Photoperiod and temperature are crucial factors that trigger flowering in Brassica juncea(B.juncea).However,the underlying regulatory mechanisms remain poorly understood.The MADS-box transcription factor AGL18 acts as...Photoperiod and temperature are crucial factors that trigger flowering in Brassica juncea(B.juncea).However,the underlying regulatory mechanisms remain poorly understood.The MADS-box transcription factor AGL18 acts as a pivotal repressor of floral transition and functions redundantly with AGL15.In this study,we isolated BjuAGL18-1 from B.juncea and identified two unique transcripts,resulting in two distinct proteins:a full-length protein,BjuAGL18-1L,and a truncated protein,BjuAGL18-1S.Further investigation showed that the two isoforms had similar subcellular localizations but different expression patterns in various plant tissues.Notably,BjuAGL18-1L and BjuAGL18-1S were abundantly induced under short-and long-day photoperiods,respectively.BjuAGL18-1L overexpression in B.juncea and Arabidopsis thaliana(A.thaliana)led to late flowering,whereas BjuAGL18-1S overexpression resulted in early flowering.Yeast two-hybrid,bimolecular fluorescent complementation,and luciferase complementation assays showed that BjuAGL18-1L,but not BjuAGL18-1S(which lacked the EAR motif),interacted with the co-repressor BjuAFR2 and the histone deacetylase BjuHDA9 to form a multiprotein complex.Further analysis indicated that BjuAGL18-1L could also form a complex with BjuAGL15 and bind to the BjuFUL promoter,thus inhibiting its expression.However,BjuAGL18-1S interacted with BjuAGL18-1L to form heterodimers,which attenuated their activities,likely by disrupting their binding to target genes,resulting in accelerated flowering progression.These results suggest that BjuAGL18-1 is involved in photoperiod-induced flowering via different regulatory mechanisms in B.juncea.展开更多
The potherb mustard Xuecai(XC)cultivar is a cruciferous vegetable that is popular either fresh or pickled.Due to the deep notches in the edges of leaves in mustard XC,this plant can be said to have multipinnately lobe...The potherb mustard Xuecai(XC)cultivar is a cruciferous vegetable that is popular either fresh or pickled.Due to the deep notches in the edges of leaves in mustard XC,this plant can be said to have multipinnately lobed leaves.The net photosynthesis of lobed leaves is significantly greater than that of simple leaves.However,the molecular mechanism of leaf shape variation has not been determined.Here,we used HiFi and Hi-C data to assemble the XC genome.The genome was 961.72 Mb in size,with a contig N50 value of 6.565 Mb.The XC genome was compared with four previously sequenced mustard genomes,and the genomic collinearity regions,SNPs,and indels were identified.Five BjRCO genes were found on chromosome(Chr.)A10 in potherb mustard XC when the BjRCO gene locus was compared against other sequenced B.juncea genomes.Segmental duplication was found to contribute to the BjRCO gene copy number.The transcript expression of BjRCO genes was greater in multipinnately lobed leaves than in sawtooth-like leaves.Together,these findings indicate that both the greater copy number and the expression level of BjRCO genes regulate leaf shape from simple to complex in B.juncea.Gene editing of the BjRCO gene from XC changed the leaf shape from multipinnately lobed to simple.The high-quality XC genome sequence not only provides new insight into B.juncea leaf-type genomics but also helps in deciphering leaf shape variation.Our study provides insights into the variation and evolution of important traits in Brassica plants through a comparative analysis of the sequenced genomes.展开更多
Elucidating crops'physiological and molecular mechanisms to adapt to low nitrogen environment and promoting nitrogen transfer from senescent leaves to new leaves is crucial in improving Brassica's nitrogen use...Elucidating crops'physiological and molecular mechanisms to adapt to low nitrogen environment and promoting nitrogen transfer from senescent leaves to new leaves is crucial in improving Brassica's nitrogen use efficiency(NUE).Glutamine synthetase gene(GS)plays a vital role in helping plants reassimilate ammonium released from protein degradation in leaves,and it was the focus of our research on this topic.In this study,we identified high(H141)and low(L65)NUE genotypes of Brassica juncea with different responses to low-nitrogen stress.We found that H141 has a lower nitrate content