XVI International Botanical Congess

The species M. grisea comprises pathogens of the grass family. Studies on genome organization of M. grisea have led to the development of high density genetic maps, electrophoretic karyotypes, a BAC contig of the smallest chromosome, and considerable information about the repetitive DNA content of the organism. The genomic content of specific repeats and their genomic organization has enabled different host-specific forms to be distinguished from one another and clonal lineages to be defined. Analysis of orthologs and paralogs of host- and cultivar-specificity genes provide interesting insights into the evolution of the species vis a vis the host. Physical mapping and map-based cloning studies point to considerable variation in the relationship of genetic to physical distance across the genome. Efforts to determine the complete nucleotide sequence of the fungal nuclear genome are underway.