Stem lignin content(SLC) in common wheat(Triticum aestivum L.) contributes to lodging resistance. Caffeic acid 3-O-methyltransferase(COMT) is a key enzyme involved in lignin biosynthesis. Characterization of TaCOMT ge...Stem lignin content(SLC) in common wheat(Triticum aestivum L.) contributes to lodging resistance. Caffeic acid 3-O-methyltransferase(COMT) is a key enzyme involved in lignin biosynthesis. Characterization of TaCOMT genes and development of gene-specific markers could enable marker-assisted selection in wheat breeding. In the present study, the full-length genomic DNA(gDNA) sequences of TaCOMT genes located on chromosomes 3 A, 3 B, and 3 D were cloned by homologous cloning. Two allelic variants, TaCOMT-3 Ba and TaCOMT-3 Bb, were identified and differed by a 222-bp insertion/deletion(InDel) in the 3′-untranslated region(3′-UTR). A co-dominant gene-specific marker based on this InDel was developed and designated as Ta COMT-3 BM. A total of 157 wheat cultivars and advanced lines grown in four environments were used to validate the associations between allelic patterns and SLC. The SLC of cultivars with TaCOMT-3 Ba was significantly(P<0.01) higher than that of those with TaCOMT-3 Bb, and the marker TaCOMT-3 BM could be effectively used in wheat breeding.展开更多
Thirteen fractions from the pathogenic plant fungus Setosphaeria turcica race 1 were separated and collected using high performance liquid chromatography （HPLC）. Their toxic activities were assayed through leaf punc...Thirteen fractions from the pathogenic plant fungus Setosphaeria turcica race 1 were separated and collected using high performance liquid chromatography （HPLC）. Their toxic activities were assayed through leaf puncturing on corn differentials （OH43, OH43Ht1, OH43Ht2, and OH43HtN）, and the results revealed that eight fractions were toxic and fraction 6 was specifically toxic to OH43Ht1, which could be taken as a gene-selective toxin fraction. Fraction 6 was finely purified via HPLC and condensed by freeze desiccation. Its chemical structure was analyzed with EI-MS, IR, HMBC, ^1H-NMR, and two-dimensional NMR. The results suggested that fraction 6 contained an unsaturated double bond, carbonyl and methylene groups with molecular weight of 142.展开更多
The smut Ustilago esculenta is an endophytic fungus that invades Zizania latifolia(Jiaobai)and plays an important role in inducing the host stem to form a swollen gall.The aims of this study were to investigate isolat...The smut Ustilago esculenta is an endophytic fungus that invades Zizania latifolia(Jiaobai)and plays an important role in inducing the host stem to form a swollen gall.The aims of this study were to investigate isolation,identification and inoculation methods of U.esculenta from Jiaobai.The spore suspension culturing method was the best method of isolating U.esculenta,and yeast-like fungal strains and septate hyphal strains were obtained.The universal primers ITS1 and ITS4 amplified a ribosomal DNA spacer element from all tested strains,while specific primers for Lam16A gene generated a 442 bp product only with septate hyphae strains.De novo transcriptome assembly results showed that the yeast-like fungal strains did not match Ustilago,and genomic analysis suggested the septate hyphae strains were highly similar to known smut fungi.Therefore,the septate hyphae strains were identified as U.esculenta,which indicated that the ITS primers were not species-specific but that Lam16A-specific primers can distinguish U.esculenta accurately and easily.In vitro,U.esculenta grew quickly on PDA medium at 28°C in darkness.Furthermore,an inoculation method was established to produce swollen stems by injecting a spore suspension of U.esculenta at OD600=2.5 into the basal culm internode of male Jiaobai.展开更多
China and CIMMYT have collaborated on wheat improvement for over 40 years and significant progress has been achieved in five aspects in China.A standardized protocol for testing Chinese noodle quality has been establi...China and CIMMYT have collaborated on wheat improvement for over 40 years and significant progress has been achieved in five aspects in China.A standardized protocol for testing Chinese noodle quality has been established with three selection criteria, i.e.,gluten quality, starch viscosity and flour color are identified as being responsible for noodle quality.Genomic approaches have been used to develop and validate genespecific markers, leading to the establishment of a KASP platform, and seven cultivars have been released through application of molecular marker technology.Methodology for breeding adult-plant resistance to yellow rust, leaf rust and powdery mildew, based on the pleiotropic effect of minor genes has been established, resulting in release of six cultivars.More than 330 cultivars derived from CIMMYT germplasm have been released and are now grown over 9% of the Chinese wheat production area.Additionally, physiological approaches have been used to characterize yield potential and develop high-efficiency phenotyping platforms.CIMMYT has also provided valuable training for Chinese scientists.Development of climate-resilient cultivars with application of new technology will be the priority for future collaboration.展开更多
