Success in conventional breeding for resistance to mycotoxin-producing or other phytopathogenic fungi is dependent on the availability of resistance gene(s) in the germplasm.Even when it is available,breeding for dise...Success in conventional breeding for resistance to mycotoxin-producing or other phytopathogenic fungi is dependent on the availability of resistance gene(s) in the germplasm.Even when it is available,breeding for disease-resistant crops is very time consuming,especially in perennial crops such展开更多
The transcriptome-wide gene expression was compared between susceptible and resistant Chinese cabbage cultivars to identify genes that contributed to clubroot resistance. A higher number of differentially expressed ge...The transcriptome-wide gene expression was compared between susceptible and resistant Chinese cabbage cultivars to identify genes that contributed to clubroot resistance. A higher number of differentially expressed genes were detected in susceptible cultivars than in resistant cultivars. Fifty-six genes involved in cell wall modification, hormone signaling, root marphogenesis, nematodes response and cell proliferation were uniquely expressed in the resistant cultivars. Among them, 27 genes were involved in cell wall modification and hormone signaling, indicating that genes in these two types might play a vital role in the defense response to pathogen infection.展开更多
Resistance genes enable plants to fight against plant pathogens. Plant resistance genes （R gene） are organized complexly in genome. Some resistance gene sequence data enable an insight into R gene structure and gene...Resistance genes enable plants to fight against plant pathogens. Plant resistance genes （R gene） are organized complexly in genome. Some resistance gene sequence data enable an insight into R gene structure and gene evolution. Some sites like Leucine-Rich Repeat （LRR） are of specific interest since homologous recombination can happen. Crossing over, transposon insertion and excision and mutation can produce new specificity. Three models explaining R gene evolution were discussed. More information needed for dissection of R gene evolution though some step can be inferred from genetic and sequence analysis.展开更多
Background:Verticillium wilt,caused by the soil-borne fungus of Verticillium dahliae Kleb.,is one of the most devastating diseases of cotton.The complex mechanism underlying cotton resistance to Verticillium wilt rema...Background:Verticillium wilt,caused by the soil-borne fungus of Verticillium dahliae Kleb.,is one of the most devastating diseases of cotton.The complex mechanism underlying cotton resistance to Verticillium wilt remains uncharacterized.Identifying an endogenous resistance gene may be helpful to control this disease.Previous studies revealed that succinate dehydrogenase(SDH)is involved in reactive oxygen species(ROS)-induced stress signaling pathway that is likely to be triggered by salicylic acid(SA).Here,through the metabolomics and differential expression analyses in wilt-inoculated cotton(Gossypium hirsutum),we noticed that Gh SDH1–1 gene in cotton may play an important role in the resistance to V.dahlia.Then we reported Gh SDH1–1 gene and its functional analysis in relation to the resistance of cotton to V.dahliae.Results:The Gh SDH1–1 gene in cotton root was significantly up-regulated after V.dahlia inoculation,and its expression level peaked at 12 and 24 h post-infection.SA can also induce the up-regulation of Gh SDH1–1.Additionally,the functional analysis showed that Gh SDH1–1-silenced cotton was more susceptible to V.dahliae than the control because of the significant decrease in abundance of immune-related molecules and severe damage to the SA-signaling pathway.In Arabidopsis thaliana,high expression of Gh SDH1–1 conferred high resistance to V.dahliae.Arabidopsis that overexpressed Gh SDH1–1 had higher resistance to V.dahliae infection compared with the wild-type.Conclusions:Our findings provide new insights into the role of Gh SDH1–1;it positively regulates cotton resistance to Verticillium wilt.The regulatory mechanism of Gh SDH1–1 is closely related to SA-related signaling pathway.展开更多
Total RNA from leaves of Poapratensis cultivars under drought stress was extracted for reversing transcription to cDNA and then cDNA as template for PCR reaction by designing primer of cds of Hordeum valgare HVA1 drou...Total RNA from leaves of Poapratensis cultivars under drought stress was extracted for reversing transcription to cDNA and then cDNA as template for PCR reaction by designing primer of cds of Hordeum valgare HVA1 drought resistance gene from GenBank. The amplified products were positive recon identified by using procedures of recovery, connection, transformation and enzyme separation. The length of cloned gene sequence was 324 bp, identity reached 79.27% with Barley HVA1 gene that meaned the cloned gene sequence was the partial HVA1 gene of Poapratensis.展开更多