but higher ammonium and free amino acid contents as well as higher nitrate reductase and GS activities in the shoots.These physiological indicators are responsible for the high NUE of H141.Wholegenome resequencing data revealed that 5,880 genes associated with NUE are polymorphic between H141 and L65.These genes participate in various amino acid,carbohydrate,and energy metabolic pathways.Haplotype analysis revealed two haplotypes for BjuB05.GS1.4,Hap1 and Hap2,which have multiple single nucleotide polymorphisms or insertions/deletions in the regulatory regions of the 5′and 3′untranslated regions and introns.Furthermore,the shoot NUE of Hap1 is significantly lower than that of Hap2.These two haplotypes of BjuB05.GS1.4 lead to differences in the shoot NUEs of different genetic populations of mustard and are associated with the local soil nitrogen content,suggesting that they might help mustard to adapt to different geographic localities.In conclusion,the results of our study shed light on the physiological and molecular mechanisms underlying different mustard NUE genotypes and demonstrate the enormous potential of NUE breeding in B.juncea.展开更多
Rapeseed mustard(Brassica juncea L.) is the third most important oilseed crop in the world, but the geneticmechanism underlying its massive phenotypic variation remains largely unexplored. In this study, specific leng...Rapeseed mustard(Brassica juncea L.) is the third most important oilseed crop in the world, but the geneticmechanism underlying its massive phenotypic variation remains largely unexplored. In this study, specific length amplified fragment sequencing(SLAF-Seq) was used to resequence a population comprising 197 F8recombinantinbred lines(RILs) derived from a cross between vegetable-type Qichi881 and oilseed-type YufengZC of B. juncea. In total, 438,895 high-quality SLAFs were discovered, 47,644 of which were polymorphic, and 3,887 of the polymorphic markers met the requirements for genetic map construction. The final map included 3,887 markers on 18 linkage groups and was 1,830.23 centiMorgan(cM) in length, with an average distance of 0.47 cM between adjacent markers. Using the newly constructed high-density genetic map, a total of 53 QTLs for erucicacid(EA), oleic acid(OA), and linolenic acid(LNA) were detected and integrated into eight consensus QTLswith two for each of these traits. For each of these three traits, two candidate genes were cloned and sequence analysis indicated colocalization with their respective consensus QTLs. The co-dominant allele-specific markers for Bju.FAD3.A03 and Bju.FAD3.B07 were developed and showed co-localization with their consensus QTLs andco-segregation with LNA content, further supporting the results of QTL mapping and bioinformatic analysis. Theexpression levels of the cloned homologous genes were also determined, and the genes were tightly correlatedwith the EA, OA and LNA contents of different lines. The results of this study will facilitate the improvement offatty acid traits and molecular breeding of B. juncea. Further uses of the high-density genetic map created in this study are also discussed.展开更多
In this study, Bacil us amyloliquefaciens A3 was continual y incubated in shake fIasks contalning wastewater from sweet potato starch production as an ef-fective biofertiIizer for cuItivation of Brassica juncea var. m...In this study, Bacil us amyloliquefaciens A3 was continual y incubated in shake fIasks contalning wastewater from sweet potato starch production as an ef-fective biofertiIizer for cuItivation of Brassica juncea var. multiceps（XueIihong）. Based on pot experiments in the greenhouse, the effects of chemical fertiIizers （CN）, biofertiIizer （BF）, inactivated broth （BI）, starch wastewater （SW） and the combination of biofertiIizer and chemical fertiIizer （BC） on the yield, NO3- content and NO2- con-tent of XueIihong, soiI physicochemical properties and N2O emission were investi-gated. The resuIts showed that the yield of XueIihong in BC and CN treatments was improved by five times compared with CK; BF and SW treatments had insignifi-cant impact on the yield of XueIihong. Compared with CN treatment, BCL treatment exhibited simiIar improving effects on the yield of XueIihong, in which NO3- content of XueIihong and soiI was reduced by 16.4%-73.6% and 22%-29%, which reduced the risk of nitrogen eIuviations in soiI; average N2O fIux （FPV30） in BCL treatment was reduced by 58.3%-73.1% compared with CN treatment. In concIusion, B. amy-loliquefaciens is a feasibIe Iow-cost biofertiIizer for sustalnabIe vegetabIe farming with a great potential for starch wastewater utiIization.展开更多
