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The genus Rugosporella is proposed to accommodate Peziza atrovinosa in the modern classification scheme of the Pezizaceae. We used DNA sequences of ITS, LSU and RPB2 to resolve the phylogenetic placement of this taxon. The species occupies a distinct position within a large and diverse clade of hypogeous and epigeous taxa, all of which are either known to be or presumed to be ectomycorrhizal. Although no DNA sequences of this species have been identified from ectomycorrhizal roots, we provide isotopic data supporting its ectomycorrhizal lifestyle. Peziza atrovinosa is distinctive in its moderately large vinaceous brown apothecia with thick flesh and the relatively small ascospores that are ornamented with a high reticulum and that become yellow-brown at maturity. This species is found across eastern North America.
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Effective Field Collection of Pezizales Ascospores for Procuring Diverse Fungal Isolates
Pezizales are a diverse and economically important order of fungi. They are common in the environment, having epigeous form, such as morels and hypogeous, forms called truffles. The mature ascospores of most epigeous Pezizales are forcibly discharged through an opening at the ascus apex created with the lifting of the operculum, a lid-like structure specific to Pezizales. The axenic cultures of Pezizales fungi isolated from single ascospores are important for understanding the life cycle, development, ecology, and evolution of these fungi. However, obtaining single-spore isolates can be challenging, particularly for collections obtained in locations where sterile work environments are not available. In this paper, we introduce an accessible method for harvesting ascospores from fresh ascomata in the field and laboratory for obtaining single-spore isolates. Ascospores are harvested on the inside cover of Petri plate lids in the field, air dried, and stored. At a later date, single-spore isolates are axenically cultured through serial dilution and plating on antibiotic media. With this approach, we were able to harvest ascospores and obtain single-spore isolates from 12 saprotrophic and 2 ectomycorrhizal species belonging to six Pezizales families: Discinaceae, Morchellaceae, Pezizaceae, Pyronemataceae, Sarcosomataceae, and Sarcoscyphaceae. This method worked well for saprotrophic taxa (12 out of 19 species, 63%) and was even effective for a few ectomycorrhizal taxa (2 out of 13 species, 15%). This process was used to study the initial stages of spore germination and colony development in species across several Pezizales families. We found germination often commenced with the swelling of the spore, followed by the emergence of 1–8 germ tubes. This method is sufficiently straightforward that, provided with sterile Petri dishes, citizen scientists from distant locations could use this approach to capture spores and subsequently mail them with voucher specimens to a research laboratory for further study. The generated single-spore Pezizales isolates obtained through this method were used to generate high-quality genomic data. Isolates generated in this fashion can be used in manipulative experiments to better understand the biology, evolution, and ecogenomics of Pezizales.
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- Award ID(s):
- 1946445
- PAR ID:
- 10585098
- Publisher / Repository:
- Diversity
- Date Published:
- Journal Name:
- Diversity
- Volume:
- 16
- Issue:
- 3
- ISSN:
- 2291-0557
- Page Range / eLocation ID:
- 165
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/d16030165
