The "Bipartite" Structure of the First Genome of Ampelomyces quisqualis, a Common Hyperparasite and Biocontrol Agent of Powdery Mildews, May Point to Its Evolutionary Origin from Plant Pathogenic Fungi

The dynamics of fungal genome organization and its impact on host adaptation and antifungal resistance

Fungi are a diverse kingdom characterized by remarkable genomic plasticity that facilitates pathogenicity and adaptation to adverse environmental conditions. In this review, we delve into the dynamic organization of fungal genomes and its implications for host adaptation and antifungal resistance. We examine key features and the heterogeneity of genomes across different fungal species, including but not limited to their chromosome content, DNA composition, distribution and arrangement of their content across chromosomes, and other major traits. We further highlight how this variability in genomic traits influences their virulence and adaptation to adverse conditions. Fungal genomes exhibit large variations in size, gene content, and structural features, such as the abundance of transposable elements (TEs), compartmentalization into gene-rich and TE-rich regions, and the presence or absence of dispensable chromosomes. Genomic structural variations are equally diverse in fungi, ranging from whole-chromosome duplications that may enhance tolerance to antifungal compounds, to targeted deletion of effector encoding genes that may promote virulence. Finally, the often-overlooked fungal mitochondrial genomes can also affect virulence and resistance to fungicides. Such and other features of fungal genome organization are reviewed and discussed in the context of host-microbe interactions and antifungal resistance.

IMA GENOME - F20 A draft genome assembly of Agroatheliarolfsii, Ceratobasidiumpapillatum, Pyrenopezizabrassicae, Neopestalotiopsismacadamiae, Sphaerellopsisfilum and genomic resources for Colletotrichumspaethianum and Colletotrichumfructicola

This is a genome announacment there is no abstract

Taxonomic novelty in Pleomonodictydaceae and new reports for Ampelomycesquisqualis (Phaeosphaeriaceae), Melomastiamaolanensis and M.oleae (Pleurotremataceae)

This study introduces a novel genus Robiniigena, with its type R.hyalinospora. The specimen was collected on dead aerial branches of Robiniapseudoacacia in Italy. Based on the examination of morphology and the results of phylogenetic analyses involving nuclear 18S rDNA (SSU), nuclear 28S rDNA (LSU), nuclear rDNA ITS1-5.8S-ITS2 (ITS), translation elongation factor 1-alpha (tef1-α) and RNA polymerase II second largest subunit (rpb2) sequences, Robiniigena is referred to the family Pleomonodictydaceae (Pleosporales). It is characterized by immersed to erumpent, ostiolate ascomata, filiform, septate and cellular pseudoparaphyses, bitunicate, clavate to cylindric-clavate asci and fusiform, hyaline ascospores surrounded by a mucilaginous sheath. This research also establishes the taxonomic placement of the previously unclassified Inflatispora (Pleosporales genus incertae sedis) within the Pleomonodictydaceae. The sexual morph of Ampelomycesquisqualis (Phaeosphaeriaceae) is described for the first time and it is characterized by immersed, perithecial ascomata, a peridium comprising two layers, branched, septate and filiform pseudoparaphyses, short-pedicellate, bitunicate asci with an ocular chamber and sub-hyaline, fusiform, septate ascospores. This species, previously known only in its asexual morph, has been found as a saprobe on Sonchus sp. in Italy. Our identification of the sexual morph was based on LSU rDNA and ITS rDNA sequence data. Melomastiamaolanensis (Pleurotremataceae) is reported for the first time in Thailand, collected from Chromolaenaodorata, while M.oleae is documented as a new record from Durantaerecta in Thailand.

Genome-wide survey of the bipartite structure and pathogenesis-related genes of Neostagonosporella sichuanensis, a causal agent of Fishscale bamboo rhombic-spot disease

Bamboo resources have garnered significant global attention due to their excellent capacity for regeneration and high yield. Rhombic-spot disease, a substantial threat to fishscale bamboo (Phyllostachys heteroclada), is primarily caused by Neostagonosporella sichuanensis. This study first reported the genome assemblies and characteristics of two N. sichuanensis isolates using PacBio and Illumina sequencing platforms. The genomes of N. sichuanensis strain SICAUCC 16-0001 and strain SICAUCC 23-0140, with sizes of 48.0 Mb and 48.4 Mb, respectively, revealed 10,289 and 10,313 protein-coding genes. Additionally, they contained 34.99 and 34.46% repetitive sequences within AT-rich regions, with notable repeat-induced point mutation activity. Comparative genome analysis identified 1,049 contracted and 45 expanded gene families in the genome of N. sichuanensis, including several related to pathogenicity. Several gene families involved in mycotoxin metabolism, secondary metabolism, sterol biosynthesis and transport, and cell wall degradation were contracted. Compared to most analyzed necrotrophic, hemibiotrophic, and phaeosphaeriacous pathogens, the genomes of two N. sichuanensis isolates exhibited fewer secondary metabolite enzymes, carbohydrate-active enzymes, plant cell wall degrading enzymes, secreted proteins, and effectors. Comparative genomics analysis suggested that N. sichuanensis shares more similar characteristics with hemibiotrophic pathogens. Based on single carbon source tests, N. sichuanensis strains demonstrated a higher potential for xylan decomposition than pectin and cellulose. The proportion of cell wall-degrading enzyme effectors occupied a high proportion of the total effectors of the N. sichuanensis genomes. These findings provide valuable insights into uncovering the pathogenesis of N. sichuanensis toward the efficient management of rhombic-spot disease of fishscale bamboo.

Hyperparasitic Fungi on Black Mildews (Meliolales, Ascomycota): Hidden Fungal Diversity in the Tropics

Hyperparasitism on plant-parasitic fungi is a widespread but rarely studied phenomenon. Here, for the first time, we compile in a checklist information provided by peer-reviewed literature for fungi growing on colonies of black mildews (Meliolales, Ascomycota), a species-rich group of tropical and subtropical plant-parasitic microfungi. The checklist contains information on 189 species of contact-biotrophic microfungi in 82 genera. They belong to seven morphological groups: dematiaceous hyphomycetes, moniliaceous hyphomycetes, pycnidioid, perithecioid, catathecioid, and apothecioid fungi. By the fact that species accumulation curves do not reach saturation for any tropical country, it is evident that the knowledge of the diversity of hyperparasitic fungi on Meliolales is incomplete. A network analysis of records of hyperparasitic fungi, their host fungi and host plants shows that genera of hyperparasitic fungi are generalists concerning genera of Meliolales. However, most species of hyperparasitic fungi are restricted to meliolalean hosts. In addition to hyperparasitic fungi, diverse further microorganisms use meliolalean colonies as ecological niche. Systematic positions of most species are unknown because DNA sequence data are lacking for species of fungi hyperparasitic on Meliolales. We discuss the specific challenges of obtaining DNA sequence data from hyperparasitic fungi. In order to better understand the diversity, evolution and biology of hyperparasitic fungi, it is necessary to increase sampling efforts and to undertake further morphological, molecular, and ecological studies.