Técnica de encapsulamiento de embriones en alginato de sodio para la germinación de: Vasconcellea cundinamarcensis y Hyeronima macrocarpa, provincia Azuay

Abstract

The technology of encapsulating embryos in sodium alginate (called synthetic or artificial seed) is a successful alternative for the propagation, multiplication and conservation of species. This study was developed in the In Vitro Plant Propagation Laboratory, Seed Laboratory, and greenhouse at the Faculty of Agricultural Sciences of the University of Cuenca, our main objective of evaluating the technique of encapsulation of zygotic embryos of two ecologically and socio-economically important species: Vasconcellea cundinamarcensis (chamburo) and Hyeronima macrocarpa (motilón) and their response in germination and conservation; for this, zygotic embryos were extracted from seeds in physiological maturity and deposited in 4% sodium alginate, one by one the embryos were deposited in a calcium chloride complexing agent in two concentrations of 50mM and 75mM and in two times of immersion 10 and 30 minutes in order to generate a cover that fulfills the function of nourish and protect to facilitate germination. After this, the effect of these variables on the viability of the encapsulated embryos was evaluated, at different storage times 0, 20 and 40 days in the germinating chamber and greenhouse environments. The highest germination values for Vasconcellea cundinamarcensis was the T4 treatment (4% alginate 75mM of CaCl2 30min) with 31.46%, while for Hyeronima macrocarpa in T4 (4% alginate 75mM of CaCl2 30min) 33.30%. Although there were no significant differences in the different treatments in this species. Synthetic seeds were stored for 0, 20, 40 days at 4 and 25 degrees Celsius and then brought to greenhouse and germinating chamber conditions for evaluation. Better germination was observed in greenhouse conditions than in germinating chamber conditions. Regarding the days of storage, Vasconcellea cundinamarcensis showed the germination percentage at (0 days) with 28, 38% when the embryo was encapsulated directly in the greenhouse, likewise for the species Hyeronima macrocarpa with a percentage of 51, 34%. Better development of seedlings from encapsulated embryos stored for 40 days at 25 °C and then planted in the greenhouse was obtained. The results obtained are very useful as they constitute protocols applicable and adapted to forest species that can be conserved and propagated massively.