[Objective] The study aimed at exploring the relationship among the agronomic characters of B. juncea in western China, in order to provide scientific basis for the breeding of B. juncea in western China. [Method] 39 ...[Objective] The study aimed at exploring the relationship among the agronomic characters of B. juncea in western China, in order to provide scientific basis for the breeding of B. juncea in western China. [Method] 39 B. juncea materials from western China were used for the canonical correlation analysis, and canonical correlations between each pair of the four ecological character （containing 18 variables） were verified, including yield characters （5 variables）, caulis characters （6 variables）, branch characters （3 variables） and pod characters （3 variables）. [Result] Yield per plant of B. juncea in western China suffered a tremendous influence from effective pod number per plant while was not significantly affected by the total pod number per plant, seed number per pod and 1 000-seed weight; the most important character related with the yield character of B. juncea in western China was caulis character, followed by the branch character and pod character; yield characters, caulis characters, branch characters and pod characters of B. juncea in western China were closely correlated. [Conclusion] In order to improve the yield characters of B. juncea in western China, caulis characters should be focused on, followed by branch characters and pod characters; rapeseed varieties with high performance in total pod number per plant and effective pod number per plant should be chosen through the perspectives of effective branch number, plant height, pod number of main inflorescence, fruit stalk number of main inflorescence and other traits, while rapeseed varieties with high performance in seed number per pod and 1 000-seed weight should be chosen through the perspectives of beak length and other traits.展开更多
1973年,本院发现芥菜型油菜雄性不育株后,经连续几年研究,1975年育成了欧新 A 不育系,欧新 B 保持系和74243—6恢复系,实现了芥菜型“三系”配套。多年来连续测定表明,育成的芥菜型“三系”表现育性稳定,欧新 A 不育系的不育株率达100%...1973年,本院发现芥菜型油菜雄性不育株后,经连续几年研究,1975年育成了欧新 A 不育系,欧新 B 保持系和74243—6恢复系,实现了芥菜型“三系”配套。多年来连续测定表明,育成的芥菜型“三系”表现育性稳定,欧新 A 不育系的不育株率达100%,单株自交结实指数平均在0.000—0.103之间。恢复株率为99.54～100%,F_1杂种有较强的苗期优势,也有种子产量和含油量优势。比芥菜型地方良种昆明高棵增产19.2～34.8%,含油量提高6.58～8.23%。芥菜型“三系”的育成,填补了我国芥菜型杂优利用的空白,势将推动芥菜型油菜杂优利用的研究。展开更多
Anthocyanins confer the wide range of colors for plants and also play beneficial health roles as potentially protective factors against heart disease and cancer. Brassica juncea is cultivated as an edible oil resource...Anthocyanins confer the wide range of colors for plants and also play beneficial health roles as potentially protective factors against heart disease and cancer. Brassica juncea is cultivated as an edible oil resource and vegetable crop worldwide, thus elucidating the anthocyanin biosynthetic pathway would be helpful to improve the nutritional quality of Brassica juncea through the breeding and cultivating of high anthocyanin content varieties. Herein, 129 genes in B. juncea were identified as orthologs of 41 anthocyanin biosynthetic genes(ABGs) in Arabidopsis thaliana by comparative genomic analyses. The B. juncea ABGs have expanded by whole genome triplication and subsequent allopolyploidizatoin, but lost mainly during the whole genome triplication between B. rapa/B. nigra and A. thaliana, rather than the allopolyploidization process between B. juncea and B. rapa/B. nigra, leading to different copy numbers retention of A. thaliana homologous genes. Although the overall expansion levels ABGs were similar to the whole genome, more negative regulatory genes were retained in the anthocyanin biosynthesis regulatory system. Transcriptional analysis of B. juncea with different anthocyanin accumulation showed that BjDFR, BjTT19, BjTT8 are significantly up-regulated in plants with purple leaves as compared with green leaves. The overexpression of BjTT8 and these target genes which were involved in late anthocyanin biosynthesis and transport might account for increasing levels of anthocyanin accumulation in purple leaves. Our results could promote the understanding of the genetic mechanism of anthocyanin biosynthesis in B. juncea.展开更多
基金supported by grants from the National Natural Science Foundation of China(32172547).
