Open AccessLocalizing the Bacterial Blight Resistance Gene, Xa22(t), to a 100-Kilobase Bacterial Artificial Chromosome
Author(s) -
Chuntai Wang,
Mingpu Tan,
Xin Xu,
Wen Geyi,
Zhang Duanpin,
Xinghua Lin
Publication year - 2003
Publication title -
phytopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.264
H-Index - 131
eISSN - 1943-7684
pISSN - 0031-949X
DOI - 10.1094/phyto.2003.93.10.1258
Subject(s) - biology , genetics , locus (genetics) , bacterial artificial chromosome , gene mapping , population , restriction fragment length polymorphism , genetic linkage , xanthomonas oryzae , gene , genetic marker , chromosome , genotype , genome , demography , sociology
The rice bacterial blight resistance gene, Xa22(t), provides resistance to a broad spectrum of Xanthomonas oryzae pv. oryzae isolates. Here, we localize the gene to a small 100-kb fragment of chromosome 11 by a combination of genetic recombination analysis and physical mapping. Mapping was done with two F 2 populations from the cross between Zhachanglong and Zhenzhuai. The first population consisted of 248 random individuals and 404 highly susceptible individuals selected from an F 2 population of more than 2,000 individuals and was used to construct a linkage map around the Xa22(t) locus. For the second F 2 population, 7,680 plants were examined with simple sequence repeat markers flanking the Xa22(t) locus to identify recombinants useful for fine-genetic mapping. Two large-insert bacterial artificial chromasome (BAC) libraries (from cvs. Teqing and Minghui63) were screened with a marker (R1506) which cosegregated perfectly with Xa22(t) in the first population. Restriction mapping of the resulting BAC clones enabled a physical map of the area to be constructed, and subclones from the BAC clones provided additional restriction fragment length polymorphism probes which could be placed on the fine-structure genetic map using the recombinants from the second mapping population. The Xa22(t) locus was mapped to a ≈ 100-kb interval delimited by the R1506 marker and a subclone from the M3H8 BAC clone.