Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: August 1, 2001
Publication Date: N/A
Technical Abstract: Rice blast (Pyricularia grisea (Cooke) Sacc.) is one of the most important fungal diseases of cultivated rice (Oryza sativa L.). Accessions of O. barthii, O. meridionalis, O. nivara and O. rufipogon were backcrossed with the long-grain experimental line, RU9401188, and the medium grain rice cultivar, 'Bengal'. To date, backcrosses have been made through the BC3 generation. Seedlings grown from self seed of the parental lines, F1, BC1 and BC2 progenies, were inoculated with seven individual blast races commonly found in U.S. rice production areas. While resistance to the individual races was identified in the parents and their progeny, none was identified as being resistant to all races. DNA was extracted from leaves of the parental lines, F1, BC1 and BC2 progenies. To date, the DNAs have been analyzed using microsatellite markers from each chromosome arm of rice. Additional markers were used for the chromosome arms which contained known blast resistance genes (Pi-genes). Microsatellite markers verified that chromosome segments from the Oryza sp. parent were still present in the BC2 progenies. As other microsatellite markers linked to known Pi-genes are reported, they will be screened. Also, Pi-gene specific primers will be used as they become available.