文摘Photoperiod and temperature are crucial factors that trigger flowering in Brassica juncea(B.juncea).However,the underlying regulatory mechanisms remain poorly understood.The MADS-box transcription factor AGL18 acts as a pivotal repressor of floral transition and functions redundantly with AGL15.In this study,we isolated BjuAGL18-1 from B.juncea and identified two unique transcripts,resulting in two distinct proteins:a full-length protein,BjuAGL18-1L,and a truncated protein,BjuAGL18-1S.Further investigation showed that the two isoforms had similar subcellular localizations but different expression patterns in various plant tissues.Notably,BjuAGL18-1L and BjuAGL18-1S were abundantly induced under short-and long-day photoperiods,respectively.BjuAGL18-1L overexpression in B.juncea and Arabidopsis thaliana(A.thaliana)led to late flowering,whereas BjuAGL18-1S overexpression resulted in early flowering.Yeast two-hybrid,bimolecular fluorescent complementation,and luciferase complementation assays showed that BjuAGL18-1L,but not BjuAGL18-1S(which lacked the EAR motif),interacted with the co-repressor BjuAFR2 and the histone deacetylase BjuHDA9 to form a multiprotein complex.Further analysis indicated that BjuAGL18-1L could also form a complex with BjuAGL15 and bind to the BjuFUL promoter,thus inhibiting its expression.However,BjuAGL18-1S interacted with BjuAGL18-1L to form heterodimers,which attenuated their activities,likely by disrupting their binding to target genes,resulting in accelerated flowering progression.These results suggest that BjuAGL18-1 is involved in photoperiod-induced flowering via different regulatory mechanisms in B.juncea.
基金supported by grants from the National Natural Science Foundation of China(32002056)the Science and Technology Research Key Project of Henan Province,China(242102111138)。
文摘The potherb mustard Xuecai(XC)cultivar is a cruciferous vegetable that is popular either fresh or pickled.Due to the deep notches in the edges of leaves in mustard XC,this plant can be said to have multipinnately lobed leaves.The net photosynthesis of lobed leaves is significantly greater than that of simple leaves.However,the molecular mechanism of leaf shape variation has not been determined.Here,we used HiFi and Hi-C data to assemble the XC genome.The genome was 961.72 Mb in size,with a contig N50 value of 6.565 Mb.The XC genome was compared with four previously sequenced mustard genomes,and the genomic collinearity regions,SNPs,and indels were identified.Five BjRCO genes were found on chromosome(Chr.)A10 in potherb mustard XC when the BjRCO gene locus was compared against other sequenced B.juncea genomes.Segmental duplication was found to contribute to the BjRCO gene copy number.The transcript expression of BjRCO genes was greater in multipinnately lobed leaves than in sawtooth-like leaves.Together,these findings indicate that both the greater copy number and the expression level of BjRCO genes regulate leaf shape from simple to complex in B.juncea.Gene editing of the BjRCO gene from XC changed the leaf shape from multipinnately lobed to simple.The high-quality XC genome sequence not only provides new insight into B.juncea leaf-type genomics but also helps in deciphering leaf shape variation.Our study provides insights into the variation and evolution of important traits in Brassica plants through a comparative analysis of the sequenced genomes.
基金supported by the National Natural Science Foundation of China(U21A20236,32072664)the Natural Science Foundation of Hunan Province,China(2022RC3053,2021JC0001,2021RC3086,2022NK2009)+1 种基金the China Agriculture Research System(CARS-01-30)the Innovation Foundation for Graduate of Hunan Agricultural University,China(2023XC116)。
文摘Elucidating crops'physiological and molecular mechanisms to adapt to low nitrogen environment and promoting nitrogen transfer from senescent leaves to new leaves is crucial in improving Brassica's nitrogen use efficiency(NUE).Glutamine synthetase gene(GS)plays a vital role in helping plants reassimilate ammonium released from protein degradation in leaves,and it was the focus of our research on this topic.In this study,we identified high(H141)and low(L65)NUE genotypes of Brassica juncea with different responses to low-nitrogen stress.We found that H141 has a lower nitrate content but higher ammonium and free amino acid contents as well as higher nitrate reductase and GS activities in the shoots.These physiological indicators are responsible for the high NUE of H141.Wholegenome resequencing data revealed that 5,880 genes associated with NUE are polymorphic between H141 and L65.These genes participate in various amino acid,carbohydrate,and energy metabolic pathways.Haplotype analysis revealed two haplotypes for BjuB05.GS1.4,Hap1 and Hap2,which have multiple single nucleotide polymorphisms or insertions/deletions in the regulatory regions of the 5′and 3′untranslated regions and introns.Furthermore,the shoot NUE of Hap1 is significantly lower than that of Hap2.These two haplotypes of BjuB05.GS1.4 lead to differences in the shoot NUEs of different genetic populations of mustard and are associated with the local soil nitrogen content,suggesting that they might help mustard to adapt to different geographic localities.In conclusion,the results of our study shed light on the physiological and molecular mechanisms underlying different mustard NUE genotypes and demonstrate the enormous potential of NUE breeding in B.juncea.
