Low temperature is the most common abiotic stress factors during the eggplant cultivation in solar greenhouses.Melatonin plays important roles in plant resistance to low temperature.However,the role of melatonin in re...Low temperature is the most common abiotic stress factors during the eggplant cultivation in solar greenhouses.Melatonin plays important roles in plant resistance to low temperature.However,the role of melatonin in regulating chilling tolerance and extending the preharvest shelf life of eggplant fruits is still unknown.In this study,we investigated the effects of exogenous melatonin on eggplant plants and fruits in response to low temperature.Under simulated low-temperature conditions,exogenous melatonin significantly relieved the chilling symptoms of seedlings by reducing reactive oxygen species (ROS) and malondialdehyde (MDA) levels and relative leakage rates.These reductions were caused by higher superoxide dismutase (SOD) and catalase (CAT) activities and increased endogenous polyamine and melatonin levels compared with those in untreated seedlings.Notably,the expression levels of SOD,CAT1/2,and polyamine synthesis genes (ADC and ODC) were also increased by 100μmol·L~(-1)melatonin,as well as those of genes involved in melatonin synthesis (TDC,T5H,SNAT,ASMT,and COMT) and cold regulation (COR1,CBFa/b,and ZAT2/6/12).To further investigate the effects of melatonin on eggplant leaves and fruits under natural low temperature conditions,100μmol·L~(-1)melatonin was sprayed on the functional leaves at three days before commodity maturation.Melatonin significantly alleviated chilling injury in the leaves and pericarp and extended the preharvest shelf life of the fruit by increasing the expression of COR1,CBF,ZAT2/6/12,and API5 and decreasing the expression of senescence-related genes (NCED1/2 and SAG12).Therefore,100μmol·L~(-1)melatonin improved chilling tolerance and fruit shelf life by upregulating ZAT2/6/12 to affect ROS-and senescence-related processes,which provides a reference for alleviating cold stress and extending the preharvest fruit shelf life in eggplant.展开更多
The naturally occurring mutant eggplant line 05ms was identified with reverse thermosensitive genic male sterility(rTGMS),but its temperature-responsive fertility mechanisms remain largely unknown.Here,we studied the ...The naturally occurring mutant eggplant line 05ms was identified with reverse thermosensitive genic male sterility(rTGMS),but its temperature-responsive fertility mechanisms remain largely unknown.Here,we studied the flower morphology,anther cellular structure,and genome-wide gene expression of this rTGMS line.Candidate genes for thermosensitive male sterility during the microspore development of 05ms and the temperature-insensitive line S63 under low-temperature(LT)and high-temperature(HT)conditions were identified.Under LT,tapetum cells were vacuolated and had delayed disintegration in 05ms.RNA-seq analysis indicated that DEGs were enriched in the KEGG pathways‘plant hormone signal transduction’,‘starch and sucrose metabolism’,and‘phenylpropanoid biosynthesis’.We identified two genes,4CLL1(Sme2.5_00368.1_g00010.1)and CKI1(Sme2.5_10056.1_g00002.1),which could potentially regulate eggplant anther development and may be candidate genes for rTGMS.Finally,we propose a working model of anther abortion for rTGMS in eggplant.CKI1 responds to LT stress and causes expression changes in genes related to anther development,such as 4CLL1,and the cellular structure of the tapetum becomes abnormal,causing male sterility.The findings of this study explain the underlying molecular mechanisms of male sterility in eggplant rTGMS lines.展开更多