Southern corn rust(SCR) caused by Puccinia polysora Underw and maize stalk rot caused by Pythium inflatum Matthews(MSR-2) are two destructive diseases of maize(Zea mays L.) in China.Our previous studies indicated that...Southern corn rust(SCR) caused by Puccinia polysora Underw and maize stalk rot caused by Pythium inflatum Matthews(MSR-2) are two destructive diseases of maize(Zea mays L.) in China.Our previous studies indicated that maize inbred line Qi319 is highly resistant to SCR but susceptible to MSR-2,while inbred line 1145 is highly resistant to MSR-2 but susceptible to SCR.The SCR resistant gene(RppQ) in Qi319 and MSR-2 resistant gene(Rpi1) in 1145 have been mapped on chromosome 10 and 4 respectively.In this research,through marker-assisted selection(MAS) with the molecular markers,bnlg1937 tightly linked to Rpi1 and phi041 tightly linked to RppQ,pyramid breeding of the two kinds of disease resistant genes were carried out from the year of 2003 to 2007.Two homozygotic inbred lines of F5 generation,DR94-1-1-1 and DR36-1-1-1 were identified.MAS result suggested DR94-1-1-1 and DR36-1-1-1 contained the two resistance genes RppQ and Rpi1.Field inoculation tests confirmed their high resistance to the two diseases.In addition,field investigation indicated that the two selected inbred lines,particularly DR94-1-1-1,had excellent agronomic traits such as plant height,ear height and yield-relating traits including ear length,ear diameter,ear weight,kernels per ear,kernels per row and kernel weight per ear.The two selected inbred lines DR94-1-1-1 and DR36-1-1-1 can either be directly developed into commercial variety or used as immediate donors of SCR and MSR resistance breeding programs in maize.展开更多
Plants have developed a complicated defense mechanism during evolution to resist the harmful pathogens they encountered.The mechanism involves the interaction of the plant resistance(R)
Escherichia coli O157 : H7 is a foodborne pathogen that poses a major threat to public health. Epidemiologic investigations have identified dairy cows, especially calves, are the principal reservoir of E. coli O157 : ...Escherichia coli O157 : H7 is a foodborne pathogen that poses a major threat to public health. Epidemiologic investigations have identified dairy cows, especially calves, are the principal reservoir of E. coli O157 : H7. In this study, based on the results, E. coli O157 : H7 was the main cause of E. coli disease outbreak in late October, 2015, and more than 90% of newborn calves died of serious diarrhea. Through further experiments, the drug sensitivity and resistance of the strain, the expression of the virulence gene and virulence pathogenicity were studied. E. coli O157 : H7 isolates were resistant to 12 antibiotics including penicillin, tetracycline and ampicillin, and were sensitive to eight antibiotics including cefoperazone, ceftazidime and amikacin. Resistance genes included tetB, strB, aadB, aphA, floR, TEM and virulence genes included stx1, eaeA and hlyA. Using specific pathogen free mice, the result showed that the isolate was pathogenic with a median lethal dose of 7.9×107 CFU · mL-1. This study described the pathogenesis and clinical manifestations of E. coli O157 : H7 infection. These results guided the use of antibiotics in prevent and control of bacterial infections in the future.展开更多
An about 1.40 Kb target gene fragment was yielded by PCR amplification with the plasmid pRB 129,which was identified by restriction enzyme digestion that the PCR product was TUB2 gene.The gene was digested by the rest...An about 1.40 Kb target gene fragment was yielded by PCR amplification with the plasmid pRB 129,which was identified by restriction enzyme digestion that the PCR product was TUB2 gene.The gene was digested by the restriction enzyme and was linked with pTA plasmid to construct pTA TUB2 plasmid.The plasmid was transformed into Chaetomium spp.by PEG method and the transformation rate was 27/(2×10 5) and it is nine times higher than that of pRB 129.The transformants can grow on the PDA containing 1 000 μg·mL -1 carbendazim,which is 1 000 times higher than the original Chaetomium spp.The resistance was stable after 10 times transfer on non selective medium.展开更多
