Joseph Spatafora
|
Professor, Botany and Plant Pathology |
|||||||||||||||
 |
|
||||||||||||||
Education
Ph.D. 1986, Louisiana Tech UniversityResearch
Progress in fungal systematics was greatly impeded by the paucity of morphological characters coupled with the phenotypic plasticity of fungi. The advent of molecular systematics alleviated many of these problems by providing large data sets that are independent of morphology and can be reproducibly analyzed. The focus of our laboratory's research is molecular phylogenetics of fungi with an emphasis on the evolutionary biology of ascomycete symbioses and the phylogenetic integration of ecologically disparate groups of fungi.Ascomycetes form a myriad of symbioses with all major groups of life on earth. These symbioses may range from parasitic to mutualistic. Two classic ascomycete symbioses addressed by researchers in our lab are those with algae (lichens) and arthropods. Lichens are the quintessential example of symbiosis in most general biology and botany textbooks, yet little is known about the evolutionary origins of lichenized ascomycetes. If accurate inferences regarding the evolution of ascomycetes are to be made, lich enized and nonlichenized forms must be considered simultaneously. Molecular phylogenetics provides a means to integrate these two forms in a common data set.
Ascomycete-arthropod symbioses are diverse and evolutionary dynamic associations. Many species independently evolved arthropod-dispersed ascospores. They possess strikingly similar morphologies and life histories that are the process of strong selection pressures and convergent evolution. The Ophiostomatales, which comprises several plant pathogens including the causal agent of Dutch Elm disease, is a one such group that is the focus of research in our lab. Another group containing entomogenous as well as other host-specific fungi is the Clavicipitales. These fungi display complex patterns of host-shifts and co-speciation among arthropods, grasses and subterranean ascomycetes. Many of these fungi are potential biological control agents. A better understa nding of their phylogenetic history will have both predictive and diagnostic consequences towards the selection and use of entomopathogenic fungi as biological control agents.
A large amount of nucleotide sequence data is produced by researchers in our lab. These data allow us to contribute to both theoretical and practical aspects of systematics that extend beyond mycology. Such areas of research include combining and partitioning data sets, molecular clock and evolutionary rate analyses, character mapping, nuclear versus mitochondrial evolution and molecular evolution of ribosomal DNA and other coding regions.