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Genetic Diversity of Tomato (Solanum lycopersicum L.) Begomovirus in Togo  [PDF]
Assion Sétu Mivedor, Justin Simon Pita, Kossikouma Djodji Adjata, Jér?me Duclercq, Yawovi Mawuena Dieudonné Gumedzoe
Agricultural Sciences (AS) , 2017, DOI: 10.4236/as.2017.812100
Abstract:
Geminiviruses, in particular the members of the genus Begomovirus , are considered to be a major phytosanitary problem for tomato crops production in the world. They are responsible for yield losses of up to 20% to 100%. Regrettably, Togo is not spared from this situation. This work aims to show the genetic diversity of the begomoviruses affecting tomato crops production in Togo and their relationship with other begomoviruses. To achieve these objectives, 307 samples of tomato leaves and wild plant species with typical virus symptoms were collected in the Maritime, Plateaus, Central, Kara and Savannah regions and submitted to PCR analysis. The results revealed the presence of begomovirus in 25.40% of the analyzed samples. The PCR products obtained were submitted to direct sequencing. Phylogenetic analysis of sequences of DNA-A different regions of begomovirus identified in this work with that of other begomoviruses showed a nucleotide identity of 96% respectively for Tomato leaf curl Togo virus-Fontem, Tomato Leaf Curl Togo Virus , Ageratum leaf curl Cameroon Alphasatellite; 98% respectively to Tomato leaf curl Nigeria virus , Ageratum leaf curl Cameroon virus , Tomato leaf curl Cameroon virus-Fontem, Ageratum leaf curl Cameroon virus and 99% respectively to Tomato leaf curl Kumasi virus , Pepper yellow vein Mali virus Bazegahot and Pepper yellow vein Mali virus-Ouaga. These results suggest a high degree of genetic diversity of tomato begomoviruses identified in Togo.
Identifica??o dos genes Ty-2 e Ty-3 de resistência a begomovírusem genótipos de tomateiro
Aguilera, Jorge González;Hurtado, Francisco Due?as;Xavier, Cesar Augusto Diniz;Laurindo, Bruno Soares;Nick, Carlos;Gil, Marta álvarez;Silva, Derly José Henriques da;Zerbini, Francisco Murilo;
Pesquisa Agropecuária Brasileira , 2011, DOI: 10.1590/S0100-204X2011000700014
Abstract: the objective of this work was to identify the presence of the genes begomovirus resistence ty-2 and ty-3 in tomato accessions of the banco de germoplasma de hortali?as of the universidade federal de vi?osa. the oligonucleotides to302 f/r and fluw25 f/r were used in pcr analysis to verify the presence of markers associated to the genes ty-2 and ty-3, respectively. the ty-2 gene was observed in heterozygosis in the accession bgh-6881 (solanum peruvianum), and the ty-3 gene in homozygosis in the accessions bgh-6878, bgh-6897 (s. lycopersicum), and in heterozygosis in acession bgh-6881. the identification of resistance genes, using pcr analysis, represents an advance for tomato breeding programs in brazil.
Identificación de los genes Ty-2 y Ty-3 de resistencia a Begomovirus y su grado de homocigosis en nuevas accesiones de tomate
Due?as,F; álvarez,Marta; Moya,C; Martínez,Yamila; Peteira,Belkis; Arias,Yailen;
Cultivos Tropicales , 2009,
Abstract: the tomato yellow leaf curl virus (tylcv) is one of the most dangerous begomovirus affecting tomato productions in cuba. at present, several genes related to resistance have been described. ty-1, ty-2 and ty-3 are the most widely used genes in plant breeding programs. in cuba, there is only one ty-1 gene-carrier called vyta. this work identified the presence of the band related to ty-2 gene resistant pattern in two characterized materials. for ty-3 gene, all genotypes showed the susceptible pattern.
