Molecular characterization of Cucumber mosaic virus sub group IB infecting Cavendish banana plants in Ethiopia

Abstract

Banana is the major fruit crop produced in Ethiopia. Since Cucumber mosaic virus (CMV) is one of the most devastating plant viruses infecting banana, the present study was undertaken to survey and identify CMV strains infecting banana plants in Ethiopia. Dot immune-binding assay (DIBA) and reverse transcription-polymerase chain reaction (RT-PCR) revealed the presence of CMV in all of the symptomatic samples tested. The results of sequence and phylogenetic analysis revealed that the isolate under study was a CMV isolate from the IB subgroup. Multiple sequence alignment revealed a three nucleotide sequence variation that could be used to distinguish CMV subgroups. Selection pressure analysis showed the CMV-RNA1 region undergoing positive selection pressure. Tajima`s test of neutrality revealed a positive value of 0.86468 indicating CMV population contraction. To the best of our knowledge, this is the first report and molecular characterization of CMV IB subgroup isolate infecting banana plants in Ethiopia.