Sorghum (Sorghum bicolor L.) serves as an alternative food crop to rice in addressing food shortages and malnutrition. Breeding programs aimed at increasing yield and biofortification in sorghum require accessions with superior agronomic traits, as well as high iron (Fe) and zinc (Zn) contents. This study sought to assess the variation in agronomic characteristics and Fe and Zn contents among Indonesian sorghum germplasm. The genetic materials evaluated consisted of 20 IPB breeding lines, six introduced accessions, five local varieties, and seven national varieties arranged in an augmented design. The observed traits included agronomic characters and grain micronutrient contents (Fe and Zn). Leaf number, green leaf index, days to flowering and maturity, panicle weight, and thousand-seed weight exhibited high heritability. Fe content showed the highest broad-sense heritability, whereas Zn content displayed relatively low variation and heritability. All observed traits, except green leaf index and panicle length, revealed a positive correlation with seed weight per panicle. Fe and Zn contents indicated nonsignificant correlations with panicle weight and seed weight per panicle. Based on mean values and heritability estimates, promising germplasm for further development includes national varieties for yield improvement and local varieties for biofortification purposes.

Keywords: Sorghum (S. bicolor L.), biofortification, Fe and Zn, germplasm, Pearson’s correlation, XRF

Key findings: Among 38 Indonesian sorghum (S. bicolor L.) germplasm evaluated, the local variety Pulut-3 exhibited the highest seed iron (Fe) content, reaching 54.5 ppm. This trait shows very high broad-sense heritability and a significant positive correlation with seed zinc (Zn) content. This genotype holds strong potential for further biofortification efforts aimed at enhancing micronutrient concentrations.