Flowering time is an important agronomic trait of Chinese cabbage with late flowering being a primary breeding objective.In our previous work,we obtained Chinese cabbage-cabbage translocation lines that contained seve...Flowering time is an important agronomic trait of Chinese cabbage with late flowering being a primary breeding objective.In our previous work,we obtained Chinese cabbage-cabbage translocation lines that contained several beneficial cabbage genes.Cabbage-specific molecular markers show that these genes were coming from chromosome C01 of cabbage.In this study,we investigated the inheritance of flowering time in a couple of translocation lines and analyzed the transmission rate of molecular markers in the offspring.Consequently,we obtained the late flowering Chinese cabbage-cabbage translocation line‘AT7–4’in which the flowering time was later than that of‘85–1’by about 7 days under 4-week vernalization.Based on previous studies of the genomes of Chinese cabbage and cabbage,we located the cabbage-specific molecular markers that were closely linked at the top of the chromosome A01 in the F2mapping population generated by self-crossing F1s derived from a cross between the translocation line‘AT7–4’and Chinese cabbage‘14–36’.Five flowering-related genes in the alien fragment were found by functional annotation and their molecular markers were developed.This study lays the foundation for the future improvement of Chinese cabbage varieties using A-C translocation lines.展开更多
Fleshy fruit shape is an important external quality trait influencing the usage of fruits and consumer preference.Thus,modification of fruit shape has become one of the major objectives for crop improvement.However,th...Fleshy fruit shape is an important external quality trait influencing the usage of fruits and consumer preference.Thus,modification of fruit shape has become one of the major objectives for crop improvement.However,the underlying mechanisms of fruit shape regulation are poorly understood.In this review we summarize recent progress in the genetic basis of fleshy fruit shape regulation using tomato,cucumber,and peach as examples.Comparative analyses suggest that the OFP-TRM(OVATE Family Protein-TONNEAU1 Recruiting Motif)and IQD(IQ67 domain)pathways are probably conserved in regulating fruit shape by primarily modulating cell division patterns across fleshy fruit species.Interestingly,cucumber homologs of FRUITFULL(FUL1),CRABS CLAW(CRC)and 1-aminocyclopropane-1-carboxylate synthase 2(ACS2)were found to regulate fruit elongation.We also outline the recent progress in fruit shape regulation mediated by OFP-TRM and IQD pathways in Arabidopsis and rice,and propose that the OFP-TRM pathway and IQD pathway coordinate regulate fruit shape through integration of phytohormones,including brassinosteroids,gibberellic acids,and auxin,and microtubule organization.In addition,functional redundancy and divergence of the members of each of the OFP,TRM,and IQD families are also shown.This review provides a general overview of current knowledge in fruit shape regulation and discusses the possible mechanisms that need to be addressed in future studies.展开更多
The genus Brassica contains a rich diversity of species and morphological types,including leaf,root,and oil crops,all of which show substantial phenotypic variation.Both Chinese cabbage and cabbage are typical leaf-ty...The genus Brassica contains a rich diversity of species and morphological types,including leaf,root,and oil crops,all of which show substantial phenotypic variation.Both Chinese cabbage and cabbage are typical leaf-type crops with normal roots.We created translocation lines based on interspecific crosses between Chinese cabbage and cabbage and identified qdh225,which exhibited a swollen-root phenotype.The swollen root of qdh225 contained a large number of granular substances,and the formation of its irregular morphological tissue was caused by a thickening of the phloem.Transcriptomic and metabolomic data suggested that differential expression of genes encoding nine types of enzymes involved in starch and sucrose metabolism caused changes in starch synthesis and degradation in the swollen root.These genes jointly regulated sucrose and starch levels,leading to significant enrichment of starch and soluble proteins in the swollen root and a reduction in the content of soluble sugars such as d-glucose and trehalose 6-phosphate.A significant increase in auxin(IAA)and abscisic acid(ABA)contents and a decrease in gibberellin(GA)content in the swollen root likely promoted the differential expression of genes associated with hormone signal transduction,thereby regulating the development of the swollen root.Taken together,our data suggest that accumulation of IAA and ABA and reduction in GA promote swollen root formation by regulating hormone-mediated signaling,leading to a thickening of phloem,root enlargement,and substantial accumulation of starch and soluble proteins.The latter provide materials,energy,and nutrient sources for the development of swollen roots.展开更多
