Mineral micronutrient density in local cereals sampled from Bungoma, Maseno and Kibwezi areas

Abstract

Cereals constitute a food staple in the African bread (Ugali) form. Overdependence on maize as a predominant staple is partly blamed on the constricting indigenous cereal phyto-diversity. Strategies rekindling interest in their restoration remain few and disconnected. Thus, the objectives were to: (1) search for micronutrient density information among accessions of sorghum, finger millet, pearl millet and maize on the basis of 'where-they-were-as they-were' (free-call diversity); (2) determine micronutrient densities linked to eco-nutrametric variation for distinguishing differences among accessions. The accessions were collected in 2003/04 from the Bungoma-Maseno-Kibwezi (BMK) phyto-regions and subjected to Energy Dispersive X-ray Fluorescence (XRF) analysis. A nested design was used for sampling in which the cereal species were nested within sites and sites nested within phyto-regions. For each accession with its soil, a gamut of element concentrations was XRF-generated. The data were subjected to a Clustered Bar Graphing (CBG) test for identifying variation-picking element(s). By CBG test, a given element's concentration data range was placed along the X-axis upon which species/accessions' density categories along the Y-axis were graphed as series in rows giving way to density variation comparisons. Where no such density variations were visible, the element was disregarded as non-variation-picking. The CBG test revealed that all accessions were 'imperfect' in that none of them had the gamut elements (density as subject score) inall-top or in-all-low density, i.e. none of the accessions scored high 'As' or low 'Cs' in every elemental density case. This implied that a phenotypic characterization as a whole would have required describing an accession in as different (number of) ways as the number of the variation-picking elements included. A soil-to-plant mineral flow (elemental uptake-ability or EU) was further calculated as a single value [plant ppm]/[soil] x 100. In sorghum the EUs were as follows: 2.4% for Fe (in accession tC74), 211% for Zn (in tC65), 332% for Cu (in tC36) and 408% for K in (tC70). The CBG test among the cereal accessions is invaluable for distinguishing within and between accessions in respect of their single element uptake-ability. A single nutrametric value (NMV) or grade, on the other hand, appears useful in describing a nutrametric phenotypic variant as it bypasses the genotype-environment interaction dilemma. Its robustness is its ability to distinguish various phenotypic mineral micronutrient diversity grading and offers opportunities for mineral micronutrient mapping across phyto-regions.

Investigating viability of the premium influenced land agro-usage structure for production of African leafy vegetables in Vihiga and Jinja

“…Recent studies have shown that ALV's such as Curcubita maxima, Amaranth spp., Cleome gynandra and Solanum nigram are mineral micro-nutrient (MiMi) richer than cereal crops such as maize and sorghum (Akundabweni et al, 2010). In fact, almost all the leafy vegetables are good sources of micronutrients including iron and calcium as well as vitamins A, B complex, C and E. For example, Amaranth contains a multiple of these nutrients compared to Brassicca oleracea (IPGRI, 2003;Abukutsa-Onyango, 2007).…”