Evaluation of Grains of Cowpea Magic Population Lines For Protein And Iron Concentration

Abstract

Cowpea (Vigna unguiculata (L.) Walp is an annual legume grown in SSA. It’s grains, leaves, and immature pods are important sources of plant-based proteins and essential nutrients for human health. Consumers can greatly benefit from the development and deployment of cowpea cultivars with increased nutritional content, particularly in SSA where the cost of meat is expensive in relation to income. As a first step to contribute to the improvement of the nutritional composition of cowpea grain genotypes, cowpea grains of a total of one hundred and sixty-six cowpea genotypes comprising of;  one hundred and fifty cowpea MAGIC (multi-parent advanced generation inter-cross) population lines,  five founder parents of cowpea MAGIC population, six released varieties and five landraces were obtained from MaRCCI gene bank and quantified for protein and iron concentration using the micro-Kjeldahl and thiocyanate colorimetry methods respectively at the Animal Nutrition laboratory Makerere University. The data  was subjected to ANOVA and Hierarchical clustering method using R software. ANOVA Results obtained showed highly significant genotypic differences (P<0.001) for protein and iron concentration among the cowpea genotypes. The clustering method distributed the cowpea genotypes into four groups. Group G3  revealed the highest mean protein concentration of 21.32% and the lowest iron concentration of 26.08mg/kg. Group G4 displayed low mean protein concentration of 21.11% and highest mean iron concentration of 54.45mg/kg. Several of the genotypes in groups G3 and G4 would be useful genetic resources in breeding programs designed to develop cowpea varieties that are nutrient-dense, contributing to combat nutrient deficiencies plaguing SSA.