The leaf mould resistance gene Cf-10 on tomato confered resistant or immune to all prevalent physiological races of Cladosporium fulvum presented in three northeastern provinces of China in inoculation test. In order ...The leaf mould resistance gene Cf-10 on tomato confered resistant or immune to all prevalent physiological races of Cladosporium fulvum presented in three northeastern provinces of China in inoculation test. In order to better utilize Cf-10 gene in a marker-assisted selection program and to permit the pyramiding of one or several resistance genes in a cultivar, tightly linked SSR and AFLP markers were obtained by the bulked segregant analysis method. One SSR marker and three AFLP markers were identified linked to Cf-10 gene, with the distance of 9.73, 5.8, 8.5, and 10.6 cM, respectively. These markers will facilitate the selection of resistant tomato germplasm containing Cf-10 gene.展开更多
文摘Success in conventional breeding for resistance to mycotoxin-producing or other phytopathogenic fungi is dependent on the availability of resistance gene(s) in the germplasm.Even when it is available,breeding for disease-resistant crops is very time consuming,especially in perennial crops such
基金Supported by the National Key Research and Development Project(2017YFD0101803)
文摘The transcriptome-wide gene expression was compared between susceptible and resistant Chinese cabbage cultivars to identify genes that contributed to clubroot resistance. A higher number of differentially expressed genes were detected in susceptible cultivars than in resistant cultivars. Fifty-six genes involved in cell wall modification, hormone signaling, root marphogenesis, nematodes response and cell proliferation were uniquely expressed in the resistant cultivars. Among them, 27 genes were involved in cell wall modification and hormone signaling, indicating that genes in these two types might play a vital role in the defense response to pathogen infection.
文摘Resistance genes enable plants to fight against plant pathogens. Plant resistance genes （R gene） are organized complexly in genome. Some resistance gene sequence data enable an insight into R gene structure and gene evolution. Some sites like Leucine-Rich Repeat （LRR） are of specific interest since homologous recombination can happen. Crossing over, transposon insertion and excision and mutation can produce new specificity. Three models explaining R gene evolution were discussed. More information needed for dissection of R gene evolution though some step can be inferred from genetic and sequence analysis.
基金supported by the National Natural Science Foundation of China(31701479)。
文摘Background:Verticillium wilt,caused by the soil-borne fungus of Verticillium dahliae Kleb.,is one of the most devastating diseases of cotton.The complex mechanism underlying cotton resistance to Verticillium wilt remains uncharacterized.Identifying an endogenous resistance gene may be helpful to control this disease.Previous studies revealed that succinate dehydrogenase(SDH)is involved in reactive oxygen species(ROS)-induced stress signaling pathway that is likely to be triggered by salicylic acid(SA).Here,through the metabolomics and differential expression analyses in wilt-inoculated cotton(Gossypium hirsutum),we noticed that Gh SDH1–1 gene in cotton may play an important role in the resistance to V.dahlia.Then we reported Gh SDH1–1 gene and its functional analysis in relation to the resistance of cotton to V.dahliae.Results:The Gh SDH1–1 gene in cotton root was significantly up-regulated after V.dahlia inoculation,and its expression level peaked at 12 and 24 h post-infection.SA can also induce the up-regulation of Gh SDH1–1.Additionally,the functional analysis showed that Gh SDH1–1-silenced cotton was more susceptible to V.dahliae than the control because of the significant decrease in abundance of immune-related molecules and severe damage to the SA-signaling pathway.In Arabidopsis thaliana,high expression of Gh SDH1–1 conferred high resistance to V.dahliae.Arabidopsis that overexpressed Gh SDH1–1 had higher resistance to V.dahliae infection compared with the wild-type.Conclusions:Our findings provide new insights into the role of Gh SDH1–1;it positively regulates cotton resistance to Verticillium wilt.The regulatory mechanism of Gh SDH1–1 is closely related to SA-related signaling pathway.
基金Supported by Committee of Nature Science Foundation of Heilongjiang Province (C0207)
文摘Total RNA from leaves of Poapratensis cultivars under drought stress was extracted for reversing transcription to cDNA and then cDNA as template for PCR reaction by designing primer of cds of Hordeum valgare HVA1 drought resistance gene from GenBank. The amplified products were positive recon identified by using procedures of recovery, connection, transformation and enzyme separation. The length of cloned gene sequence was 324 bp, identity reached 79.27% with Barley HVA1 gene that meaned the cloned gene sequence was the partial HVA1 gene of Poapratensis.
