Fine mapping and identification of blast resistance gene Pi-hk1 in a broad-spectrum resistant japonica rice landrace

Phytopathology. 2013 Nov;103(11):1162-8. doi: 10.1094/PHYTO-02-13-0044-R.

Abstract

One Japonica rice landrace, Heikezijing, from the Taihu Lake region of China, exhibits broad-spectrum resistance to rice blast. As characterized in our previous research, a main-effect resistance (R) gene, Pi-hk1, in Heikezijing against five isolates (GD10-279a, JS2004-141-1, JS2004-185, JS90-78, and Hoku1) was roughly mapped on the long arm of chromosome 11. To fine map Pi-hk1, one recombinant inbred line (RIL), RIL72 (F2:8), from the cross between Heikezijing and blast-susceptible variety Suyunuo, was further crossed and backcrossed with Suyunuo to produce a BC1F2 population of 477 individuals. Inoculation experiments with the representative isolate Hoku 1 indicated that RIL72 carries a single dominant R gene for blast resistance. With the help of advanced BC1F3 (915 plants), BC1F4 (4,459 plants), and BC1F5 (2,000 plants) mapping populations, Pi-hk1 was finally mapped to a 107-kb region between molecular markers P3586 and ILP3, and co-segregated with the markers P4098, RM7654, and P4099. By sequence analysis of Heikezijing bacterial artificial chromosome clones covering Pi-hk1 region, 16 predicted genes were identified within this region, including three nucleotide-binding site leucine-rich repeat candidate genes. These results provide essential information for cloning of Pi-hk1 and its application in rice breeding for broad-spectrum blast resistance by marker-assisted selection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Breeding
  • China
  • Chromosome Mapping
  • Chromosomes, Artificial, Bacterial
  • Disease Resistance / genetics*
  • Gene Expression Regulation, Plant
  • Magnaporthe / pathogenicity*
  • Oryza / genetics*
  • Oryza / immunology
  • Oryza / microbiology
  • Plant Diseases / immunology*
  • Plant Diseases / microbiology
  • Plant Proteins / genetics*

Substances

  • Plant Proteins