Project name: Bipolaris maydis

Description: Cochliobolus heterostrophus (asexual state: Bipolaris maydis) is a pathogen of corn and is responsible for the disease Southern Corn Leaf Blight. Currently this fungus does not cause economically significant crop losses but did in the past when corn carrying T-cms was widely planted. Corn with mitochondrial DNA carrying T-cms is very sensitive towards race T but not race O of the fungus. C. heterostrophus race T produces a host selective toxin (HST), called T-toxin (a family of linear polyketides), which makes race T highly virulent on T-cms corn. The combination of race T of the fungus and the host carrying T-cms was responsible for the destruction of more than 15% of the U.S. maize crop in 1969-70. Prior to 1970, C. heterostrophus was known as an endemic pathogen of minor economic importance in the U.S., first described in 1925 by Drechsler. This version of the pathogen (race O) is mildly virulent on both T- and N-cytoplasm corn. C5, the sequenced race O strain is a highly inbred line from a backcross series.In the field, the sexual stage is rarely observed but can be easily induced in the laboratory. Efficient homologous recombination between transforming DNA and the target genomic sequence provides efficient tractability for genetic analysis, making this an excellent model organism for functional analyses.

Last updated: 2010-01-06