The agricultural and consumer quality of Chinese cabbage is determined by its shape.The shape is defined by the folding of the heading leaves,which defines the head top shape(HTS).The overlapping HTS,in which the head...The agricultural and consumer quality of Chinese cabbage is determined by its shape.The shape is defined by the folding of the heading leaves,which defines the head top shape(HTS).The overlapping HTS,in which the heading leaves curve inward and overlap at the top,is the shape preferred by consumers.To understand the genetic regulation of HTS,we generated a large segregating F 2 population from a cross between pak choi and Chinese cabbage,with phenotypes ranging from nonheading to heading with either outward curving or inward curving overlapping heading leaves.HTS was correlated with plant height,outer/rosette leaf length,and petiole length.A high-density genetic map was constructed.Quantitative trait locus(QTL)analysis resulted in the identification of 22 QTLs for leafy head-related traits,which included five HTS QTLs.Bulked segregant analysis(BSA)was used to confirm HTS QTLs and identify candidate genes based on informative single-nucleotide polymorphisms.Interestingly,the HTS QTLs colocalized with QTLs for plant height,outer/rosette leaf,and petiole length,consistent with the observed phenotypic correlations.Combined QTL analysis and BSA laid a foundation for molecular marker-assisted breeding of Chinese cabbage HTS and directions for further research on the genetic regulation of this trait.展开更多
With the complementation of whole-genome sequencing of Chinese cabbage,it is necessary to develop genome-wide Simple Sequence Repeat(SSR)markers and analyse their characteristics,which will bring a revolution in the m...With the complementation of whole-genome sequencing of Chinese cabbage,it is necessary to develop genome-wide Simple Sequence Repeat(SSR)markers and analyse their characteristics,which will bring a revolution in the molecular marker-assisted breeding of Chinese cabbage.In this study distribution and characteristics of SSR loci in the genome of Chinese cabbage'Chiifu'was analyzed.Finally,a total of 173,892 SSR markers that occurred in 10 chromosomes were identified,and Perfect Repeat Motifs(P type)which is a main form of SSR loci with a mean distance of 1.89 kb/SSR was identified.Among them,mono-,di-,and tri-nucleotide repeat motifs were equally distributed across chromosomes compared with tetra-,penta-,and hexa-nucleotide repeat motifs.The largest proportion of SSR loci consisted of mono-and dinucleotide repeat motifs,which accounted for 93.04%of the total SSR loci.A/T and AT/TA were the most abundant motifs,accounting for 97.61%and 64.05%of the mono-and dinucleotide repeats,respectively.Furthermore,200 SSR markers were used for the amplification of 12 Chinese cabbage germplasm,in which 30 were highly polymorphic.These SSR markers were further used for the association analyses of flowering time of 190 Chinese cabbage accessions.The results revealed that 9 and 10 alleles were associated with bolting and flowering time,respectivley.The results show that development of SSR markers is feasible and useful in marker assisted selection of Chinese cabbage.展开更多
