| Título: | Genome studies of Brazilian isolates of Potato vírus Y (PVY) |
| Autores: | Galvino, Suellen Barbara Ferreira |
| Fecha: |
2014-02-13 2014-02-13 2014 2014 2011-10-31 |
| Publicador: | |
| Fuente: |
Ver documento |
| Tipo: | tese |
| Tema: |
Potato virus (PVY) Batata Potatoes |
| Descripción: |
Potato virus Y (PVY) exists as a complex of strains with multiple types of recombinant genomes. In potato, PVY reduces yield and quality of tubers which makes PVY one of the most important viruses in potato production around the world. Due to a huge information gap about the PVY strain composition and distribution in Brazil, this study aimed to investigate the various strain types in Brazil, their genome structure, possible origins and circulation under Brazilian conditions. Thirty-nine PVY isolates, collected between 1985 and 2009, were typed biologically, serologically, and molecularly. Three of them had their whole genome sequenced and were subjected to a recombination analysis. Furthermore, through tracking the dates of collection of these PVY isolates, an attempt to reconstruct a history of the introduction of recombinant strains into the country was made, considering that these recombinant strains were responsible for dramatic changes in the epidemiology of the virus in Brazilian potato fields. The complete sequencing of PVY-AGA, PVY-MON and PVY-AST showed a novel recombinant genome for PVY-AGA and PVY-MON, whose recombinant parents were identified as PVYNTN and PVY-NE-11, thus proving that the diversity of PVY isolates in Brazil exceeds that found in Europe and North America. The serological, biological and molecular characterization showed that the recombinant strains PVYN-Wi/PVYN:O and PVYNTN are currently dominant over the non-recombinant strains PVYO and PVYN. Three other isolates, PVY-AST, SGS-MO e MU-AGA, presented an unusual serological pattern (MAb2-/1F5 / SASA-N) that had never been reported before for any PVY isolate around the world. The MAF-VOY isolate was PVYO-O5 serotype, which was already described in United States for ordinary strains (PVYO), regardless had being characterized as PVYN-Wi in molecular tests. Taken together, all these results demonstrate the great variability of PVY in Brazil, making difficulty the virus control through resistant potato cultivars. Tese apresentada à Universidade Federal de Lavras, como parte das exigências do Programa de Pós-Graduação em Agronomia/Fitopatologia, área de concentração em Fitopatologia, para obtenção do título de Doutor. |
| Idioma: | en_US |