REGENERATION OF Sechium edule FROM NODAL EXPLANTS THROUGH SYNTHETIC SEEDS

This is the first attempt established for the plant regeneration from the alginate-encapsulated nodal explants obtained from in vitro raised shoots of Sechium edule for large scale clonal propagation and short-term conservation using encapsulation technology. Synthetic seeds were prepared by encapsulating in vitro nodes using sodium alginate of 2.0, 2.5, 3.0, 3.5 and 4.0% (w/v) with 25, 50, 75 and 100 mM calcium chloride. The ideal bead complexation and formation was attained at 3.5% sodium alginate prepared in MS salts and vitamins with 100 mM calcium chloride. The potential of synthetic seeds able to germinate as true seeds was evaluated (97.76%) effectively on MS medium supplemented with 2 mM BAP + 0.5  mM IBA. The synthetic seeds were stored at 4 ± 2°C and 21 ± 2°C for the duration of 0, 15, 30, 45 and 60 days to evaluate the comparative plant revival, seed viability, and conversion potential of synthetic seeds. Results suggested that effective storage duration evaluated was 30 days, with a regeneration rate of 62.16% at 4°C without compromising the quality of the entrapped explants. Plantlets grown from encapsulated nodes were transferred in earthen pots and successfully hardened, acclimatized and transplanted to field with 85% survival rate. RAPD and ISSR band patterns obtained were monomorphic and similar to the mother plant, thus validates the true-to-type genotypes among the Sechium edule clones.