基金funded by the Scientific and Technological Key Program of Guizhou Province, China (Qiankehezhicheng [2022] Key 031)the National Natural Science Foundation of China (32160483 and 32360497)+2 种基金the Post-Funded Project for the National Natural Science Foundation of China from Guizhou University ([2023]093)the Key Laboratory of Molecular Breeding for Grain and Oil Crops in Guizhou Province, China (Qiankehezhongyindi [2023]008)the Key Laboratory of Functional Agriculture of Guizhou Provincial Higher Education Institutions, China (Qianjiaoji [2023] 007)。
文摘Rapeseed mustard(Brassica juncea L.) is the third most important oilseed crop in the world, but the geneticmechanism underlying its massive phenotypic variation remains largely unexplored. In this study, specific length amplified fragment sequencing(SLAF-Seq) was used to resequence a population comprising 197 F8recombinantinbred lines(RILs) derived from a cross between vegetable-type Qichi881 and oilseed-type YufengZC of B. juncea. In total, 438,895 high-quality SLAFs were discovered, 47,644 of which were polymorphic, and 3,887 of the polymorphic markers met the requirements for genetic map construction. The final map included 3,887 markers on 18 linkage groups and was 1,830.23 centiMorgan(cM) in length, with an average distance of 0.47 cM between adjacent markers. Using the newly constructed high-density genetic map, a total of 53 QTLs for erucicacid(EA), oleic acid(OA), and linolenic acid(LNA) were detected and integrated into eight consensus QTLswith two for each of these traits. For each of these three traits, two candidate genes were cloned and sequence analysis indicated colocalization with their respective consensus QTLs. The co-dominant allele-specific markers for Bju.FAD3.A03 and Bju.FAD3.B07 were developed and showed co-localization with their consensus QTLs andco-segregation with LNA content, further supporting the results of QTL mapping and bioinformatic analysis. Theexpression levels of the cloned homologous genes were also determined, and the genes were tightly correlatedwith the EA, OA and LNA contents of different lines. The results of this study will facilitate the improvement offatty acid traits and molecular breeding of B. juncea. Further uses of the high-density genetic map created in this study are also discussed.
基金Supported by Key Research Program of the Chinese Academy of Sciences(KZZD-EW-09-3,KZZD-EW-11-03)National Science and Technology Major Project(2014ZX07204-005)Special Fund of the National Academy Alliance(2012-1)~~
文摘In this study, Bacil us amyloliquefaciens A3 was continual y incubated in shake fIasks contalning wastewater from sweet potato starch production as an ef-fective biofertiIizer for cuItivation of Brassica juncea var. multiceps（XueIihong）. Based on pot experiments in the greenhouse, the effects of chemical fertiIizers （CN）, biofertiIizer （BF）, inactivated broth （BI）, starch wastewater （SW） and the combination of biofertiIizer and chemical fertiIizer （BC） on the yield, NO3- content and NO2- con-tent of XueIihong, soiI physicochemical properties and N2O emission were investi-gated. The resuIts showed that the yield of XueIihong in BC and CN treatments was improved by five times compared with CK; BF and SW treatments had insignifi-cant impact on the yield of XueIihong. Compared with CN treatment, BCL treatment exhibited simiIar improving effects on the yield of XueIihong, in which NO3- content of XueIihong and soiI was reduced by 16.4%-73.6% and 22%-29%, which reduced the risk of nitrogen eIuviations in soiI; average N2O fIux （FPV30） in BCL treatment was reduced by 58.3%-73.1% compared with CN treatment. In concIusion, B. amy-loliquefaciens is a feasibIe Iow-cost biofertiIizer for sustalnabIe vegetabIe farming with a great potential for starch wastewater utiIization.
