ARS | Publication request: Identification of SSR markers for a broad-spectrum blast resistance gene Pi-20(t) for marker-assisted breeding

Submitted to: Molecular Breeding
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 29, 2008
Publication Date: April 19, 2008
Citation: Li, W., Lei, C., Cheng, Z., Jia, Y., Huang, D., Liu, Z., Wang, J., Shi, K., Zhang, X., Su, N., Guo, X., Zhai, H., Wan, J. 2008. Identification of SSR markers for a broad-spectrum blast resistance gene Pi-20(t) for marker-assisted breeding. Molecular Breeding. 22:141-149.

Technical Abstract: The Pi-20(t) gene in rice confers broad-spectrum resistance against diverse pathotypes (races) of Magnaporthe oryzae (formerly Magnaporthe grisea) in China. Two flanking, and three co-segregating SSR markers nearby the centromere region of chromosome 12 for Pi-20(t) were identified using 526 extremely susceptible F2 plants derived from a cross of Asominori, an extremely susceptible cultivar with a highly resistant cultivar, IR24. OSR32 was mapped at 0.2cM of Pi-20(t) at one side and RM28050 was mapped at 0.4cM of Pi-20(t) at another side. Three SSR markers (RM1337, RM5364 and RM7102) were found to co-segregate with Pi-20(t). RM1337 and RM5364 were found to be reliable markers to tag resistance conditioned by Pi-20(t) in a wide range of elite rice germplasm in China. Thus, these two SSR markers are useful in marker-assisted incorporation of Pi-20(t) into advanced breeding lines for achieving durable and broad spectra of resistance to M. oryaze.