A genetic linkage map of Brassica rapa ssp. pekinensis was constructed with 186 AFLP （amplified fragment length polymorphism） markers by using a doubled-haploid （DH） population with 183 individuals. The individual...A genetic linkage map of Brassica rapa ssp. pekinensis was constructed with 186 AFLP （amplified fragment length polymorphism） markers by using a doubled-haploid （DH） population with 183 individuals. The individuals were derived from F1 which was developed by crossing a bolting resistant DH line Y-177-12 and an easy bolting DH line Y195-93a. AFLPs were generated by the use of restriction enzymes EcoR Ⅰ and Mse Ⅰ . The segregation of each marker and linkage was analyzed by using JoinMap version 3.0. Mapped markers were aligned in ten linkage groups which covered 887.8 cM with an average marker interval of 4.47 cM. Markers showing skewed segregation ratio were clustered in six LGs. Quantitative trait loci （QTL） were mapped for bolting resistance by using MAPQTL 4.0 package. Four QTLs explaining from 7.0 to 9.4% of the total variation were detected, all of them increase bolting resistance. These mapped QTLs could be used to develop a marker assisted selection programme for bolting resistance breeding.展开更多
Chinese cabbage is an economically important Brassica vegetable worldwide, and clubroot, which is caused by the soilborne protist plant pathogen Plasmodiophora brassicae is regarded as a destructive disease to Brassic...Chinese cabbage is an economically important Brassica vegetable worldwide, and clubroot, which is caused by the soilborne protist plant pathogen Plasmodiophora brassicae is regarded as a destructive disease to Brassica crops. Previous studies on the gene transcripts related to Chinese cabbage resistance to clubroot mainly employed RNA-seq technology,although it cannot provide accurate transcript assembly and structural information. In this study, PacBio RS II SMRT sequencing was used to generate full-length transcriptomes of mixed roots at 0, 2, 5, 8, 13, and 22 days after P. brassicae infection in the clubroot-resistant line DH40R. Overall, 39 376 high-quality isoforms and 26 270 open reading frames(ORFs) were identified from the SMRT sequencing data. Additionally, 426 annotated long noncoding RNAs(lncRNAs),56 transcription factor(TF) families, 1 883 genes with poly(A) sites and 1 691 alternative splicing(AS) events were identified. Furthermore, 1 201 of the genes had at least one AS event in DH40R. A comparison with RNA-seq data revealed six differentially expressed AS genes(one for disease resistance and five for defensive response) that are potentially involved in P. brassicae resistance. The results of this study provide valuable resources for basic research on clubroot resistance in Chinese cabbage.展开更多
文摘A genetic linkage map of Brassica rapa ssp. pekinensis was constructed with 186 AFLP （amplified fragment length polymorphism） markers by using a doubled-haploid （DH） population with 183 individuals. The individuals were derived from F1 which was developed by crossing a bolting resistant DH line Y-177-12 and an easy bolting DH line Y195-93a. AFLPs were generated by the use of restriction enzymes EcoR Ⅰ and Mse Ⅰ . The segregation of each marker and linkage was analyzed by using JoinMap version 3.0. Mapped markers were aligned in ten linkage groups which covered 887.8 cM with an average marker interval of 4.47 cM. Markers showing skewed segregation ratio were clustered in six LGs. Quantitative trait loci （QTL） were mapped for bolting resistance by using MAPQTL 4.0 package. Four QTLs explaining from 7.0 to 9.4% of the total variation were detected, all of them increase bolting resistance. These mapped QTLs could be used to develop a marker assisted selection programme for bolting resistance breeding.
基金supported by the National Natural Science Foundation of China (31872945 and 31801874)the earmarked fund for China Agricultural Research System (CARS-23-G15)+1 种基金the Funds for Distinguished Young Scientists from Henan Academy of Agricultural Sciences, China (2021JQ03)the Innovation Team of Henan Academy of Agricultural Sciences, China (2021TD06)。
文摘Chinese cabbage is an economically important Brassica vegetable worldwide, and clubroot, which is caused by the soilborne protist plant pathogen Plasmodiophora brassicae is regarded as a destructive disease to Brassica crops. Previous studies on the gene transcripts related to Chinese cabbage resistance to clubroot mainly employed RNA-seq technology,although it cannot provide accurate transcript assembly and structural information. In this study, PacBio RS II SMRT sequencing was used to generate full-length transcriptomes of mixed roots at 0, 2, 5, 8, 13, and 22 days after P. brassicae infection in the clubroot-resistant line DH40R. Overall, 39 376 high-quality isoforms and 26 270 open reading frames(ORFs) were identified from the SMRT sequencing data. Additionally, 426 annotated long noncoding RNAs(lncRNAs),56 transcription factor(TF) families, 1 883 genes with poly(A) sites and 1 691 alternative splicing(AS) events were identified. Furthermore, 1 201 of the genes had at least one AS event in DH40R. A comparison with RNA-seq data revealed six differentially expressed AS genes(one for disease resistance and five for defensive response) that are potentially involved in P. brassicae resistance. The results of this study provide valuable resources for basic research on clubroot resistance in Chinese cabbage.
