Genetic diversity and population structure of Urochloa grass accessions from Tanzania using simple sequence repeat (SSR) markers

dc.creatorKuwi, S.O.
dc.creatorKyallo, Martina M.
dc.creatorMutai Collins, K.
dc.creatorMwilawa, A.
dc.creatorHanson, Jean
dc.creatorDjikeng, Appolinaire
dc.creatorGhimire, Sita R.
dc.date2018-09
dc.date2018-09-07T13:20:50Z
dc.date2018-09-07T13:20:50Z
dc.date.accessioned2026-06-27T17:04:17Z
dc.descriptionUrochloa (syn.—Brachiaria s.s.) is one of the most important tropical forages that transformed livestock industries in Australia and South America. Farmers in Africa are increasingly interested in growing Urochloa to support the burgeoning livestock business, but the lack of cultivars adapted to African environments has been a major challenge. Therefore, this study examines genetic diversity of Tanzanian Urochloa accessions to provide essential information for establishing a Urochloa breeding program in Africa. A total of 36 historical Urochloa accessions initially collected from Tanzania in 1985 were analyzed for genetic variation using 24 SSR markers along with six South American commercial cultivars. These markers detected 407 alleles in the 36 Tanzania accessions and 6 commercial cultivars. Markers were highly informative with an average polymorphic information content of 0.79. The analysis of molecular variance revealed high genetic variation within individual accessions in a species (92%), fixation index of 0.05 and gene flow estimate of 4.77 showed a low genetic differentiation and a high level of gene flow among populations. An unweighted neighbor-joining tree grouped the 36 accessions and six commercial cultivars into three main clusters. The clustering of test accessions did not follow geographical origin. Similarly, population structure analysis grouped the 42 tested genotypes into three major gene pools. The results showed the Urochloa brizantha (A. Rich.) Stapf population has the highest genetic diversity (I = 0.94) with high utility in the Urochloa breeding and conservation program. As the Urochloa accessions analyzed in this study represented only 3 of 31 regions of Tanzania, further collection and characterization of materials from wider geographical areas are necessary to comprehend the whole Urochloa diversity in Tanzania.
dc.identifierhttps://hdl.handle.net/10568/97092
dc.identifier.urihttp://hdl.handle.net/123456789/141359
dc.languageen
dc.publisherSpringer
dc.rightsOpen Access
dc.sourceKuwi, S.O., Kyalo, M., Mutai, C.K., Mwilawa, A., Hanson, J., Djikeng, A. and Ghimire, S.R. 2018. Genetic diversity and population structure of Urochloa grass accessions from Tanzania using simple sequence repeat (SSR) markers. Brazilian Journal of Botany 41(3):699–709.
dc.subjectcrops
dc.subjectforage
dc.subjectmixed farming
dc.subjectlivestock
dc.titleGenetic diversity and population structure of Urochloa grass accessions from Tanzania using simple sequence repeat (SSR) markers
dc.typeJournal Article

Archivos