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Two Outstanding Oryza glaberrima (2n = 24, AA) varieties TOG5681 and TOG5674 were used as male donor parents with IR64, the high-yielding improved Asian rice variety used as recurrent female parent by the International Rice Research Institute (IRRI) to develop 18 BC 3 F 1 interspecific lowland rice progenies. The proportion of parental genomic contribution and the extent of genetic differences among these lines were assessing using 36 microsatellites markers. The average genomic contribution of the donor TOG5681 and that of the recurrent IR64 within their 12 interspecific lines derived from IR64xTOG5681 cross were estimated to 13.2% and 79.8% respectively. Using 33 out of the 36 SSR markers, the average genome introgression rate of TOG5674 and that of IR64 within their 6 progenies were estimated to 8.7% and 85.5% respectively. In addition, heterozygosity and non-parental alleles were also identified. Clustering analysis technique using NTSYS classified the progenies into six groups and group five is closely related to IR 64.

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In an early yellow root cassava study in 2003 to 2004, we investigated agronomic performance of pro Vitamin A (yellow fleshed) cassava genotypes in three locations in Nigeria (Ibadan, Mokwa, and Onne). Twenty-two clones and three checks were evaluated. A randomized complete block design was used with four replications. Characteristics showing significant differences among genotypes across all locations included sprouting, vigor, harvest index, root size, storage root yield, dry matter content and fiber content. Plant height, root mealiness and taste were different in only selected locations. Six clones showed stable performance across locations including IITA TMS I011413, IITA TMS I011442, IITA TMS I011663, IITA TMS I982132, IITA TMS I011277 and IITA TMS I011235. Clones IITA TMS I940330 showed the highest dry matter content of 38%. All clones exhibited good resistant to cassava mosaic disease, cassava bacterial blight, cassava green mite, and cassava anthracnose disease. These genotypes ranged in total carotenoid content from 3.4 to 8.2 µg/g fresh weight. In terms of yield, the best clones were IITA TMS I011368 (26 t/ha), IITA TMS I011663 (22 t/ha) and IITA TMS I982132 (25 t/ha). For gari yield clone IITA, TMS I011649 gave 25%, IITA TMS I940330 gave 23%, and IITA TMS I9001554 gave 23%. They were better than the best check IITA TMS I30572, with 22% gari yield. This study showed the potential for biofortification of cassava as a valid strategy to approach the problem of micronutritient deficiencies of the population in the region where cassava is a staple food.

Rice cultivation in Africa suffers from various biotic and abiotic constraints. The African rice, Oryza glaberrima, is a potential source of useful genes for resistance to a range of these stresses. The development of interspecific varieties based on crosses between the high yielding cultivated Asian rice species (Oryza sativa) and O. glaberrima showed some gaps in the resistance compared to O. glaberrima. In order to valorize its genetic potential, intraspecific lines were developed using three O. glaberrima lines Tog5681, Tog5672 and Tog7291 as parents. Phenotypic evaluation of the progeny (total of 55 F 6 lines) and checks (O. glaberrima and O. sativa) using 18 quantitative characters, showed a higher degree of variation in plant height, leaf dimensions, panicle fertility and grain weight. Based on the discriminating characters proposed here for further exploitation, intraspecific lines were grouped into five clusters, two of which (G4 and G5) contained the best lines for vegetative (G4) and productive (G5) characters.