Distribución y diversidad genética de Begomovirus que infectan tomate (Solanum lycopersicum L) en Colombia  [cached]
Vaca-Vaca Juan Carlos,Betancur-Pérez Jhon Fredy,López-López Karina
Revista Colombiana de Biotecnología , 2012,
Abstract: Título en ingles: Distribution and genetic diversity of tomato –infecting Begomovirus in Colombia Resumen: Las enfermedades causadas por los begomovirus, (Familia Geminiviridae) constituyen una serie limitante para la producción del tomate en Colombia. Sin embargo, la caracterización de estos virus no ha sido realizada al momento. Aquí presentamos los resultados de un muestreo a nivel nacional que buscaba conocer la distribución y diversidad genética de los geminivirus que están afectando el cultivo de tomate en Colombia. Los virus fueron detectados mediante PCR, empleando primer universales específicos para el género Begomovirus. Los fragmentos amplificados por PCR fueron sometidos a un análisis tipo RFLP cuyos resultados evidenciaron presencia de infecciones mixtas e individuales de geminivirus en la mayoría de las muestras recolectadas en campo. Los fragmentos amplificados por PCR fueron clonados y secuenciados. El análisis de secuencia y filogenético mostró que los aislados begomovirales colombianos eran gemininivirus bipartitas típicos del Hemisferio Occidental y que algunos eran variantes de PYMV y otros de ToTEV. Mediante el análisis de los elementos cis-regulatorios (iterones) presentes en el promotor del gen de la proteína asociada a replicación (Rep) de los begomovirus aislados es posible postular eventos de pseudorecombinación que podrían suceder entre ellos durante la ocurrencia de infecciones mixtas en tomate. Palabras claves: Geminivirus; Solanum licopersicum; PCR-RFLP; infecciones mixtas. Abstract: Diseased caused by begomoviruses (Family Geminiviridae) constitute a serious constraint to tomato production in Colombia. However characterization of these new viruses had not been carried out so far. Here we report a large scale survey on the distribution and genetic diversity of tomato infecting geminiviruses which are affecting mayor growing area of this crop in the country. Viruses were detected by PCR using universal primers for members of genus Begomovirus. The RFLP analysis of PCR-amplified fragments showed individual and mixed infections of several geminiviruses in many of the samples. PCR-amplified fragments were cloned and sequenced. Based on sequence comparations and phylogenetic analysis, the Colombian geminivirus isolates were new world bipartite geminiviruses showing close relationship with PYMV and ToVEV. By means of bioinformatic analysis of cis-acting elements (iterons) involved in DNA replication of rep gene of Colombian geminivirus isolates was possible to postulate possible pseudorecombinación events that could occur betwee
Distribución y diversidad genética de Begomovirus que infectan tomate (Solanum lycopersicum L) en Colombia
Vaca-Vaca,Juan Carlos; Betancur-Pérez,Jhon Fredy; López-López,Karina;
Revista Colombiana de Biotecnología , 2012,
Abstract: diseased caused by begomoviruses (family geminiviridae) constitute a serious constraint to tomato production in colombia. however characterization of these new viruses had not been carried out so far. here we report a large scale survey on the distribution and genetic diversity of tomato infecting geminiviruses which are affecting mayor growing area of this crop in the country. viruses were detected by pcr using universal primers for members of genus begomovirus. the rflp analysis of pcr-amplified fragments showed individual and mixed infections of several geminiviruses in many of the samples. pcr-amplified fragments were cloned and sequenced. based on sequence comparations and phylogenetic analysis, the colombian geminivirus isolates were new world bipartite geminiviruses showing close relationship with pymv and tovev. by means of bioinformatic analysis of cis-acting elements (iterons) involved in dna replication of rep gene of colombian geminivirus isolates was possible to postulate possible pseudorecombinación events that could occur between them but also confirm the occurrence of mixed infections.
Reaction of tomato hybrids carrying the Ty-1 locus to Brazilian bipartite Begomovirus species
Boiteux, Leonardo Silva;Oliveira, Valter Rodrigues;Silva, Cézar Honório;Makishima, Nozomu;Inoue-Nagata, Alice K;Fonseca, Maria Esther de Noronha;Giordano, Leonardo de Britto;
Horticultura Brasileira , 2007, DOI: 10.1590/S0102-05362007000100005
Abstract: the number of tomato-infecting begomoviruses has increased in brazil after the introduction of the polyphagous vector bemisia tabaci biotype b. the ty-1 locus, introgressed from lycopersicon chilense, controls tolerance to species of the monopartite tomato yellow leaf curl virus (tylcv) complex in europe and the middle east. however, little information is available about the ty-1 effectiveness against species of the bipartite begomovirus complex occurring in brazil. heterozygous (ty-1/ty-1) and homozygous (ty-1/ty-1) hybrids were evaluated for reaction to begomovirus isolates under open field conditions in two growing areas in central brazil. test plants were evaluated under natural inoculation with high vector pressure. evaluation was done using a disease assessment scale (das) varying from 1= no symptoms to 4= severe symptoms. systemic infection was evaluated via polymerase chain reaction (pcr) using 'universal' begomovirus primers. in the trial #1, the hybrids (ty-1/ty-1) and (ty-1/ty-1) had 35% and 95% of plants with symptoms and 75% and 100% of plants with positive pcr, respectively. in the trial #2, only 20% of the ty-1/ty-1 hybrid plants were symptom-free with both hybrids displaying 100% of plants with positive pcr. this reaction of the ty-1 hybrid to bipartite begomovirus species was similar to that reported in europe and the middle east to the tylcv complex with a large number of plants being neither virus-free nor symptom-free. on the other hand, symptom expression of the ty-1 hybrid was significantly milder than ty-1/ty-1 hybrids in both trials (das = 1.35 vs. 2.70 for the trial #1 and das = 2.05 vs. 3.95 for the trial #2). nucleotide sequencing indicated the presence of isolates genetically related to tomato rugose mosaic virus (tormv) in the trial #1 and a mixed infection of tormv and tomato yellow vein streak virus in the trial #2. therefore, the ty-1 locus seems to control a "tolerance" response to distinct begomovirus species. resistance gene cluste
