Indirect auxiliary organogenesis of Fraxinus excelsior L. as a tool for ash dieback control

Berlin

2024

143-156

323-344

e-journal

200211705

Keywords: European ash · Primary explants · Zygotic embryos micropropagation · Callus cultures · Seedlings regeneration
The existence of European ash (Fraxinus excelsior L.) is threatened by fungus-induced ash dieback. It is essential to find effective methods to multiply ash genotypes resistant to ash dieback while preserving the genetic diversity of these tree populations. In this paper the efficient method for production of European ash seedlings using indirect auxiliary organogenesis with multi-factor analysis of its effectiveness is presented. Procedures for a dormancy breaking treatment of seeds and effective disinfection of F. excelsior primary explants, as well as appropriate composition of the culture media taking into account impact of growth regulators and physiological gradient on the micropropagation efficiency were developed. As primary explant for micropropagation of F. excelsior, leaf buds, megagametophytes and zygotic embryos were tested. The best-performing type of primary explant for micropropagation of European ash proved to be zygotic embryos, which were successfully used to regenerate seedlings via indirect auxiliary organogenesis. No statistically significant impact of population origin of F. excelsior explant donor trees was observed on the effectiveness of callus initiation.