Chinese cabbage(Brassica rapa ssp.pekinensis)is an economically important vegetable crop throughout the world,especially in Asia.High-quality genome sequences are available for Chinese cabbage,but gene functional stud...Chinese cabbage(Brassica rapa ssp.pekinensis)is an economically important vegetable crop throughout the world,especially in Asia.High-quality genome sequences are available for Chinese cabbage,but gene functional studies remain challenging.To promote functional genomic studies of Chinese cabbage,we generated an ethyl methane sulfonate(EMS)mutant population of~8000 M_(2) plants using the double haploid inbred line A03 as the parent.The genome of A03 was sequenced and used as a reference for high-throughput functional characterization of gene mutations at the whole-genome level.A total of 300 M_(2) to M_(5) EMS mutants were phenotypically screened and then sequenced,revealing 750629 SNPs and 46272 InDel mutations that cover 98.27%of all predicted genes in the A03 genome.A forward-genetics approach was successfully used to identify two genes with chloroplast-related functions that are responsible for the yellow leaf mutant trait.A reverse-genetics approach was also used to identify associations between mutations in five genes of the glucosinolate biosynthetic pathway and variations in glucosinolate content of the mutant plants.In addition,we built the Chinese cabbage EMS mutation database(CCEMD,www.bioinformaticslab.cn/EMSmutation/home)to increase the usability of this mutant population resource.In summary,we performed large-scale screening of a heading Chinese cabbage EMS mutant collection at the phenotypic and genotypic levels,which will facilitate gene mining of Chinese cabbage and might also be useful for the study of other Brassica crops.展开更多
基金Introduction of Talents for Scientific Research of State Key Laboratory of North China Crop Improvement and Regulation (Grant No.NCCIR2020RC-11)Hebei Fruit Vegetables Seed Industry Science and Technology Innovation Team Project (Grant No.21326309D)+2 种基金Vegetable Innovation Team Project of Hebei Modern Agricultural Industrial Technology System (Grant No.HBCT2018030203)Introduction of Talents for Scientific Research of Hebei Agriculture University (Grant No.YJ2020048)Basic Scientific Research Funds of Provincial Universities of Hebei Province (Grant No.KY2021056) for the provision of funds。
文摘Low temperature is the most common abiotic stress factors during the eggplant cultivation in solar greenhouses.Melatonin plays important roles in plant resistance to low temperature.However,the role of melatonin in regulating chilling tolerance and extending the preharvest shelf life of eggplant fruits is still unknown.In this study,we investigated the effects of exogenous melatonin on eggplant plants and fruits in response to low temperature.Under simulated low-temperature conditions,exogenous melatonin significantly relieved the chilling symptoms of seedlings by reducing reactive oxygen species (ROS) and malondialdehyde (MDA) levels and relative leakage rates.These reductions were caused by higher superoxide dismutase (SOD) and catalase (CAT) activities and increased endogenous polyamine and melatonin levels compared with those in untreated seedlings.Notably,the expression levels of SOD,CAT1/2,and polyamine synthesis genes (ADC and ODC) were also increased by 100μmol·L~(-1)melatonin,as well as those of genes involved in melatonin synthesis (TDC,T5H,SNAT,ASMT,and COMT) and cold regulation (COR1,CBFa/b,and ZAT2/6/12).To further investigate the effects of melatonin on eggplant leaves and fruits under natural low temperature conditions,100μmol·L~(-1)melatonin was sprayed on the functional leaves at three days before commodity maturation.Melatonin significantly alleviated chilling injury in the leaves and pericarp and extended the preharvest shelf life of the fruit by increasing the expression of COR1,CBF,ZAT2/6/12,and API5 and decreasing the expression of senescence-related genes (NCED1/2 and SAG12).Therefore,100μmol·L~(-1)melatonin improved chilling tolerance and fruit shelf life by upregulating ZAT2/6/12 to affect ROS-and senescence-related processes,which provides a reference for alleviating cold stress and extending the preharvest fruit shelf life in eggplant.
基金financed by the Hebei Natural Science Foundation(C2015301055)Hebei Science and Technology Plan Project(16226308D)+1 种基金National Bulk Vegetable Industry Technology System Project(CARS-23-G-05)Hebei Vegetable Industry Technology System(HBCT2018030203).
