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Project 1: Genetics and Population Studies of Fusarium graminearum: Increase collection size and diversity in terms of geographic and host origin. Determine if identified phylogenetic lineages warrant recognition at the species level. Determine relatedness of domestic and foreign populations. Determine if inter-lineage hybrids occur under field conditions.<P> Project 2: Taxonomy and Population Studies of Fusarium spp. Increase collection size and diversity in terms of geographic and host origin. Develop species-specific PCR markers for major species from maize and sorghum, and standard mating type tester strains for all species for which a sexual stage can be identified in the laboratory. Describe new species and new mating populations.<P> Project 3: Genetics of Vegetative Compatibility: Map multiple vic loci in F. graminearum and F. verticillioides. Clone multiple vic loci and identify the portion of the coding sequence responsible for the interaction that results in the killing reaction. <P>Project 4: Fusarium Laboratory Workshops: Enable attendance by up to 50 participants at KSU by upgrading infrastructure in teaching labs to prevent the need from using large amounts of research equipment to run the class. Develop standard written protocols and timelines for running a workshop that can be used by those organizing a class not being held at KSU. Maintain quality and diversity of instructors from outside KSU who agree to participate in teaching the course. Establish the laboratory manual based on the techniques taught in the course as the standard for the area.
Non-Technical Summary: We will test 9 genetic lines of F. graminearum (Gibberella zeae) to determine if they are separate species, which could impact trade and quarantine regulations, by using molecular and classical genetics. We will confirm the presence of interlineage hybrids in Australia, Asia and South America and quantify population variation and genetic exchange. Fusarium species identification requires large global collections of strains. We use cross fertility to define species and then develop molecular and morphological markers as diagnostics. We have identified three new species, and have several others still to describe. We will increase the number of strains examined (enlarging our worldwide collection of > 14,000) and identify DNA fragments that can be used as diagnostics. Vegetative compatibility is the means by which fungi distinguish self from non-self. The basic gene identification strategy is to place putative vic loci on classical genetic maps and identify the genes by position on genomic sequences. When a vic allele is identified that sequenceA one-week class on the biology of Fusarium. Identification of Fusarium spp. is essential for researchers and diagnosticians. Since 2000, there have been nine instructors and > 230 participants worldwide. The workshop is held in odd years at KSU and in even years outside the USA is used to identify other alleles. <P> Approach: Project 1: Genetics and Population Studies of Fusarium graminearum We will test 9 phylogenetic lineages of F. graminearum (Gibberella zeae) to determine if they warrant description as species by making diallelic crosses amongst identified lineage tester strains, by crossing lineage tester strains with mutants that have a partially inactivated mating type locus, and by determining whether fertility and either DNA sequence or AFLP-based lineage-associated markers cosegregate. We will use both DNA sequence and AFLP markers to determine whether field strains from Australia, Asia and South America are interlineage hybrids, and identify additional markers that can be used to track/identify lineage. We will calculate gene frequencies, estimate population differentiation, and gene flow. Our AFLP markers give us greater genome-wide information than does the sequencing of individual genes, and is more sensitive to introgression between lineages, especially in backcross generations. Project 2: Taxonomy & Population Studies of Fusarium spp.: Fusarium species identification has been a major problem for > 100 years, and differences between isolates from native and agricultural ecosystems hold key insights into the evolution of plant pathogens. These questions require relatively large collections of strains of a global nature. We use a biological species concept to define species and then add molecular and morphological markers to enable more rapid diagnoses. We have identified and described three new species, and have identified strains that belong to at least two other undescribed species, with most of our attention focused on sorghum and natural grasslands. We will increase the number of strains examined (and enlarge the present worldwide collection of > 14,000 isolates), subclone and sequence conserved differential AFLP fragments, and design PCR primers that can be used to specifically amplify these fragments. Project 3: Genetics of Vegetative Compatibility: Vegetative compatibility is the mechanism by which fungi distinguish self from non-self. The basic gene identification strategy is the same for both F. verticillioides and F. graminearum. Regions containing putative vic loci will be placed on classical genetic maps. Open reading frames in these regions will be cloned and tested for vic locus activity. Once a vic allele is identified that sequence will be used to identify other alleles.Project 4: Fusarium Laboratory Workshops: one-week full-time class on the biology of Fusarium. Accurate identification of Fusarium spp. is essential for researchers and diagnosticians in air quality laboratories, medical and plant pathological diagnostic clinics, universities and governmental laboratories. Since 2000, 9 people have served as instructors and there have been > 230 participants from all continents. It is one of the few times when representatives of most of the species in the genus can be seen side-by-side and integrates molecular biology, genetics, mycotoxicology, phylogenetics and morphological species identifications into a single presentation. The workshop is held in odd years at KSU in Manhattan and in even years elsewhere in the world.