Biology subjects

Ferro, C. G.

Publications and source records attributed to Ferro, C. G..

2 recordsLinked to original sources

bioRxiv2022

The Brazilian population of Fusarium oxysporum f. sp. cubense is not structured by VCG or by geographic origin

Fusarium wilt, caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense (Foc), is considered one of the most destructive diseases of bananas. Paradoxically, knowledge of the genetics of the pathogen population in the Americas is very limited. In this study, a collection of 178 monosporic isolates from several banana producing regions, located in different climatic zones along a South to North transect in Brazil, was formed to assess the genetic structure of the population of Foc. The isolates underwent pathogenicity tests, PCR diagnosis for the detection of Tropical race 4 and screening to SIX homologs. The VCG of 119 isolates was determined by pairing against 17 testers. A group of 158 isolates was selected for microsatellite genotyping. There was moderate diversity of Foc in Brazil. Eight VCGs were identified: 0120, 0122, 0124, 0125, 0128, 01215, 01220, and 01222, of which 78% of isolates belong to a single VCG, while 22% of isolates belong to complexes of VCGs. The distribution of VCGs is uneven and independent of the banana genotype. VCGs were correlated with homologs of the SIX genes and varied according to geographic regions. Four SSR loci were polymorphic and on average 7.5 alleles were detected per locus. Thirty-five multilocus genotypes (MLGs) were identified. There was no association between VCG and MLGs and no genetic structure of the population of Foc in Brazil was detected.

microbiology↗

bioRxiv2020

Evolutionary dynamics of bipartite begomoviruses revealed by complete genome analysis

Several key evolutionary events marked the evolution of geminiviruses, culminating with the emergence of bipartite genomes represented by viruses classified in the genus Begomovirus. This genus represents the most abundant group of multipartite viruses, contributing significantly to the observed abundance of multipartite species in the virosphere. Although aspects related to virus-host interactions and evolutionary dynamics have been extensively studied, the bipartite nature of these viruses has been little explored in evolutionary studies. We performed a parallel evolutionary analysis of the DNA-A and DNA-B components of New World begomoviruses. A total of 239 full-length DNA-B sequences obtained in this study, combined with 292 DNA-A and 76 DNA-B sequences retrieved from GenBank, were analyzed. The results indicate that the DNA-A and DNA-B respond differentially to evolutionary processes, with the DNA-B being more permissive to variation and more prone to recombination than the DNA-A. Although a clear geographic segregation was observed for both components, differences in the genetic structure between DNA-A and DNA-B were also observed, with cognate components belonging to distinct genetic clusters. DNA-B coding regions evolve under the same selection pressures than DNA-A coding regions. Together, our results indicate an interplay between reassortment and recombination acting at different levels across distinct subpopulations and components.

microbiology↗