基金Supported by National Natural Science Foundation(30760122)National High-Tech Research and Development Program(863Program)(2009AA101105)+1 种基金Faculty Construction of 211 Project(SZTD-211-02)Project of Introducing Advanced Agricultural Science and Technology of Ministry of Agriculture(948Program)(2010-Z54)~~
文摘[Objective] The study aimed at exploring the relationship among the agronomic characters of B. juncea in western China, in order to provide scientific basis for the breeding of B. juncea in western China. [Method] 39 B. juncea materials from western China were used for the canonical correlation analysis, and canonical correlations between each pair of the four ecological character （containing 18 variables） were verified, including yield characters （5 variables）, caulis characters （6 variables）, branch characters （3 variables） and pod characters （3 variables）. [Result] Yield per plant of B. juncea in western China suffered a tremendous influence from effective pod number per plant while was not significantly affected by the total pod number per plant, seed number per pod and 1 000-seed weight; the most important character related with the yield character of B. juncea in western China was caulis character, followed by the branch character and pod character; yield characters, caulis characters, branch characters and pod characters of B. juncea in western China were closely correlated. [Conclusion] In order to improve the yield characters of B. juncea in western China, caulis characters should be focused on, followed by branch characters and pod characters; rapeseed varieties with high performance in total pod number per plant and effective pod number per plant should be chosen through the perspectives of effective branch number, plant height, pod number of main inflorescence, fruit stalk number of main inflorescence and other traits, while rapeseed varieties with high performance in seed number per pod and 1 000-seed weight should be chosen through the perspectives of beak length and other traits.
文摘1973年,本院发现芥菜型油菜雄性不育株后,经连续几年研究,1975年育成了欧新 A 不育系,欧新 B 保持系和74243—6恢复系,实现了芥菜型“三系”配套。多年来连续测定表明,育成的芥菜型“三系”表现育性稳定,欧新 A 不育系的不育株率达100%,单株自交结实指数平均在0.000—0.103之间。恢复株率为99.54～100%,F_1杂种有较强的苗期优势,也有种子产量和含油量优势。比芥菜型地方良种昆明高棵增产19.2～34.8%,含油量提高6.58～8.23%。芥菜型“三系”的育成,填补了我国芥菜型杂优利用的空白,势将推动芥菜型油菜杂优利用的研究。
基金funded by the National Key Research and Development Program of China(2016YFD0100202)the Natural Science Foundation of Hunan Province,China(2016JJ1010)the Scientific Research Fund of Hunan Provincial Education Department,China(18C0305,17K035,17C0652,and 17C0653)。
文摘Anthocyanins confer the wide range of colors for plants and also play beneficial health roles as potentially protective factors against heart disease and cancer. Brassica juncea is cultivated as an edible oil resource and vegetable crop worldwide, thus elucidating the anthocyanin biosynthetic pathway would be helpful to improve the nutritional quality of Brassica juncea through the breeding and cultivating of high anthocyanin content varieties. Herein, 129 genes in B. juncea were identified as orthologs of 41 anthocyanin biosynthetic genes(ABGs) in Arabidopsis thaliana by comparative genomic analyses. The B. juncea ABGs have expanded by whole genome triplication and subsequent allopolyploidizatoin, but lost mainly during the whole genome triplication between B. rapa/B. nigra and A. thaliana, rather than the allopolyploidization process between B. juncea and B. rapa/B. nigra, leading to different copy numbers retention of A. thaliana homologous genes. Although the overall expansion levels ABGs were similar to the whole genome, more negative regulatory genes were retained in the anthocyanin biosynthesis regulatory system. Transcriptional analysis of B. juncea with different anthocyanin accumulation showed that BjDFR, BjTT19, BjTT8 are significantly up-regulated in plants with purple leaves as compared with green leaves. The overexpression of BjTT8 and these target genes which were involved in late anthocyanin biosynthesis and transport might account for increasing levels of anthocyanin accumulation in purple leaves. Our results could promote the understanding of the genetic mechanism of anthocyanin biosynthesis in B. juncea.
