Enzyme electromorph variation in the lichen family Umbilicariaceae: within-stand polymorphism in umbilicate lichens of eastern Canada

Abstract

This is the first intensive study in which many populations of several lichen species were examined using isoelectric focusing and specific staining to investigate levels of enzyme variability. Enzyme profiles were produced for 48 stands representing the following eastern Canadian species of umbilicate lichens, three of which were mainly apotheciate and three of which were sterile: Lasallia papulosa, Umbilicaria deusta, U. hirsuta, U. mammulata, U. muhlenbergii, and U. vellea. Interthalline variation in electromorph patterns was evident within all 48 stands examined, both sexual and sterile, and levels of variability were generally no higher when apothecia were present. In attempting to characterize any taxon electrophoretically it is thus critical to understand the nature of this variability. Phenomena such as somatic mutations or fusions may contribute to the maintenance of genetic variation in those lichens that have lost the ability to produce meiospores. Key words: lichen, population, variation, enzyme, electromorph, Umbilicaria.