Abstract :
[en] Banana mild mosaic virus (BanMMV) (Betaflexiviridae, Quinvirinae, unassigned species) is
a filamentous virus belonging to the Betaflexiviridae family. It infects Musa spp. with a very wide
geographic distribution. The genome variability of plant viruses, including the members of the
Betaflexiviridae family, makes their molecular detection by specific primers particularly challenging.
During routine indexing of the Musa germplasm accessions, a discrepancy was observed between
electron microscopy and immunocapture (IC) reverse transcription (RT) polymerase chain reaction
(PCR) test results for one asymptomatic accession. Filamentous viral particles were observed while
molecular tests failed to amplify any fragment. The accession underwent high-throughput sequencing
and two complete genomes of BanMMV with 75.3% of identity were assembled. Based on these
sequences and on the 54 coat protein sequences available from GenBank, a new forward primer,
named BanMMV CP9, compatible with Poty1, an oligodT reverse primer already used in diagnostics,
was designed. A retrospective analysis of 110 different germplasm accessions from diverse origins
was conducted, comparing BanMMCP2 and BanMMV CP9 primers. Of these 110 accessions, 16 tested
positive with both BanMMCP2 and BanMMV CP9, 3 were positive with only BanMMCP2 and 2 tested
positive with only BanMMV CP9. Otherwise, 89 were negative with the two primers and free of
flexuous virions. Sanger sequencing was performed from purified PCR products in order to confirm
the amplification of the BanMMV sequence for the five accessions with contrasting results. It is highly
recommended to use the two primers successively to improve the inclusiveness of the protocol.
Scopus citations®
without self-citations
3