Tomato spotted wilt virus(TSWV)is a plant pathogen that causes devastating tomato yield losses worldwide.The Sw-5b gene is one of the most effective resistance genes for TSWV control in tomato plants,and has been wide...Tomato spotted wilt virus(TSWV)is a plant pathogen that causes devastating tomato yield losses worldwide.The Sw-5b gene is one of the most effective resistance genes for TSWV control in tomato plants,and has been widely used in resistance breeding.Molecular markers are specific DNA sequences with known locations on the chromosome;they are indispensable tools in marker-assisted selection,which detects the presence of target genes to expedite breeding.We developed gene-specific molecular markers for Sw-5b to facilitate the accurate distinction of resistance(Sw-5b^(R))and susceptibility(Sw-5b^(S))alleles of Sw-5b.Using these markers,we successfully detected Sw-5b and determined its genotype(homozygous Sw-5b^(R),heterozygous Sw-5b^(R/S),or homozygous Sw-5b^(S))in six tomato varieties.Then we successfully applied these markers to 46 commercial tomato cultivars to detect and determine the genotype of Sw-5b.The results revealed a striking absence of the Sw-5b^(R)gene and high TSWV susceptibility among most of the analyzed commercial cultivars.With the assistance of the novel Sw-5b-specific molecular markers,we generated a TSWV-resistant and homozygous Sw-5b^(R)Micro-Tom tomato line,demonstrating the practical application of these markers in plant breeding.In summary,we developed novel gene-specific molecular markers for Sw-5b,and applied them to distinguish Sw-5b alleles for TSWV resistance or susceptibility.This marker set provides a valuable tool for breeding TSWV-resistant tomato varieties.展开更多
基金supported by the National Natural Science Foundation of China(31161140346 and 31461143021)the Beijing Municipal Science and Technology Project,China(D151100004415003)+1 种基金the National Key Technology R&D Program of China(2014BAD01B05)the earmarked fund for China Agriculture Research System(CARS-3-1-3)
文摘Stem lignin content(SLC) in common wheat(Triticum aestivum L.) contributes to lodging resistance. Caffeic acid 3-O-methyltransferase(COMT) is a key enzyme involved in lignin biosynthesis. Characterization of TaCOMT genes and development of gene-specific markers could enable marker-assisted selection in wheat breeding. In the present study, the full-length genomic DNA(gDNA) sequences of TaCOMT genes located on chromosomes 3 A, 3 B, and 3 D were cloned by homologous cloning. Two allelic variants, TaCOMT-3 Ba and TaCOMT-3 Bb, were identified and differed by a 222-bp insertion/deletion(InDel) in the 3′-untranslated region(3′-UTR). A co-dominant gene-specific marker based on this InDel was developed and designated as Ta COMT-3 BM. A total of 157 wheat cultivars and advanced lines grown in four environments were used to validate the associations between allelic patterns and SLC. The SLC of cultivars with TaCOMT-3 Ba was significantly(P<0.01) higher than that of those with TaCOMT-3 Bb, and the marker TaCOMT-3 BM could be effectively used in wheat breeding.
基金supported by National Excellent Teacher's Plan,Ministry of Education,China and Natural Science Foundation of Hebei Province,China(302318).
文摘Thirteen fractions from the pathogenic plant fungus Setosphaeria turcica race 1 were separated and collected using high performance liquid chromatography （HPLC）. Their toxic activities were assayed through leaf puncturing on corn differentials （OH43, OH43Ht1, OH43Ht2, and OH43HtN）, and the results revealed that eight fractions were toxic and fraction 6 was specifically toxic to OH43Ht1, which could be taken as a gene-selective toxin fraction. Fraction 6 was finely purified via HPLC and condensed by freeze desiccation. Its chemical structure was analyzed with EI-MS, IR, HMBC, ^1H-NMR, and two-dimensional NMR. The results suggested that fraction 6 contained an unsaturated double bond, carbonyl and methylene groups with molecular weight of 142.