Marcador microssatélite associado ao alelo Ty-1 de resistência a Begomovirus em tomateiro
Nogueira, Danilo Gustavo;Maluf, Wilson Roberto;Nogueira, Douglas Willian;Maciel, Gabriel Mascarenhas;Paiva, Luciano Vilela;Figueira, Ant?nia dos Reis;
Pesquisa Agropecuária Brasileira , 2011, DOI: 10.1590/S0100-204X2011000400011
Abstract: the objective of this work was to associate a microsatellite marker with the ty-1 allele that controls resistance to begomovirus in tomatoes, and to assess the eficiency of this association in the selection of virus-resistant lines. microsatellite markers ssr-47 and ssr-48 were tested in near isogenic tomato lines (la-3473, la-3474, la-3475) with contrasting genotypes for the ty-1 allele. the marker ssr-47 detected polymorphism in the lines, and was the only one used in the subsequent research phases. an association between the ssr-47 marker and the ty-1 locus was detected, and its efficiency for selection of begomovirus-resistant genotypes in tomato was assessed. to confirm the selection efficiency, plants with contrasting banding patterns for the ssr-47 marker were tested for their reaction to begomovirus. all plants with a single 191-bp band were resistant to begomovirus, through inoculation test by grafting. plants with a single 180-bp band were susceptible, and plants with both 191bp and 180 bp bands were resistant. the maximum distance between ty-1 and the ssr-47 marker was 2.7 cm. this marker was efficient to identify genotypes bearing the ty-1 allele. plant responses to infection by begomovirus inoculated through grafting were consistent with reactions predicted with the use of the ssr-47 marker.
SolDB: A Database of Solanum lycopersicum and Solanum tuberosum Primers  [PDF]
Hassan Tariq,Shahid Nadeem,Muhammad Sohail Raza,Sobia Idrees
International Journal Bioautomation , 2010,
Abstract: SolDB is the Database of Solanaceae Family. It is an interactive, free online specialized database for Solanaceae family. Currently, it spans complete nucleotide sequences of expressed genes of Solanum lycopersicum and Solanum tuberosum along with their annotation. We have designed PCR oligonucleotide primer sequences for each gene, with their features and conditions given. This feature alone greatly facilitates researchers in PCR amplification of genes sequences, especially in cloning experiments. We also provided chloroplast genome section which gives access to fully sequenced plastid genomes and their annotations. Flexible database design, easy expandability, and easy retrieval of information are the main features of SolDB. The Database is publicly available at www.soldb.pakbiz.org.
CARACTERIZACIóN AGROMORFOLóGICA Y EVALUACIóN DE LA RESISTENCIA AL TYLCV EN NUEVOS GENOTIPOS DE TOMATE (SOLANUM LYCOPERSICUM L.) COMO APOYO AL PROGRAMA DE MEJORAMIENTO GENéTICO DE LA HORTALIZA PARA LA ENFERMEDAD
Due?as,F; álvarez,Marta; Moya,C; Martínez,Yamila; Peteira,Belkis; Arias,Yailén; Diez,María J; Hanson,P; Shagarodski,T;
Cultivos Tropicales , 2008,
Abstract: one of the major viral pathogens of tomato (solanum lycopersicum l.) crop in cuba and many other countries is the tomato yellow leaf curl virus (tylcv), a begomovirus from geminiviridae family, which are transmitted by the whitefly bemisia tabaci (genn.). at present, plant breeding for disease resistance or tolerance constitutes one of the most promising ways to reduce damages caused by this virus, since most existing tomato seedlings are susceptible to it. this study evaluated the agromorphological characteristics and resistance to tylcv of eight tomato genotypes introduced in our country. from the agromorphologic viewpoint, a phenotypical variability was detected in all materials evaluated. except the susceptible control, every accession was asymptomatic to the virus; however, viral concentrations were recorded just in some sampled plants of these accessions
Herbivory induces differential gene expression in Solanum lycopersicum cultivars  [PDF]
Thimmappa Raghava,Puja Ravikumar,Rajendra Hedge,Anil Kush
Communications in Plant Sciences , 2013,
Abstract: Solanum lycopersicum cultivars display differential response to biotic stress. Three agronomically important tomato cultivars viz. All Rounder, Lakshmi and Shaktiman were subjected to equal amount of Spodoptera litura Fab. damage at anthesis stage. Expression levels of four genes CORONATINE INSENSITIVE-1 (COI-1), Leucylaminopeptidases (LAP), Peptidyl propyl isomerase (PPI) and DNA binding protein (DBP) involved in Jasmonate signaling pathway, oxidative stress response and defense responses were determined by Semi-Quantitative RT-PCR. A significantly enhanced expression of COI-1 transcript (p=0.05) was observed in induced samples of all three cultivars as compared to their uninduced samples. In Cultivar Lakshmi, the expression of LAP transcript increased 2 fold in response to herbivory. PPI & DBP transcript levels were compromised and varied widely across cultivars. Within species variation was evident in case of COI-1 & LAP transcripts expression. Elucidating the differential expression levels of key targets provides us clues for developing insect tolerant cultivars.
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