An evolutionary view of the Fusarium genome

Abstract

Fusarium is an Ascomycota with several relevant pathogenic species of plants and animals. Some phytopathogenic species have received special attention due to their negative economic impact on the agricultural industry around the world. Traditionally, identification and taxonomic analysis of Fusarium have relied on morphological and phenotypic features, including the hosts of the fungus, leading to taxonomic conflicts that have been solved using molecular systematic technologies. In this work, we applied a phylogenomic approach that allowed us to resolve the evolutionary history of the species complexes of the genus and present evidence that supports the F. ventricosum species complex as the most basal lineage of the genus. Additionally, we present evidence that proposes modifications to the previous hypothesis of the evolutionary history of the F. staphyleae, F. newnesense, F. nisikadoi, F. oxysporum, and F. fujikuroi species complexes. Evolutionary analysis showed that the genome GC content have a tendency to be lower in more modern lineages, below 49.3%, while genome size gain and losses are present during the evolution of the genus. Interestingly core genome duplication events have a positive correlation with the genome size. Evolutionary and genome conservation analysis supports the F3 hypothesis of Fusarium as a more compact and conserved group in terms of genome conservation. By contrast the most basal clades, outside the F3 hypothesis only share 8.8% of its genomic sequences with the F3 clade.