Le centre de ressources biologiques de Guadeloupe: (Reportage d'ATV Guadeloupe diffusé le 11/1/2016)

(résumé de la chaîne TV) MATERIEL VEGETAL DE GUADELOUPE Il existe près de 450 variétés de bananes, 500 d'ignames en Guadeloupe.... Des variétés qui sont collectionnées au Centre de ressources Biologique tropicale depuis 2010. L'objectif des chercheurs de l' INRA et du CIRAD: constituer une mémoire végétale à la disposition des agriculteurs et des chercheurs du monde entier. Reportage ATV Guadeloupe, diffusé le 11 janvier 201

Patterns of aggressiveness of Colletotrichum gloeosporioides strains causing anthracnose on Water Yams (Dioscorea alata)

International audienc

The genome sequence of Dioscorea bacilliform TR virus, a member of the genus <em>Badnavirus</em> infecting <em>Dioscorea</em> spp., sheds light on the possible function of endogenous <em>Dioscorea</em> bacilliform viruses

First Online: 21 October 2016International audienceThe 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

Molecular Viral Diagnosis and Sanitation of Yam Genetic Resources: Implications for Safe Yam Germplasm Exchange

Yam (Dioscorea spp.) is an important crop in tropical and subtropical regions. Many viruses have been recently identified in yam, hampering genetic conservation and safe international exchanges of yam germplasm. We report on the implementation of reliable and cost-effective PCR-based detection tools targeting eight different yam-infecting viruses. Viral indexing of the in vitro yam collection maintained by the Biological Resources Center for Tropical Plants (BRC-TP) in Guadeloupe (French West Indies) unveiled a high prevalence of potyviruses, badnaviruses, Dioscorea mosaic associated virus (DMaV) and yam asymptomatic virus 1 (YaV1) and a high level of coinfections. Infected yam accessions were subjected to a combination of thermotherapy and meristem culture. Sanitation levels were monitored using PCR-based and high-throughput sequencing-based diagnosis, confirming the efficacy and reliability of PCR-based detection tools. Sanitation rates were highly variable depending on viruses. Sixteen accessions were successfully sanitized, paving the way to safe yam germplasm exchanges and the implementation of clean seed production programs worldwide