普通野生稻抗细菌性条斑病基因的遗传分析与定位

Genetic analysis and mapping of bacterial leaf streak resistance genes in Oryzae rufipogon Griff

【目的】挖掘水稻Oryza sativa L.抗细菌性条斑病(Bacterial leaf streak, BLS)主效基因,为丰富水稻抗病基因资源和培育水稻抗病品种奠定基础。【方法】建立作图群体,对普通野生稻Oryza rufipogon Griff抗源‘DY19’抗BLS的基因采用集团分离分析法进行遗传分析,用SSR分子标记对其抗病基因bls2进行初步定位。【结果】F2群体中抗病与感病单株符合1∶3的理论分离比例,说明普通野生稻抗源‘DY19’的抗BLS符合单基因遗传模式,受1对主效隐性基因bls2控制。初步将该基因定位在第2号染色体分子标记SL03(23 474 851 bp)与SL04(24 484 154 bp)之间约4 cM区域内,这是一个新的抗BLS基因位点。【结论】普通野生稻抗源‘DY19’对细菌性条斑病的抗性受1对新的主效隐性基因bls2控制,为进一步的精细定位提供参考。

【Objective】To exploit major resistance genes of rice(Orjza xaNva L.)to bacterial leaf streak(BLS),and provide a basis for enriching rice disease resistant gene resources and breeding resistant cultivars.【Method】Constructing a mapping population,we conducted genetic analyses of BLS resistance genes in Griff‘DY19’using the bulk segregant analysis method,and preliminarily mapped the BLS resistance gene bls2 through SSR molecular markers.【Result】The ratio of resistant and susceptible individual plants in F2 population was in accordance with the theoretical segregation ratio of 1∶3,which showed that the resistance gene to BLS in O.rufipogon SDY195 was consistent with single gene genetic pattern and controlled by one pair of main recessive gene bls2.This gene was mapped in a 4 cM region between molecular markers SL03(23 474 851 bp)and SL04(24 484 154 bp)on the second chromosome.This locus was a new disease resistance locus.【Conclusion】The BLS resistance in O.‘DY19’is controlled by one pair of new major recessive gene bls2.It can provide a reference for further fine mapping.