Submitted to: American Phytopathological Society Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: May 1, 2006
Publication Date: July 29, 2006
Citation: Jia, Y., Fjellstrom, R.G., Jia, Melissa H., Yan, W., Rutger, J.N., McClung, A.M. 2006. Development and characterization of rice mutants altered in the rice blast resistant gene pi-ta-mediated disease resistance pathway [abstract]. American Phytopathological Society Annual Meeting. Phytopathology. 96:S54. Interpretive Summary: Abstract only - interpretive summary not required
Technical Abstract: The Pi-ta gene in rice prevents the infection of the fungal pathogen Magnaporthe oryzae races containing the corresponding avirulence gene AVR-Pita. The Pi-ta gene encodes a putative cytoplasmic protein with a centrally localized nucleotide binding site and a leucine rich domain. AVR-Pita is a metalloprotease that is predicted to interact with the product of the Pi-ta gene inside plant cells triggering an active defense response. The US rice cultivar, Katy, containing the Pi-ta gene, was treated with ethyl methyl sulfate, fast neutrons and gamma irradiations to create mutations in the components of Pi-ta-mediated resistance. Forty-two blast susceptible mutants were collected from a total of 15,000 M1 random panicles. The disease susceptibility was verified in 5 M6 mutants that were confirmed to be from Katy using simple sequence repeat markers. To identify natural Pi-ta mutants, 181 rice accessions were identified to contain the Pi-ta gene from a core collection of rice germplasm using a Pi-ta single nucleotide length polymorphism marker. Subsequent inoculations with M. oryzae isolates containing AVR-Pita identified 4 susceptible mutants. Progress on molecular genetic analysis of the Pi-ta-mediated signaling components in these induced and natural mutants will be presented.