Cigar line Beinhart 1000-1 has effective durable resistance to black shank(BS) and is considered one of the most resistant sources in tobacco(Nicotiana tabacum L.). To investigate the inheritance and identification of...Cigar line Beinhart 1000-1 has effective durable resistance to black shank(BS) and is considered one of the most resistant sources in tobacco(Nicotiana tabacum L.). To investigate the inheritance and identification of stable quantitative trait loci(QTL) for BS response, F2,BC1 F2 individuals and BC1 F2:3 lines were produced from a cross between Beinhart 1000-1 and Xiaohuangjin 1025. Two major quantitative trait loci(M-QTL) named qBS7 and qBS17 were repeatedly detected under different conditions. QTL qBS7 was mapped to the region between PT30174 and PT60621 and explained 17.40%–25.60% of the phenotypic variance under different conditions. The other QTL qBS17 in interval PT61564–PT61538 of linkage group 17 was detected in a BC1 F2 population in the field and in BC1 F2:3 in both the field and at the seedling stage, explaining 6.90% to 11.60% of the phenotypic variance. The results improve our understanding of the inheritance of resistance to BS and provide information that can be used in marker-assisted breeding.展开更多
The bacterium Xanthomonas oryzae pv.Oryzae(Xoo)causes blight in rice worldwide,resulting in signifi-cant crop loss.However,no gene underlying a quantitative trait locus(QTL)for resistance against Xoo has been cloned y...The bacterium Xanthomonas oryzae pv.Oryzae(Xoo)causes blight in rice worldwide,resulting in signifi-cant crop loss.However,no gene underlying a quantitative trait locus(QTL)for resistance against Xoo has been cloned yet.Here,we report the map-based cloning of a QTL,in which the NBS8R gene confers quantitative resistance to Xoo.NBS8R encodes an NB-ARC protein,which is involved in pathogen/microbe-associated molecular pattern-triggered immunity and whose expression is regulated by non-TAL effector XopQ-inducible Osa-miR1876 through DNA methylation.Sequence analysis of NBS8R in wild rice species and rice cultivars suggests that the Osa-miR1876 binding sites in the 5'UTR of NBS8R are inserted by chance and have undergone variations with Osa-miR1876 throughout evolution.The inter-action between NBS8R and XopQ-inducible Osa-miR1876 is partially in keeping with the zigzag model,revealing that quantitative genes may also follow this model to control the innate immune response or basal disease resistance,and may prove valuable in utilizing the existing landraces that harbor the NBS8R gene but with no Osa-miR1876 binding site in rice breeding for bacterial blight resistance.展开更多
基金supported by grants from the Agricultural Science and Technology Innovation Program (ASTIP-TRIC01)National Natural Science Foundation of China (31571738)
文摘Cigar line Beinhart 1000-1 has effective durable resistance to black shank(BS) and is considered one of the most resistant sources in tobacco(Nicotiana tabacum L.). To investigate the inheritance and identification of stable quantitative trait loci(QTL) for BS response, F2,BC1 F2 individuals and BC1 F2:3 lines were produced from a cross between Beinhart 1000-1 and Xiaohuangjin 1025. Two major quantitative trait loci(M-QTL) named qBS7 and qBS17 were repeatedly detected under different conditions. QTL qBS7 was mapped to the region between PT30174 and PT60621 and explained 17.40%–25.60% of the phenotypic variance under different conditions. The other QTL qBS17 in interval PT61564–PT61538 of linkage group 17 was detected in a BC1 F2 population in the field and in BC1 F2:3 in both the field and at the seedling stage, explaining 6.90% to 11.60% of the phenotypic variance. The results improve our understanding of the inheritance of resistance to BS and provide information that can be used in marker-assisted breeding.
基金grants from the Ministry of Science and Technology of China(2016YFD0101801)the Ministry of Agricultur of China(2016ZX08009003 and 2016ZX08009001)the National Natural Science Foundation of China(31900383 and 31971911).
文摘The bacterium Xanthomonas oryzae pv.Oryzae(Xoo)causes blight in rice worldwide,resulting in signifi-cant crop loss.However,no gene underlying a quantitative trait locus(QTL)for resistance against Xoo has been cloned yet.Here,we report the map-based cloning of a QTL,in which the NBS8R gene confers quantitative resistance to Xoo.NBS8R encodes an NB-ARC protein,which is involved in pathogen/microbe-associated molecular pattern-triggered immunity and whose expression is regulated by non-TAL effector XopQ-inducible Osa-miR1876 through DNA methylation.Sequence analysis of NBS8R in wild rice species and rice cultivars suggests that the Osa-miR1876 binding sites in the 5'UTR of NBS8R are inserted by chance and have undergone variations with Osa-miR1876 throughout evolution.The inter-action between NBS8R and XopQ-inducible Osa-miR1876 is partially in keeping with the zigzag model,revealing that quantitative genes may also follow this model to control the innate immune response or basal disease resistance,and may prove valuable in utilizing the existing landraces that harbor the NBS8R gene but with no Osa-miR1876 binding site in rice breeding for bacterial blight resistance.
