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Isolation of Culturable Yeasts and Molds from Soils to Investigate Fungal Population Structure
Published on: May 27, 2022
Sexual structures in Aspergillus: morphology, importance and genomics.
1Department of Plant Pathology, The Pennsylvania State University, University Park, PA 16802, USA. dgeiser@psu.edu
Medical Mycology
|July 9, 2008
Summary
The study reveals that many Aspergillus species capable of sexual reproduction are homothallic, meaning they can self-fertilize. Evidence suggests sex occurs even in species lacking a known sexual stage, challenging assumptions about fungal life cycles.
Area of Science:
- Mycology
- Fungal Genetics
- Evolutionary Biology
Background:
- The genus Aspergillus includes hundreds of species, many with asexual spores (conidia).
- About one-third of Aspergillus species also exhibit a sexual stage (teleomorph), with most being homothallic.
- Sexual stages of Aspergillus are classified into ten genera within the Eurotiales order, indicating significant diversity.
Purpose of the Study:
- To investigate the reproductive modes of Aspergillus species.
- To explore the phylogenetic and biological diversity of sexual stages in Aspergillus.
- To determine if sexual reproduction occurs in Aspergillus species without a known sexual stage.
Main Methods:
- Analysis of existing literature on Aspergillus reproductive biology.
- Phylogenetic and genetic studies to infer the presence of sexual reproduction.
- Population genetic and genomic analyses.
Main Results:
- Homothallic sexual reproduction is common in Aspergillus, allowing for self-fertilization.
- Sexual stages are diverse, spanning multiple genera within the Eurotiales.
- Population genetic and genomic data indicate that sexual reproduction (sex) occurs in Aspergillus species even when a sexual stage is not morphologically observed.
Conclusions:
- The presence of a known sexual stage does not preclude asexual reproduction, and vice versa.
- Sexual reproduction in Aspergillus may be more widespread than previously recognized.
- Assumptions about a species' life history (clonal vs. recombinant) cannot be solely based on observed reproductive modes.
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