Genetic Diversity and Phylogenetic Relationships of Three Viruses Infecting Yam (Dioscorea Spp.) in Guinea Savanna Zone of Nigeria
Asala, S.W; Banwo O.O.

Abstract
Yam mosaic virus (YMV), Yam mild mottle virus (YMMV) and Dioscorea alata bacilliform virus (DaBV) are important viruses infecting different species of yam in Nigeria. Only YMV has been well characterised in sub-Saharan Africa. The aim of this study was to characterise the three viruses in Guinea Savanna zone of Nigeria and compare them with counterpart viruses of yam in other parts of the world. Purified nucleic acid products prepared in the Virology and Molecular Diagnostic Laboratory of the International Institute of Tropical Agriculture, Ibadan, Nigeria were shipped to the Molecular Laboratory, Iowa State University, United States of America for sequencing. Twenty-two (22) sequence data of virus isolates from the two locations in Nigeria were evaluated. Sequences of counterpart viruses were obtained from GenBank. YMMV in isolates from Dioscorea alata from the two locations were 100% and 99% related to isolates (D. rotundata) from Ghana and Guadeloupe, respectively. YMVs in isolates from Gbakumo and Dan-anachia (Dioscorea rotundata) from the two locations were 81% and 65% related to counterpart isolates from Cameroun and Cote d’Ivoire, respectively. The presence of strong geographical clustering and relationship between viruses from isolates in the study and other counterparts suggests regional and widespread distribution of these viruses.

Full Text: PDF     DOI: 10.15640/jaes.v9n2a8