Hébrard Eugénie auteur aut IRD Fargette Denis auteur aut IRD Konaté G. auteur aut IRD text bookSection eng text/pdf born digital access Rice yellow mottle virus (RYMV) causes the most important rice disease in Africa. RYMV belongs to the genus Sobemovirus. RYMV has icosahedral particles of 25 nm in diameter. The virions contain a single coat protein (CP) of 29 kDa, a genomic RNA, and one subgenomic RNA molecule. The genomic RNA is one single-stranded messenger-sense molecule, 4450 nt in size. The 5′ terminus of the RNAs has a genome-linked protein (VPg), and lacks a poly(A) tail. RYMV often encapsidates, in addition to its genomic RNA, a viroid-like satellite RNA. The RYMV genome is organized in four overlapping open reading frames (ORFs). The ORF1 encodes a protein P1 required for cell-to-cell movement of the virus. P1 is a suppressor of posttranslational gene silencing. The ORF2a contains sequence motifs for the proteinase and the VPg. The ORF2b encodes the RNA-dependent RNA polymerase. The ORF4 is translated from the subgenomic RNA and encodes the CP. The natural host range of RYMV is restricted to a few members of the Poaceae family. Transmission is due to chrysomelidae vectors and to contact during cultural practices. The more efficient resistance called high resistance encodes the translation initiation factor eIF(iso)4G. This resistance is overcome by a point mutation in the VPg. The evolution of RYMV has been inferred from its genetic diversity. specialized MALADIE DES PLANTES RIZ VIRUS RESISTANCE 076MALPLA02 Mahy B.W.J. ed. edt IRD Van Regenmortel M.H.V. ed. edt IRD 485-490 Oxford Elsevier 2008 https://www.documentation.ird.fr/hor/fdi:010069672 978-0-12-374410-4 [F B010069672] https://www.documentation.ird.fr/hor/fdi:010069672 https://www.documentation.ird.fr/intranet/publi/depot/2017-05-22/010069672.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2017-05-19 2017-11-02 fdi:010069672 fre