity of endemic plant species can be achieved by using plant tissue culture methods. Thus, the present study investigates the effect of cytokinin and auxin combinations on micropropagation in vitro to protect and ensure the genetic diversity and sustainability of Ajuga xylorrhiza Kit Tan, which is under protection. For this, 1.0-2.0 cm in vitro shoots germinated in hormone-free 1/4 MS medium from mature seeds, 4 different kinetin concentrations (0.125-0.25-0.5-1.0 mg/L) and 2 different auxin (IAA and NAA) varieties were cultured in MS medium containing separate combinations of 3 different concentrations (0.1-0.2-0.5 mg/L). The study revealed that shoot growth occurred in all treatments, and IAA concentrations gave better results than NAA concentrations. As a result, the most new shoot formation among all treatment groups was obtained from the medium containing 0.125 mgL-1 Kin+ 0.1 mgL-1 IAA with 10.91 shoots per explant and the lowest shoot formation was obtained from the medium containing 0.5 mg/L Kin + 0.5 mg/L NAA with 2.80 shoots per explant. The best results were obtained from 3.10 cm shoots cultured in a medium containing 0.5 mgL-1 Kin in terms of shoot length. 1/1 MS medium with different concentrations of two different auxins (IAA-NAA) (0.25 – 0.5 – 1.0 – 1.5 mg/L) was used for rooting the shoots obtained in vitro. It was observed that root formation did not occur in the cultured explants in the control group and 0.25 mg/L IAA application group, but in other application groups, although there were differences depending on the concentration, root formation was observed. It was determined that NAA concentrations gave better results than IAA concentrations among the auxin varieties used. The best results in terms of both root length and root number were obtained from the explants cultured in medium supplemented with an average of 26.50 roots per shoot and 1.51 cm with 1.5 mg/L NAA. In addition, it was observed that the explants cultured in all treatment groups, including the control group, formed new shoots and continued to develop healthily. Rooted seedlings were transferred to pots with a perlite-peat mixture (1:2), and their adaptation to the soil was successfully (100%).