文摘The naturally occurring mutant eggplant line 05ms was identified with reverse thermosensitive genic male sterility(rTGMS),but its temperature-responsive fertility mechanisms remain largely unknown.Here,we studied the flower morphology,anther cellular structure,and genome-wide gene expression of this rTGMS line.Candidate genes for thermosensitive male sterility during the microspore development of 05ms and the temperature-insensitive line S63 under low-temperature(LT)and high-temperature(HT)conditions were identified.Under LT,tapetum cells were vacuolated and had delayed disintegration in 05ms.RNA-seq analysis indicated that DEGs were enriched in the KEGG pathways‘plant hormone signal transduction’,‘starch and sucrose metabolism’,and‘phenylpropanoid biosynthesis’.We identified two genes,4CLL1(Sme2.5_00368.1_g00010.1)and CKI1(Sme2.5_10056.1_g00002.1),which could potentially regulate eggplant anther development and may be candidate genes for rTGMS.Finally,we propose a working model of anther abortion for rTGMS in eggplant.CKI1 responds to LT stress and causes expression changes in genes related to anther development,such as 4CLL1,and the cellular structure of the tapetum becomes abnormal,causing male sterility.The findings of this study explain the underlying molecular mechanisms of male sterility in eggplant rTGMS lines.
基金supported by the State Key Program of National Natural Science Foundation of China(Grant Nos.31930098,31772324)Hebei Provincial Natural Science Fund for Distinguished Young(Grant No.C2020204063)+6 种基金Natural Science Foundation and basic research project in Hebei Province(Grant No.18966925D)the Innovative Research Group Project of Hebei Natural Science Foundation(Grant No.C2020204111)the Agricultural Science and Technology Innovation Program of CAAS(Grant No.CAASXTCX2019025)the National Natural Science Foundation of China(Grant No.31672151)the Science and Technology Support Program of Hebei(Grant No.16226304D-2)Science and Technology Research Project of Universities in Hebei Province(BJ2019020)the International Science and Technology Cooperation base Special Project of Hebei(Grant No.20592901D)。
文摘Flowering time is an important agronomic trait of Chinese cabbage with late flowering being a primary breeding objective.In our previous work,we obtained Chinese cabbage-cabbage translocation lines that contained several beneficial cabbage genes.Cabbage-specific molecular markers show that these genes were coming from chromosome C01 of cabbage.In this study,we investigated the inheritance of flowering time in a couple of translocation lines and analyzed the transmission rate of molecular markers in the offspring.Consequently,we obtained the late flowering Chinese cabbage-cabbage translocation line‘AT7–4’in which the flowering time was later than that of‘85–1’by about 7 days under 4-week vernalization.Based on previous studies of the genomes of Chinese cabbage and cabbage,we located the cabbage-specific molecular markers that were closely linked at the top of the chromosome A01 in the F2mapping population generated by self-crossing F1s derived from a cross between the translocation line‘AT7–4’and Chinese cabbage‘14–36’.Five flowering-related genes in the alien fragment were found by functional annotation and their molecular markers were developed.This study lays the foundation for the future improvement of Chinese cabbage varieties using A-C translocation lines.
基金This work was supported by the Natural Science Foundation of Hebei Province(C2021204015)the 2021 Project for the Introduction of Oversea Students in Hebei Province(C20210510)+4 种基金science and technology research projects of colleges and universities in Hebei Province(ZD2022111)the Introduction of Talents Start-up fund of the State Key Laboratory of North China Crop Improvement and Regulation(NCCIR2020RC-13)the Introduction of Talents Start-up fund of Hebei Agricultural University(YJ2020067)the Hebei Fruit Vegetables Seed Industry Science and Technology Innovation Team Project(21326309D)the Vegetable Innovation Team Project of Hebei Modern Agricultural Industrial Technology System(HBCT2018030203).
