Yam (Dioscorea spp.) is an important food source for a large part of the population in tropical regions. However, yam is susceptible to a range of serious and debilitating diseases including viruses. The application of water-dissolved ozone (1.5 ppm for 10 min) allowed to get potyvirus-free in vitro yam plants, with an efficiency rate statistically similar to the electrotherapy (63.5% and 62.5%, respectively). Besides, the application of ozone stimulated the growth of the in vitro-produced plants, which represent an important advantage over other sanitation methods used during the Biotechnology Seed Production program of yam in Cuba.

This study analyzed the genetic progress of sweet potato (Ipomoea batatas) breeding in Cuba over the past 50 years by field trials comparing traditional and improved varieties. Improved varieties significantly outperformed traditional ones in tuberous root yield, with an accumulated genetic gain of 0.20–0.37 t ha⁻¹ per year, translating to a 256% yield increase. Improved genotypes also exhibited enhanced pest tolerance: lower weevil (Cylas formicarius) infestation and reduced nematode (Meloidogyne incognita) reproduction rates. For viral diseases, 60% of improved varieties showed incidence rates below 10%, compared with 90% of traditional varieties exceeding this threshold. Under drought conditions, improved varieties showed tolerance, with Stress Susceptibility Indices (SSIs) of less than 0.8, while the traditional varieties were more susceptible (SSI > 1). Phenotypic stability analysis via GGE biplot confirmed the superior yield and adaptability of improved varieties across environments. These advances underscore the critical role of sweet potatoes breeding in Cuba, with improvements in yield, quality and resistance to biotic and abiotic stress, contributing to strengthening climate resilience and food security.

Potyvirus diseases are one of the main challenges facing the production of yam (Dioscorea spp.). The objective of this study was to identify the potyviruses present in the Dioscorea spp. germplasm collection at Instituto de Investigaciones de Viandas Tropicales (INIVIT) to establish methodologies for the characterization of the associated diseases. For this purpose, immunochemical and molecular methods were used to identify the potyviruses present. The symptomatology of Dioscorea spp. at INIVIT’s germplasm collection was described. In addition, the severity and incidence in the germplasm collection and production areas were evaluated. As a result, the first report of yam mosaic virus (Potyvirus yamtesselati) and yam mild mosaic virus (Potyvirus yamplacidum) in Cuba is presented. The existence of resistant, tolerant, and susceptible cultivars to potyvirus-associated diseases in the germplasm collection was detected, and the incidence of these diseases was higher than 64% in the production areas evaluated. This study represents a step forward in the establishment of certification programs for propagating material of Dioscorea spp. in Cuba.

Taro is a food source for many people in tropical countries. The use of biotechnological techniques for seed production is an alternative that allows obtaining propagation material of higher phytosanitary quality. During the taro in vitro propagation it is of great importance to increase the efficiency of the protocols that are affected mainly by the incidence of microbial contamination and low multiplication coefficients. At the initiation stage, 100% of taro apical meristems sprouted with the immersion in water-dissolved ozone at 2 ppm for 15 min. Furthermore, the microbial contamination was eliminated and the explants showed better quality, increasing the multiplication coefficient in the subsequent subcultures. The disinfection strategy applied allowed to rise the number of taro explants by more than three times, increasing the economic efficiency of the process.

A breeding program was established in Cuba using 19 full-sib families of sweetpotato (Ipomoea batatas [L.] Lam.) introduced as botanical seed from the International Potato Center (CIP). The objective was to develop biofortified cultivars combining high yield, phenotypic stability, and high β-carotene content under tropical conditions. The program followed a four-stage pipeline: (1) F₁ population establishment and visual selection (1732 plants) for morphological and pest/disease resistance traits; (2) initial clonal evaluation (C1) of 103 genotypes, estimation of genetic parameters, and multi-trait selection; (3) advanced evaluation of 19 elite genotypes, including analysis of genetic correlations and stability across two seasons; and (4) multi-environment trials (13 locations) with AMMI, GGE biplot, and MGIDI analyses. General and specific combining abilities were estimated, and broad-sense heritability (H²) was calculated. Three new biofortified cultivars ‘INICIP Dorado-4’, ‘INICIP B-30’, and ‘INICIP B-60’ were selected. These combine high yields, high β-carotene content, and distinct profiles for specific agronomic niches, with a total cumulative phenotypic gain of +352.8% achieved over four selection stages within a three-year period. This pipeline constitutes a replicable model for resource-constrained regions, demonstrating the potential of CIP germplasm to drive sweetpotato biofortification.