89 research outputs found
Analysis of genotypic diversity provides a first glimpse on the patterns of spread of the wood decay fungus Perenniporia fraxinea in an urban park in northern Italy
Detection, host preference and role on tree stability of wood decay fungi in urban environment
Comparative genomics between the invasive forest pathogen Heterobasidion irregulare and the native sibling species H. annosum provide a glimpse into their divergent adaptive evolution
Comparative Genomics of Sibling Fungal Pathogenic Taxa Identifies Adaptive Evolution without Divergence in Pathogenicity Genes or Genomic Structure
It has been estimated that the sister plant pathogenic fungal species Heterobasidion irregulare and Heterobasidion annosum may have been allopatrically isolated for 34–41 Myr. They are now sympatric due to the introduction of the first species from North America into Italy, where they freely hybridize. We used a comparative genomic approach to 1) confirm that the two species are distinct at the genomic level; 2) determine which gene groups have diverged the most and the least between species; 3) show that their overall genomic structures are similar, as predicted by the viability of hybrids, and identify genomic regions that instead are incongruent; and 4) test the previously formulated hypothesis that genes involved in pathogenicity may be less divergent between the two species than genes involved in saprobic decay and sporulation. Results based on the sequencing of three genomes per species identified a high level of interspecific similarity, but clearly confirmed the status of the two as distinct taxa. Genes involved in pathogenicity were more conserved between species than genes involved in saprobic growth and sporulation, corroborating at the genomic level that invasiveness may be determined by the two latter traits, as documented by field and inoculation studies. Additionally, the majority of genes under positive selection and the majority of genes bearing interspecific structural variations were involved either in transcriptional or in mitochondrial functions. This study provides genomic-level evidence that invasiveness of pathogenic microbes can be attained without the high levels of pathogenicity presumed to exist for pathogens challenging naïve hosts
A molecular diagnostic assay for the detection and identification of wood decay fungi of conifers
Comparing visual inspection of trees and molecular analysis of internal wood tissues for the diagnosis of wood decay fungi
Mitonuclear interactions may contribute to fitness of fungal hybrids
Abstract Hybridization between species is being recognized as a major force in the rapid adaptive evolution of fungal plant pathogens. The first stages of interspecific hybridization necessarily involve nuclear-mitochondrial chimeras. In their 2001 publication, Olson and Stenlid reported that mitochondria control the virulence of first generation hybrids between the North American fungal pathogen Heterobasidion irregulare and its congeneric H. occidentale. By assessing saprobic ability and gene expression of H. irregulare × H. annosum sensu stricto hybrids and of their parental genotypes, we demonstrate that mitochondria also influence saprobic growth of hybrids. Moreover, gene expression data suggest that fungal fitness is modulated by an intimate interplay between nuclear genes and mitochondrial type, and is dependent on the specific mitonuclear combination
Modelling the effects of climate on the incidence of the nut rot of chestnuts caused by Gnomoniopsis castanea
Relations between the climate and the incidence of the nut rot of chestnuts caused by Gnomoniopsis castanea
Development of practical tools for the monitoring and the control of the invasive plant pathogen Heterobasidion irregulare in central Italy.
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