First Report of Dioscorea Bacilliform Virus, a Badnavirus Infecting Yam in Burkina Faso

In Burkina Faso, yam plays an important role in food security and improving people's incomes. However, the sector is struggling to develop due to a number of constraints, including significant viral pressure. The Dioscorea bacilliform virus (DBV), prevalent in yam-growing areas of the West African region, is causing huge production losses. A survey followed by sample collection was carried out in yam fields in the Centre-Ouest and Cascades regions. A total of 32 samples were collected, of which 26 were symptomatic and 6 asymptomatic. The samples collected were subjected to biological, serological and molecular diagnosis. The study revealed the presence of DBV in all symptomatic samples tested. No asymptomatic samples were positive. Comparison of the sequences of the reverse transcriptase/ribonuclease H (RT/RNase H) region of the samples collected with those in the GenBank database confirmed the presence of DBV, with similarity rates ranging from 97.73% to 99.02%. Our work has thus made it possible to describe for the first time a new virus infecting yam in Burkina Faso. Studies are now required to generate epidemiological data on the virus and to search for resistance genes through varietal screening.