Molecular characterization, phylogeny and evolución of Brevipalpus-transmitted viruses in Brazil

Abstract

South America is most likely to be the center of diversity of Brevipalpus-transmitted viruses (BTV). Some of these BTV infect main crops of Brazilian agribusiness such as citrus, coffee, passion fruit, and others several ornamental plants. The genome of some of these viruses, such as Citrus leprosis virus C (CiLV-C) and Coffee ringspot virus (CoRSV) have been described, but the knowledge about several molecular characteristics and processes involved in the evolution of their populations are still scarce. Thus, the objective of this study is the focus on the characterization of the genetic diversity of BTV in Brazil, establish their phylogenetic relationships and reveal the forces involved in the evolution of CiLV-C, the best studied BTV to date. For this purpose, leaves of host plants of BTV with characteristic symptoms will be collected. Following total RNA extraction and NGS, viral genomes will be assembled and compared. To study the evolutionary history of CiLV-C, the causal agent of citrus leprosis, symptomatic citrus samples collected in different decades will be sequenced and compared, comprising 1930s-1940s (citrus samples maintained at the herbarium of Instituto Biologico, Sao Paulo); 2006-2014 (maintained in a -80oC freezer) and from 2016 to 2017, in new sampling. After the sequencing and assembly of the genomes, they will be analyzed using bioinformatic specific packages for population studies. In addition to the clear scientific significance, from a practical point of view this project can contribute to the development of molecular diagnostic tools and the generation of information necessary for the management and control of diseases caused by the studied BTV. (AU)