Open AccessComplex genetic networks underlying the defensive system of rice ( Oryza sativa L.) to Xanthomonas oryzae pv. oryzae
Author(s) -
Z. K. Li,
Muhammad Arif,
Dexing Zhong,
Bin Ying Fu,
Jianlong Xu,
J. Domingo-Rey,
Jauhar Ali,
C. H. M. Vijayakumar,
Shuxun Yu,
G. S. Khush
Publication year - 2006
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.0507492103
Subject(s) - xanthomonas oryzae , xanthomonas oryzae pv. oryzae , biology , oryza sativa , epistasis , genetics , allele , oryza , xanthomonas , gene , genetic diversity , population , demography , sociology
Complete resistance (CR) and partial resistance (PR) of rice (Oryza sativa L.) to its bacterial pathogen,Xanthomonas oryzae pv.oryzae (Xoo ), was genetically dissected by using 2 mapping populations and 10Xoo races. Two CR genes, 50 quantitative resistance loci, and 60 digenic interactions were identified, which showed various degrees of race specificity to theXoo races. The complex epistasis between these loci led us to the discovery of complex genetic networks underlying the rice defensive system toXoo . The networks consisted of two major components: one representing interactions between alleles at the R loci of rice and alleles at the corresponding avirulence loci ofXoo for CR and the other comprising interactions between quantitative resistance loci in rice and their corresponding aggressiveness loci inXoo for PR. The race specificity of PR and its strong genetic overlap with CR indicate that PR is essentially “weaker” CR. The genetic networks discovered are expected to maintain a high level of the allelic diversity at avirulent loci in the pathogen by stabilizing selection, which may maintain a high allelic diversity at R loci in the host by the frequency-dependent selection.