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.
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.