Submitted to: Arkansas Agricultural Experiment Station Research Series
Publication Type: Experiment Station
Publication Acceptance Date: 6/27/2006
Publication Date: 8/8/2006
Citation: Singh, P., Jia, Y., Boza, E.J., Correll, J.C., Lee, F.N. 2006. Development of a molecular marker from the rice blast avirulence gene AVR-Pita for surveillance of durable rice blast resistance conferred by Pi-ta in Arkansas. In: Norman, R.J., Meullenet, J.-F., Moldenhauer, K.A.K.., editors. B.R. Wells Rice Research Studies 2005 Arkansas Agricultural Experiment Station Research Series 540. p. 152-159. Interpretive Summary:
Technical Abstract: In Arkansas, a major resistance gene Pi-ta in rice has been deployed effectively to prevent blast disease. Currently, the US cultivars, Katy, Madison, Kaybonnet, Drew, Cybonnet and Ahrent were confirmed to contain the resistance gene Pi-ta. Pi-ta is effective only when blast pathogen Magnaporthe oryzae isolates contain the corresponding avirulence gene AVR-Pita. The effectiveness of resistance conferred by Pi-ta is challenged by the instability of the AVR-Pita gene. To facilitate the examination of resistance stability of mediated by Pi-ta, the existence of the AVR-Pita allele from a set of races / isolates of M. oryzae were studied using AVR-Pita gene specific primers in polymerase chain reaction (PCR). M. oryzae isolates failed to infect rice cultivars containing a 1086 bp PCR product using primers YL149 and YL169; whereas those isolates that lacked the 1086 bp PCR product regained their abilities to infect rice cultivars that contain Pi-ta. Sequence analysis of these PCR products revealed highly conserved proteins that are similar to the AVR-Pita protein. Thus, DNA primer YL149 and YL169 is a reliable DNA marker to survey the durability of resistance conferred by Pi-ta.