Comparative evaluation of improved and local varieties of finger millet for nutritional traits

Abstract:

The challenge facing finger millet breeders is not new but remains unresolved: every yield gain delivered over the past four decades has come with some erosion of the mineral density and phenolic richness that made the grain valuable in the first place. This research evaluated six improved varieties and six local landraces of finger millet (Eleusine coracana) across three growing seasons (growing seasons 2021, 2022 and 2023) at the Department of Crop Science, Sokoine University of Agriculture, Morogoro, Tanzania. Grain samples were analysed for proximate composition, calcium, iron, zinc, total phenolics, tannin content, phytic acid and in-vitro protein digestibility. Improved varieties yielded 23.0 q ha⁻¹ on average against 13.0 q ha⁻¹ for landraces - a 76.9 percent advantage - but landraces carried 14.4 percent more crude protein (9.00 vs 7.87 g/100 g), 15.2 percent more calcium (417 vs 362 mg/100 g), 31.7 percent more iron (5.4 vs 4.1 mg/100 g) and 41.1 percent more total phenolics (316 vs 224 mg GAE/100 g). In-vitro protein digestibility was higher in improved varieties (68.4 vs 62.7 percent) because landraces also carried 28 percent more tannin. The trade-off between yield and nutritional density is real and cannot be wished away. The data argue for a two-track approach - continued reliance on improved varieties for food security targets, with simultaneous conservation and promotion of nutritionally superior landraces through the National Food Fortification Programme framework.