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Isolation, Behavioral Identification, and Pathogenicity Assessment of Entomopathogenic Fungi from a Forest Wood Borer
Published on: September 29, 2023
An expanded multilocus phylogeny does not resolve morphological species within the small-spored Altemrnaria species
M Andrew1, T L Peever, B M Pryor
1Department of Plant Pathology, Washington State University, Pullman, Washington 99164-6430, USA.
Mycologia
|March 11, 2009
Summary
Identifying small-spored Alternaria species is difficult. New genomic markers reveal distinct evolutionary lineages, but host and geography are not useful for classification. Morphology is only partially reliable for grouping these fungi.
Area of Science:
- Mycology
- Fungal Systematics
- Molecular Phylogenetics
Background:
- Small-spored Alternaria species present significant taxonomic challenges due to limited distinguishing morphological and molecular characters.
- Traditional protein-coding genes are invariant, necessitating the exploration of noncoding genomic regions for phylogenetic analysis.
Purpose of the Study:
- To develop and assess novel molecular markers for resolving evolutionary relationships within small-spored Alternaria species.
- To evaluate the utility of host association, geographic origin, and morphology as taxonomic characters in conjunction with phylogenetic data.
Main Methods:
- Screened nineteen sequence-characterized amplified regions (SCAR) for phylogenetic utility in small-spored Alternaria.
- Conducted phylogenetic analyses on 150 isolates using an endopolygalacturonase gene and two validated anonymous loci.
- Assessed correlations between phylogenetic lineages, morphology, geography, and host plant associations.
Main Results:
- Five of nineteen SCAR loci demonstrated consistent amplification and phylogenetic signal.
- No significant associations were found between phylogenetic lineage and host or geographic origin.
- Morphological groupings with *A. alternata* and *A. tenuissima* showed poor congruence with phylogenetic data, while isolates matching *A. arborescens* formed discrete clades.
Conclusions:
- Novel anonymous genomic loci provide valuable phylogenetic resolution for small-spored Alternaria.
- Host and geographic data are not reliable for cladistic classification of these fungi.
- While distinct clades were identified, their status as species or lineages within the *A. alternata* group requires further investigation.
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