Short-Term Conservation of Juglans regia L. via Synthetic Seed Technology

Abstract

Juglans regia L. is a crucial species as a forest tree and for its nutritional and medicinal values. It is also included in the list of endangered species in Albania and thus, there is a need to find methodologies to ensure its rapid regeneration and ex situ conservation. This research, investigated the regeneration of plantlets from synthetic seeds containing shoot tips of four native walnut varieties: ‘Përmet’, ‘Korçë’, ‘Peshkopi’, and ‘Tropojë’. First, in vitro-derived shoot tips from walnut seedlings are encapsulated using sodium alginate. After that, the regeneration potential of the encapsulated shoot tips and the influence of incubation conditions are evaluated. The synthetic seeds were incubated at either 25 °C or 8 °C, with and without dehydration treatment, in 0.5 M sucrose solution for 3 h. The synthetic seeds in both temperature regimes (25 °C and 8 °C) develop plantlets and provid conservation potential without the need for subcultures for 4 and 3.5 months, respectively. Furthermore, all walnut varieties incubated in these conditions achiev a high regeneration rates.