文摘Fleshy fruit shape is an important external quality trait influencing the usage of fruits and consumer preference.Thus,modification of fruit shape has become one of the major objectives for crop improvement.However,the underlying mechanisms of fruit shape regulation are poorly understood.In this review we summarize recent progress in the genetic basis of fleshy fruit shape regulation using tomato,cucumber,and peach as examples.Comparative analyses suggest that the OFP-TRM(OVATE Family Protein-TONNEAU1 Recruiting Motif)and IQD(IQ67 domain)pathways are probably conserved in regulating fruit shape by primarily modulating cell division patterns across fleshy fruit species.Interestingly,cucumber homologs of FRUITFULL(FUL1),CRABS CLAW(CRC)and 1-aminocyclopropane-1-carboxylate synthase 2(ACS2)were found to regulate fruit elongation.We also outline the recent progress in fruit shape regulation mediated by OFP-TRM and IQD pathways in Arabidopsis and rice,and propose that the OFP-TRM pathway and IQD pathway coordinate regulate fruit shape through integration of phytohormones,including brassinosteroids,gibberellic acids,and auxin,and microtubule organization.In addition,functional redundancy and divergence of the members of each of the OFP,TRM,and IQD families are also shown.This review provides a general overview of current knowledge in fruit shape regulation and discusses the possible mechanisms that need to be addressed in future studies.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.31930098 and 32172560)the Hebei Provincial Natural Science Fund for Distinguished Young Scholars(Grant No.C2020204063)the Innovative Research Group Project of Hebei Natural Science Foundation(Grant No.C2020204111).
文摘The genus Brassica contains a rich diversity of species and morphological types,including leaf,root,and oil crops,all of which show substantial phenotypic variation.Both Chinese cabbage and cabbage are typical leaf-type crops with normal roots.We created translocation lines based on interspecific crosses between Chinese cabbage and cabbage and identified qdh225,which exhibited a swollen-root phenotype.The swollen root of qdh225 contained a large number of granular substances,and the formation of its irregular morphological tissue was caused by a thickening of the phloem.Transcriptomic and metabolomic data suggested that differential expression of genes encoding nine types of enzymes involved in starch and sucrose metabolism caused changes in starch synthesis and degradation in the swollen root.These genes jointly regulated sucrose and starch levels,leading to significant enrichment of starch and soluble proteins in the swollen root and a reduction in the content of soluble sugars such as d-glucose and trehalose 6-phosphate.A significant increase in auxin(IAA)and abscisic acid(ABA)contents and a decrease in gibberellin(GA)content in the swollen root likely promoted the differential expression of genes associated with hormone signal transduction,thereby regulating the development of the swollen root.Taken together,our data suggest that accumulation of IAA and ABA and reduction in GA promote swollen root formation by regulating hormone-mediated signaling,leading to a thickening of phloem,root enlargement,and substantial accumulation of starch and soluble proteins.The latter provide materials,energy,and nutrient sources for the development of swollen roots.
基金the National Natural Science Foundation of China(Grant Nos.32002054,31930098,and 31801857)he National Key R&D of China(Grant No.2016YFD0100204-17)+2 种基金the Science and Technology Support Program of Hebei(Grant No.360108)the Natural Science Foundation of Hebei(Grant No.C2020204122)the International Cooperation Project in the Science and Technology Support Program of Hebei(Grant Nos.2019YX023A and 17396315D)。
文摘The agricultural and consumer quality of Chinese cabbage is determined by its shape.The shape is defined by the folding of the heading leaves,which defines the head top shape(HTS).The overlapping HTS,in which the heading leaves curve inward and overlap at the top,is the shape preferred by consumers.To understand the genetic regulation of HTS,we generated a large segregating F 2 population from a cross between pak choi and Chinese cabbage,with phenotypes ranging from nonheading to heading with either outward curving or inward curving overlapping heading leaves.HTS was correlated with plant height,outer/rosette leaf length,and petiole length.A high-density genetic map was constructed.Quantitative trait locus(QTL)analysis resulted in the identification of 22 QTLs for leafy head-related traits,which included five HTS QTLs.Bulked segregant analysis(BSA)was used to confirm HTS QTLs and identify candidate genes based on informative single-nucleotide polymorphisms.Interestingly,the HTS QTLs colocalized with QTLs for plant height,outer/rosette leaf,and petiole length,consistent with the observed phenotypic correlations.Combined QTL analysis and BSA laid a foundation for molecular marker-assisted breeding of Chinese cabbage HTS and directions for further research on the genetic regulation of this trait.
