ABSTRACT
Rice breeding in West Africa has been largely skewed toward yield enhancement and stress tolerance. This has led to the variable grain quality of locally produced rice in the region. This study sought to assess variations in the agronomic and grain quality traits of some rice varieties grown in this region, with a view to identifying sources of high grain yield and quality that could serve as potential donors in their breeding programs. Forty-five varieties were grown under irrigated conditions in Benin and Senegal with two trials in each country. There were wide variations in agronomic and grain quality traits among the varieties across the trials. Cluster analysis using paddy yield, head rice yield, and chalkiness revealed that 68% of the total variation could be explained by five varietal groupings. One group comprising seven varieties (Afrihikari, BG90-2, IR64, Sahel 108, WAT311-WAS-B-B-23-7-1, WAT339-TGR-5-2, and WITA 10) had high head rice yield and low chalkiness. Of the varieties in this group, Sahel 108 had the highest paddy yield in three of the four trials. IR64 and Afrihikari had intermediate and low amylose content, respectively, with the rest being high-amylose varieties. Another group of varieties consisting of B6144F-MR-6-0-0, C74, IR31851-96-2-3-2-1, ITA222, Jaya, Sahel 305, WITA 1, and WITA 2 had high paddy yield but poor head rice yield and chalkiness. The use of materials from these two groups of varieties could accelerate breeding for high yielding rice varieties with better grain quality for local production in West Africa.
ABSTRACT
In West Africa, landraces or local varieties of fonio are processed into many products by women using small processing units and marketed locally as well as exported to Europe and the United States. The objective of this study was to evaluate the effect of processing methods, namely parboiling, precooking and roasting on the physico-chemical and functional properties of two mainly preferred fonio landraces (Iporhouwan and Namba) by consumers. Results showed that the physico-chemical characteristics and most functional properties were significantly (P < 0.0001) affected by the processing methods. The lowest brightness (L*) values were obtained for parboiled fonio for the two landraces. However, parboiled fonio presented the best biochemical composition as compared to the dehusked, milled, precooked and roasted fonio samples. The protein contents of parboiled fonio samples were 6.06 % and 7.24 % for Iporhouwan and Namba landraces respectively. The values of peak viscosity, trough viscosity, breakdown, final viscosity and setback, were significantly higher for dehusked and milled fonio than for precooked, parboiled and roasted fonio with respect to both landraces. The milled fonio showed highest peak viscosity (2,668.5 cP) which was similar for the both tested landraces.
