Comparative evaluation of explants and culture media in the in vitroestablishment of bolivian cacao (Theobroma cacao L.) at the Sapecho Experimental Station

Abstract

The aim was to improve the propagation and conservation of Bolivian national cocoa. This study evaluated the efficiency of explants (staminodes and petals) and culture media for in vitro propagation. The research was conducted at the Biotechnology Laboratory of the Experimental Station of Sapecho, from September 2023 to June 2024. The methodology consisted of selecting cacao flower buds, preparing culture media (M1, M2, and M3) based on Murashige and Skoog, varying components such as coconut water, gibberellic acid, ascorbic acid, and citric acid, followed by disinfection and establishment. The results showed that staminodes had lower contamination (57%) compared to petals (97%). The M1 culture medium, with coconut water, showed the lowest contamination rate (70%); in terms of survival, staminodes cultivated in the M1 medium showed the highest survival rate (41.67%); while for callus formation, staminodes in M1 and M3 media presented better results (40% and 32% respectively), and gibberellic acid in the M2 medium favored callus formation in petals(5%). In conclusion, staminodes are better explants as they show lower contamination and higher survival rates. The M1 culture medium, with coconut water, was the most suitable for callus formation in staminodes. The combination of explant and culture medium significantly influences the success of in vitro cultivation. These findings provide a basis for developing more efficient in vitro propagation protocols for Bolivian national cocoa.