Assessing iron and zinc micronutrient content of mungbean genotypes: Implications for nutritional quality improvement in Tanzania

Mungbean (Vigna radiata) is a globally significant legume, valued for its iron and zinc content, essential micronutrients that help reduce deficiencies in human populations. Despite its importance, the genetic and nutritional diversity of mungbean genotypes in Tanzania remains underexplored, particularly regarding micronutrient content. This study aimed at analyzing the seed micronutrient (iron and zinc) content among 35 mungbean genotypes from Tanzania, characterized by diverse agro-ecological zones. The field experiment was conducted during the 2023/2024 season at two locations, Miwaleni (Kilimanjaro) and SUA (Morogoro), using a Randomized Complete Block Design (RCBD) with three replications. Atomic Absorption Spectroscopy (AAS) was used to determine iron and zinc concentrations in the seeds, revealing significant variation (p ≤ 0.05) among genotypes. Soil analysis at Miwaleni revealed neutral pH (6.97) with 3.2 ppm zinc and 156.7 ppm iron, while SUA soil had slightly acidic pH (6.17) with 4.2 ppm zinc and 88.7 ppm iron. Mungbean grains grown at Miwaleni exhibited higher iron content (92.2 ppm) compared to SUA (90.1 ppm), while zinc content was higher in grains from SUA (32.5 ppm) than Miwaleni (28.1 ppm). Among the genotypes, M10 had the highest iron content (98.3 ppm), and M7 had the highest zinc content (42.9 ppm), while M1 and M31 showed the lowest concentrations for these respective micronutrients. The study highlights significant variability in micronutrient content, suggesting potential for breeding programs to enhance nutritional quality. Genotypes M10 and M7 emerged as promising candidates for biofortification, offering potential avenues for improving micronutrient intake in populations reliant on mungbeans as a dietary staple. These findings contribute to breeding strategies and agricultural practices that could help combat micronutrient deficiencies in Tanzania, promoting better health outcomes for local communities.