Genetic diversity and trait associations in biofortified short-duration sweet potato (Ipomoea Batatas L.) genotypes
摘要
Sweet potato (Ipomoea batatas L.) is a nutrient-dense crop rich in carbohydrates, vitamins A and C, and dietary fiber, with broad adaptability. Biofortified cultivars containing high beta-carotene (> 8 mg/100 g) and anthocyanins (> 25 mg/100 g) are limited. This study aimed to evaluate genetic variability, trait associations, and yield performance among twenty biofortified short-duration sweet potato genotypes.
MethodsGenotypes were evaluated for morphological, physiological, nutritional, and yield traits in a randomized complete block design with three replications. Data were analyzed using ANOVA, correlation, PCA, cluster analysis, and genetic parameter estimation.
ResultsSignificant genotypic differences (p < 0.001) were observed for the most traits, including number and mass of total and economic tuberous roots. The greatest yield was recorded in genotype BAU Sweetpotato-5 (44.8 t ha⁻¹), which was followed by G-54 (27.1 t ha⁻¹) and Amtoli-3 (17.3 t ha⁻¹). Yield was positively correlated with root number and mass. A total of 79% of variation was described by the first five components, according to principal component analysis (PCA), with PC1 and PC2 accounting for 47%. The principal component (PC) scores of genotypes were separated largely by higher, negative coefficients of number and mass of both total and economic root traits, nutritional traits — % of glucose, fructose, sucrose and lower, negative coefficients of two physiological traits —leaf vapor pressure (LVP), vapor pressure deficit (VPD); and number of leaves per vine. Cluster analysis grouped genotypes into four distinct clusters with cluster II representing high-yielding genotypes and cluster I representing moderately carotene-enriched genotypes. High heritability and genetic advance of mean for yield (89% and 130%), economic root mass, (87% and 135.6%) leaf area (97.6% and75%, respectively) indicate their strong potential for selection.
ConclusionThe study revealed substantial genetic variability among the evaluated sweetpotato genotypes, providing valuable information for future breeding, genetic studies, and conservation efforts.