Author
CHAUHAN, RAJINDER - UNIVERSITY OF WISCONSIN | |
FARMAN, MARK - UNIVERSITY OF KENTUCKY | |
RONALD, P - UNIVERSITY OF CA AT DAVIS | |
Leong, Sally |
Submitted to: American Phytopathological Society
Publication Type: Abstract Only Publication Acceptance Date: 4/15/1997 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Management of rice blast through host resistance is considered to be one of the most economically viable, environmentally friendly and sustainable strategies. We are cloning a rice blast resistance gene in an indica rice line, CO39, corresponding to avirulence gene AVR1-CO39, which has been cloned. Two strategies, i.e. positional cloning and degenerate PCR-based methods, are being used. Fifteen mirosatellite markers mapping to four rice chromosomes 1, 6, 11 & 12, which are known to carry most of the known disease resistance genes, were tested for polymorphism between indica rice lines, CO39 (resistant) and 51583 (susceptible), which have been used as differential host lines for genetic analysis and cloning of avirulence gene AVR1-CO39 of M. grisea. Co-segregation of polymorphic RM markers with resistance/susceptibility was tested using bulked segregant analysis as well as individual F3 families. Microsat marker, RM202, and RFLP marker, RG247 close to RM202, located on chromosome 11, co- segregated with blast resistance in 30R/6S F3 families as well as bulks. Degenerate oligonucleotide primers designed from the conserved regions of both the leucine-rich repeats and serine-threonine kinase domains of Xa21, have amplified 850bp fragments in CO39 and 51583. The PCR products were cloned and categorized into six groups on the basis of size and sequence analysis. The segregation behavior of these loci is being studied in segregating populations of crosses between CO39X51583. |