Shoots Regeneration in Brigitta and Duke Blueberry Cultivars from Different Encapsulated Vegetative Propagules

Synthetic seed technology, an advanced in vitro propagation method, combines the benefits of micropropagation with the practicality of zygotic seeds, offering an efficient solution for the handling, storage, and transportation of plant propagules. This study represents the first investigation of the role of explant type in blueberry encapsulation. In particular, three non-embryogenic propagules (basal node, median node, and shoot tip) were evaluated in the Brigitta and Duke blueberry cultivars. The artificial endosperm consists of Woody Plant Medium (WPM) macro- and micro-nutrients and Murashige and Skoog vitamins at half concentration, inositol (5 g L−1), Indole-3-butyric acid (IBA) (0.005 mg L−1), zeatin (0.25 mg L−1), and sucrose (50 g L−1). Forty-five days after sowing in in vitro conditions, the encapsulated shoot tips showed better results than basal and median nodes in several parameters, including viability, shoot length, and fresh shoot weight, in both cultivars. In both cultivars, none of the encapsulated propagule types developed roots. These results underscore the advantages of using shoot tips in encapsulation technology for blueberries and provide valuable insights for optimizing encapsulation protocols to improve propagation efficiency.