Somatic embryogenesis in Abies nebrodensis, an endangered Sicilian fir

Abstract

The critically endangered Sicilian fir ( Abies nebrodensis ) (Lojac) Mattei remains alarmingly close to extinction, even after the initially encouraging results previously obtained by the EU LIFE (European LIFE program) funded project in over ten years. Thus, an efficient protocol for in vitro propagation, seed and cryo-banks establishment would be needed to protect and preserve such species. Therefore, s eeds from Abies adult trees were collected and callus was initiated from both zygotic immature and mature embryos, testing different culture media. Embryogenic (EC) and non-embryogenic (NEC) callus were successfully induced from mature embryos with variable frequencies (0% - 40%) in SH (Schenk and Hilderbrandt) medium, supplemented with 1 mg L −1 6benzylaminopurine, 500 mg L −1 glutamine, 1 g L −1 casein, and 1 g L −1 myo-inositol. The effect of donor tree was observed, and callus initiation rate of up to 40% was observed in the mature zygotic embryos issued from donor tree with identification number (IN) 8. The immature embryos remained unresponsive. Maturation of cell lines from trees with IN7, IN8, IN10 and IN 21 was successfully achieved with 10 mg L -1 abscisic acid and polyethylene glycol (PEG-4000, 8%).

Current status of the cryopreservation of embryogenic material of woody species

“…Since the first reports on SE (Chalupa, 1985;Hakman et al, 1985), this propagation method has been mainly developed in species with economical relevance. However, in the last years it has also been developed for endangered species (Ahn and Choi, 2017;Ahn et al, 2019;Maruyama and Hosoi, 2019;Jouini et al, 2023).…”