In vitro propagation of Fritillaria pontica Wahlenb.

The present research aimed to develop an in vitro propagation protocol for Fritillaria pontica, a geophyte naturally distributed in Southeastern Europe and Northwestern Türkiye, by testing different temperature regimes and exogenous plant growth regulator treatments (PGR). Thidiazuron (TDZ) treatment at 2.0 mg L− 1, applied during a repeated cycle of short-term cold treatment (RSCT), induced the highest seed germination rate (60%) and shoot production (0.6 shoot per seed). Root formation was minimal under PGR treatments, regardless of the incubation temperature regime. 6-benzylaminopurine (BAP) at 2.0 mg L− 1 induced the highest bulblet production per seed (0.26 bulblet per seed) and most elongated shoots (1.46 cm per seed) treated with prolonged-term cold (PCT). The calli around the seedlings were cultured on the same medium enriched with kinetin (KIN) for organ induction for 2 and 6 months. Control medium induced the highest caulogenesis response at the end of both periods. Bulblets were also treated with TDZ, indole-3-butyric acid (IBA), and 1-naphthaleneacetic acid (NAA) for the same periods as calli. The control medium yielded the highest shoot and root production from bulblet cultures after 2 months. TDZ and NAA at 0.5 mg L− 1 yielded the highest shoot and root production, respectively, after 6 months. The shoots derived through indirect organogenesis responded to IBA treatments only during a 6-month incubation. IBA at 2.0 mg L− 1 yielded the highest rhizogenic response (3.13 roots per shoot at 1.51 cm). The methodology developed in our study would contribute to conservation studies on the Fritillaria species. A gradually increasing temperature regime and thidiazuron at a higher concentration increase germination and organ development, while certain kinetin and indole-3-butyric acid treatments trigger callogenesis or rooting in Fritillaria pontica.