UCUDIRBrowsing by Author "Egwang, T.G."

Now showing 1 - 1 of 1

Assessment of cassava diversity in Uganda using SSR markers
(2004) Kizito, Elizabeth B.; Castelblanco, W.; Omara, J.; Bua, A.; Egwang, T.G.; Fregene, M.; Gullberg, U.
The genetic diversity and differentiation of 272 cassava landrace accessions collected in Uganda is assessed in this study. In addition to this, 20 Tanzanian material was included from a previous study of diversity in Tanzania, 20 material from the Ghanaian germplasm bank, 20 material from Guatemala and 18 from holdings at CIAT and IITA to represent the core collection from Latin America. All together 9 groups or samples, based on country of origin, were created to study genetic diversity and differentiation within each country and among countries. Using simple sequence repeat (SSR) markers, variation in allele frequency at many unlinked loci was used to estimate the parameters of genetic diversity and differentiation, and to estimate the strengths of various forces shaping them. SSR data was analyzed by GENSURVEY (Vekemans & Lefebvre,1997), FSTAT 2.9 (Goudet, 1995) and NTSYS-PC(Rohlf, 1993). Results affirm a genetic divergence between African and Latin American accessions. They also show a high genetic diversity and a low differentiation in the Ugandan accession. There is a substantial role played by the cassava mosaic disease (CMD) on cassava genetic constitution in respective districts.