Résumé
The complete genome sequence of Dioscorea bacilliform TR virus (DBTRV) was determined. The closest relatives of DBTRV are Dioscorea bacilliform AL virus (DBALV) and Dioscorea bacilliform RT virus 1 (DBRTV1). Specific primers were designed and used to determine the prevalence of DBTRV in a yam germplasm collection. It was found that this virus infects
Dioscorea alata
and
D. trifida
plants in Guadeloupe and French Guyana. DTRBV was not detected in any of the tested
D. cayenensis-rotundata
accessions.
In silico
analysis provided evidence for the presence of DBTRV-like endogenous sequences in the genome of
D. cayenensis-rotundata
, pointing to a possible role of these sequences in antiviral defense.