基金supported by the fundings from the National Natural Science Foundation of China (31930098,32172594)Hebei Provincial Department of Human Resources and Social Security (C20210363)+1 种基金Hebei Provincial Department of Science and Technology (216Z2904G)the Natural Science Foundation of Heibei (C2020204111).
文摘With the complementation of whole-genome sequencing of Chinese cabbage,it is necessary to develop genome-wide Simple Sequence Repeat(SSR)markers and analyse their characteristics,which will bring a revolution in the molecular marker-assisted breeding of Chinese cabbage.In this study distribution and characteristics of SSR loci in the genome of Chinese cabbage'Chiifu'was analyzed.Finally,a total of 173,892 SSR markers that occurred in 10 chromosomes were identified,and Perfect Repeat Motifs(P type)which is a main form of SSR loci with a mean distance of 1.89 kb/SSR was identified.Among them,mono-,di-,and tri-nucleotide repeat motifs were equally distributed across chromosomes compared with tetra-,penta-,and hexa-nucleotide repeat motifs.The largest proportion of SSR loci consisted of mono-and dinucleotide repeat motifs,which accounted for 93.04%of the total SSR loci.A/T and AT/TA were the most abundant motifs,accounting for 97.61%and 64.05%of the mono-and dinucleotide repeats,respectively.Furthermore,200 SSR markers were used for the amplification of 12 Chinese cabbage germplasm,in which 30 were highly polymorphic.These SSR markers were further used for the association analyses of flowering time of 190 Chinese cabbage accessions.The results revealed that 9 and 10 alleles were associated with bolting and flowering time,respectivley.The results show that development of SSR markers is feasible and useful in marker assisted selection of Chinese cabbage.
基金supported by the Innovative Research Group Project of Hebei Natural Science Foundation(grant no.C2020204111)the National Natural Science Foundation of China(grant nos.32002054,31902005,31930098,31972411,31722048,31872947)+7 种基金the International Science and Technology Cooperation base Special Project of Hebei(grant no.20592901D)Key R&D Project of Hebei(grant no.21326344D)the Natural Science Foundation of Hebei(grant nos.C2020204122,C2021204163)the Introducing Foreign Intellectual Project of Hebei(grant no.2019YX023A)the Post doctoral Science Foundation of China(grant no.2020M680901)the Science and Technology Research Project of University in Hebei(grant no.BJ2019020)the Post-graduate's Innovation Fund Project of Hebei(grant no.CXZZBS2017069)the State Key Laboratory of North China Crop Improvement and Regulation(NCCIR20202KF-2).
文摘Chinese cabbage(Brassica rapa ssp.pekinensis)is an economically important vegetable crop throughout the world,especially in Asia.High-quality genome sequences are available for Chinese cabbage,but gene functional studies remain challenging.To promote functional genomic studies of Chinese cabbage,we generated an ethyl methane sulfonate(EMS)mutant population of~8000 M_(2) plants using the double haploid inbred line A03 as the parent.The genome of A03 was sequenced and used as a reference for high-throughput functional characterization of gene mutations at the whole-genome level.A total of 300 M_(2) to M_(5) EMS mutants were phenotypically screened and then sequenced,revealing 750629 SNPs and 46272 InDel mutations that cover 98.27%of all predicted genes in the A03 genome.A forward-genetics approach was successfully used to identify two genes with chloroplast-related functions that are responsible for the yellow leaf mutant trait.A reverse-genetics approach was also used to identify associations between mutations in five genes of the glucosinolate biosynthetic pathway and variations in glucosinolate content of the mutant plants.In addition,we built the Chinese cabbage EMS mutation database(CCEMD,www.bioinformaticslab.cn/EMSmutation/home)to increase the usability of this mutant population resource.In summary,we performed large-scale screening of a heading Chinese cabbage EMS mutant collection at the phenotypic and genotypic levels,which will facilitate gene mining of Chinese cabbage and might also be useful for the study of other Brassica crops.