Degree Type


Date of Award


Degree Name

Doctor of Philosophy




The Polyporaceae are a large group of wood-rotting fungi belonging to the basidiomycetes. They are generally recognized by their leathery or corky sporocarps which usually have a poroid hymenophore. Early classification of this family consisted of about a dozen genera. More recent treatments have recognized over 100 polypore genera. Because many of these new taxa are based on a subjective evaluation, this study has explored a more objective method for establishing generic limits in the Polyporaceae;Twenty species distributed in nine genera were selected primarily on the basis of availability for electrophoresis. These 20 taxa were assayed for eight enzymes by means of horizontal starch gel electrophoresis. A total of 108 bands were identified, and these data were analyzed by numerical analysis. Morphological data based on 24 characters were also analyzed by similar methods. The results are presented as dendrographs and ordinations. Cluster analyses of morphological and electrophoretic data consisted of similar groups of species. Ordination of both types of data produced only a few discrete taxonomic groupings, but gradations of certain OTUs still reflect some taxonomic integrity;The special significance of this study is that there is taxonomic congruence between the morphological and electrophoretic data. That is, one classification based on one set of characters reflect a classification obtained by a separate class of characters. The misplaced OTUs and lack of discrete clusters for certain species may be due to the small sample sizes employed in this study. Other sources of distortion may be caused by different algorithms and ordinations techniques used in the analyses of different types of data;A checklist of the polypores of Iowa is also presented in this study. This inventory is based on an examination of specimens from the SUI Herbarium and recent field collections. An updated nomenclature for 151 species distributed in 59 genera is included in the checklist.



Digital Repository @ Iowa State University,

Copyright Owner

Robert John Pinette



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70 pages

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Botany Commons