Development of a locus-specific, co-dominant SCAR marker for assisted-selection of the Sw-5 (Tospovirus resistance) gene cluster in a wide range of tomato accessions

The best levels of broad-spectrum Tospovirus resistance reported in tomatoes thus far are conferred by the Sw-5 locus. This locus contains at least five paralogues (denoted Sw-5a through Sw-5e), of which Sw-5b represents the actual resistance gene. Here we evaluated a panel of seven PCR primer pairs matching different sequences within a genomic region spanning the Sw-5a and Sw-5b gene cluster. Primer efficiency evaluation was done employing tomato isolines with and without the Sw-5 locus. One primer pair produced a single and co-dominant polymorphism between susceptible and resistant isolines. Sequence analysis of these amplicons indicated that they were specific for the Sw-5 locus and their differences were due to insertions/deletions. The polymorphic SCAR amplicon encompass a conserved sequence of the promoter region of the functional Sw-5b gene, being located in the position -31 from its open reading frame. This primer pair was also evaluated in field assays and with a collection of accessions known to be either susceptible or resistant to tospoviruses. An almost complete correlation was found between resistance under greenhouse/field conditions and the presence of the marker. Therefore, this primer pair is a very useful tool in marker-assisted selection systems in a large range of tomato accessions

Primer reporte de un marcador molecular asociado a un factor genético de tomate que controla la reacción de tolerancia al virus de la clorosis del tomate (ToCV). [Resumen]

Hasta el momento, el Virus de la Clorosis del Tomate o Tomato chlorosis virus (ToCV) es la única especie de Crinivirus reportada infectando tomate en Sudamérica. Los síntomas típicos son amarillamiento intervenal y senescencia prematura, resultando en la reducción de la capacidad fotosintética. Nuestro trabajo previo identificó accesiones de tomate silvestre y cultivado con altos niveles de tolerancia al desarrollo de síntomas inducidos por ToCV

Una introgresión asociada con el locus Sw-5 del cromosoma 9 de tomate produce un aumento del contenido de ácido ascórbico en fruta madura. [Resumen]

En tomate han sido identificados y mapeados varios loci de herencia cuantitativa (QTL) relacionados al contenido de ácido ascórbico (AA). Algunos colocalizan con diferentes enzimas relacionadas a las rutas metabólicas de AA. Alelos de interés para el mejoramiento han sido identificados en Solanum pennelli, S. habrochaites y S. lycopersicon var cerasiforme

Expresión fenotípica, herencia y localización cromosómica de mtz: locus recesivo que aporta altos niveles de tolerancia a metribuzin en tomate. [Resumen]

El metribuzin es un herbicida ampliamente usado en cultivos de tomate (Solanum lycopersicon) a campo, ya sea para mesa o procesamiento. Los productores generalmente lo utilizan en pre-trasplante o en etapas tempranas del desarrollo del cultivo. Esta información será útil para futuros esfuerzos en identificar candidatos para la identidad genética del locus mtz

Identificación de fuentes genéticas con bajo nivel de síntomas inducidos por Tomato chlorosis virus (ToCV) en germoplasma Solanum sección Lycopersicon. [Resumen]

El virus de la clorosis del tomate o Tomato chlorosis virus (ToCV) pertenece al género Crinivirus, es transmitido por moscas blancas y está asociado a pérdidas de rendimiento y calidad en cultivos de tomate de Sudamérica

Pepper yellow mosaic virus, a new potyvirus in sweet-pepper. Archives of Virology

A potyvirus was found causing yellow mosaic and veinal banding in sweetpepper in Central and Southeast Brazil. The sequence analysis of the 3' terminal region of the viral RNA revealed a coat protein of 278 amino acids, followed by 275 nucleotides in the 3'-untranslated region preceding a polyadenylated tail. The virus shared 77.4% coat protein amino acid identity with Pepper severe mosaic virus, the closest Potyvirus species. The 3'-untranslated region was highly divergent from other potyviruses. Based on these results, the virus found in sweetpepper plants could be considered as a new potyvirus. The name Pepper yellow mosaic virus (PepYMV) is suggeste

Alelo con pérdida de función de un gen tipo TAC-1 (SlTAC1) localizado en el cromosoma 10 de tomate es candidato para el mutante Hoja Erecta (Erl). [Resumen]

La base genética del fenotipo hoja erecta fue investigada en distintas poblaciones, incluida la derivada de Solanum lycopersicum 'LT05' (con hoja erecta y maduración uniforme, genotipo uu) × S. pimpinelifollium 'TO-937' (con fenotipo de hoja salvaje o normal y fruta con hombros verdes, genotipo UU)

Pepper yellow mosaic virus, a new potyvirus in sweet-pepper. Archives of Virology

A potyvirus was found causing yellow mosaic and veinal banding in sweetpepper in Central and Southeast Brazil. The sequence analysis of the 3' terminal region of the viral RNA revealed a coat protein of 278 amino acids, followed by 275 nucleotides in the 3'-untranslated region preceding a polyadenylated tail. The virus shared 77.4% coat protein amino acid identity with Pepper severe mosaic virus, the closest Potyvirus species. The 3'-untranslated region was highly divergent from other potyviruses. Based on these results, the virus found in sweetpepper plants could be considered as a new potyvirus. The name Pepper yellow mosaic virus (PepYMV) is suggeste