基金This study was financially supported by the 58th batch of the China Postdoctoral Science Foundation,Jiangsu Agricul-ture Science and Technology Innovation Fund(CX(20)3104)Natural Science Fund Project of Colleges in Jiangsu Province(15KJB210006).
文摘The smut Ustilago esculenta is an endophytic fungus that invades Zizania latifolia(Jiaobai)and plays an important role in inducing the host stem to form a swollen gall.The aims of this study were to investigate isolation,identification and inoculation methods of U.esculenta from Jiaobai.The spore suspension culturing method was the best method of isolating U.esculenta,and yeast-like fungal strains and septate hyphal strains were obtained.The universal primers ITS1 and ITS4 amplified a ribosomal DNA spacer element from all tested strains,while specific primers for Lam16A gene generated a 442 bp product only with septate hyphae strains.De novo transcriptome assembly results showed that the yeast-like fungal strains did not match Ustilago,and genomic analysis suggested the septate hyphae strains were highly similar to known smut fungi.Therefore,the septate hyphae strains were identified as U.esculenta,which indicated that the ITS primers were not species-specific but that Lam16A-specific primers can distinguish U.esculenta accurately and easily.In vitro,U.esculenta grew quickly on PDA medium at 28°C in darkness.Furthermore,an inoculation method was established to produce swollen stems by injecting a spore suspension of U.esculenta at OD600=2.5 into the basal culm internode of male Jiaobai.
基金funded by the National Natural Science Foundation of China (31461143021, 31761143006)
文摘China and CIMMYT have collaborated on wheat improvement for over 40 years and significant progress has been achieved in five aspects in China.A standardized protocol for testing Chinese noodle quality has been established with three selection criteria, i.e.,gluten quality, starch viscosity and flour color are identified as being responsible for noodle quality.Genomic approaches have been used to develop and validate genespecific markers, leading to the establishment of a KASP platform, and seven cultivars have been released through application of molecular marker technology.Methodology for breeding adult-plant resistance to yellow rust, leaf rust and powdery mildew, based on the pleiotropic effect of minor genes has been established, resulting in release of six cultivars.More than 330 cultivars derived from CIMMYT germplasm have been released and are now grown over 9% of the Chinese wheat production area.Additionally, physiological approaches have been used to characterize yield potential and develop high-efficiency phenotyping platforms.CIMMYT has also provided valuable training for Chinese scientists.Development of climate-resilient cultivars with application of new technology will be the priority for future collaboration.
基金supported by National Key R&D Program of China(2022YFD1401200,2022YFF1001500)the National Natural Science Foundation of China(31972241)+2 种基金the Jiangsu Key Technology R&D Program and International Science and Technology Cooperation Project(BZ2023030)Key Science and Technology Program of Hainan Province(ZDKJ2021007)Yunnan Seed Laboratory(202205AR070001).
文摘Tomato spotted wilt virus(TSWV)is a plant pathogen that causes devastating tomato yield losses worldwide.The Sw-5b gene is one of the most effective resistance genes for TSWV control in tomato plants,and has been widely used in resistance breeding.Molecular markers are specific DNA sequences with known locations on the chromosome;they are indispensable tools in marker-assisted selection,which detects the presence of target genes to expedite breeding.We developed gene-specific molecular markers for Sw-5b to facilitate the accurate distinction of resistance(Sw-5b^(R))and susceptibility(Sw-5b^(S))alleles of Sw-5b.Using these markers,we successfully detected Sw-5b and determined its genotype(homozygous Sw-5b^(R),heterozygous Sw-5b^(R/S),or homozygous Sw-5b^(S))in six tomato varieties.Then we successfully applied these markers to 46 commercial tomato cultivars to detect and determine the genotype of Sw-5b.The results revealed a striking absence of the Sw-5b^(R)gene and high TSWV susceptibility among most of the analyzed commercial cultivars.With the assistance of the novel Sw-5b-specific molecular markers,we generated a TSWV-resistant and homozygous Sw-5b^(R)Micro-Tom tomato line,demonstrating the practical application of these markers in plant breeding.In summary,we developed novel gene-specific molecular markers for Sw-5b,and applied them to distinguish Sw-5b alleles for TSWV resistance or susceptibility.This marker set provides a valuable tool for breeding TSWV-resistant tomato varieties.