文摘Southern corn rust(SCR) caused by Puccinia polysora Underw and maize stalk rot caused by Pythium inflatum Matthews(MSR-2) are two destructive diseases of maize(Zea mays L.) in China.Our previous studies indicated that maize inbred line Qi319 is highly resistant to SCR but susceptible to MSR-2,while inbred line 1145 is highly resistant to MSR-2 but susceptible to SCR.The SCR resistant gene(RppQ) in Qi319 and MSR-2 resistant gene(Rpi1) in 1145 have been mapped on chromosome 10 and 4 respectively.In this research,through marker-assisted selection(MAS) with the molecular markers,bnlg1937 tightly linked to Rpi1 and phi041 tightly linked to RppQ,pyramid breeding of the two kinds of disease resistant genes were carried out from the year of 2003 to 2007.Two homozygotic inbred lines of F5 generation,DR94-1-1-1 and DR36-1-1-1 were identified.MAS result suggested DR94-1-1-1 and DR36-1-1-1 contained the two resistance genes RppQ and Rpi1.Field inoculation tests confirmed their high resistance to the two diseases.In addition,field investigation indicated that the two selected inbred lines,particularly DR94-1-1-1,had excellent agronomic traits such as plant height,ear height and yield-relating traits including ear length,ear diameter,ear weight,kernels per ear,kernels per row and kernel weight per ear.The two selected inbred lines DR94-1-1-1 and DR36-1-1-1 can either be directly developed into commercial variety or used as immediate donors of SCR and MSR resistance breeding programs in maize.
文摘Plants have developed a complicated defense mechanism during evolution to resist the harmful pathogens they encountered.The mechanism involves the interaction of the plant resistance(R)
文摘Escherichia coli O157 : H7 is a foodborne pathogen that poses a major threat to public health. Epidemiologic investigations have identified dairy cows, especially calves, are the principal reservoir of E. coli O157 : H7. In this study, based on the results, E. coli O157 : H7 was the main cause of E. coli disease outbreak in late October, 2015, and more than 90% of newborn calves died of serious diarrhea. Through further experiments, the drug sensitivity and resistance of the strain, the expression of the virulence gene and virulence pathogenicity were studied. E. coli O157 : H7 isolates were resistant to 12 antibiotics including penicillin, tetracycline and ampicillin, and were sensitive to eight antibiotics including cefoperazone, ceftazidime and amikacin. Resistance genes included tetB, strB, aadB, aphA, floR, TEM and virulence genes included stx1, eaeA and hlyA. Using specific pathogen free mice, the result showed that the isolate was pathogenic with a median lethal dose of 7.9×107 CFU · mL-1. This study described the pathogenesis and clinical manifestations of E. coli O157 : H7 infection. These results guided the use of antibiotics in prevent and control of bacterial infections in the future.
基金Heilongjiang Province Natural Science fund( Grant No.C0 2 0 3 )
文摘An about 1.40 Kb target gene fragment was yielded by PCR amplification with the plasmid pRB 129,which was identified by restriction enzyme digestion that the PCR product was TUB2 gene.The gene was digested by the restriction enzyme and was linked with pTA plasmid to construct pTA TUB2 plasmid.The plasmid was transformed into Chaetomium spp.by PEG method and the transformation rate was 27/(2×10 5) and it is nine times higher than that of pRB 129.The transformants can grow on the PDA containing 1 000 μg·mL -1 carbendazim,which is 1 000 times higher than the original Chaetomium spp.The resistance was stable after 10 times transfer on non selective medium.
基金Supported by the National High-tech Research Program (2006AA10Z1B9, 2006AA100108-4-3)
文摘The leaf mould resistance gene Cf-10 on tomato confered resistant or immune to all prevalent physiological races of Cladosporium fulvum presented in three northeastern provinces of China in inoculation test. In order to better utilize Cf-10 gene in a marker-assisted selection program and to permit the pyramiding of one or several resistance genes in a cultivar, tightly linked SSR and AFLP markers were obtained by the bulked segregant analysis method. One SSR marker and three AFLP markers were identified linked to Cf-10 gene, with the distance of 9.73, 5.8, 8.5, and 10.6 cM, respectively. These markers will facilitate the selection of resistant tomato germplasm containing Cf-10 gene.
