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
Ecotilling is a new approach based on enzyme-mediated heteroduplex cleavage to discover DNA polymorphisms in natural population. We used mung bean nuclease（MBN） instead of routinely used CELI to cleave single base p...Ecotilling is a new approach based on enzyme-mediated heteroduplex cleavage to discover DNA polymorphisms in natural population. We used mung bean nuclease（MBN） instead of routinely used CELI to cleave single base pair mismatches in heteroduplex DNA templates. Nested set of primers were designed to amplify targeted region to avoid the influence of the variation in quality and quantity of the genomic DNA. To reduce the costs in fluorescently labeled primers, we added M13 adapter to 5＇end of gene specific primers to make IRD dye labeled M13 forward and reverse primers possibly universal for different genes. A Brassica rapa ZIP gene homologue was subjected to the analysis to practise the feasibility of the method in polymorphisms detection. Our experiment showed this method is efficient in discovering DNA polymorphisms in Brassica rapa natural population.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.
文摘Ecotilling is a new approach based on enzyme-mediated heteroduplex cleavage to discover DNA polymorphisms in natural population. We used mung bean nuclease（MBN） instead of routinely used CELI to cleave single base pair mismatches in heteroduplex DNA templates. Nested set of primers were designed to amplify targeted region to avoid the influence of the variation in quality and quantity of the genomic DNA. To reduce the costs in fluorescently labeled primers, we added M13 adapter to 5＇end of gene specific primers to make IRD dye labeled M13 forward and reverse primers possibly universal for different genes. A Brassica rapa ZIP gene homologue was subjected to the analysis to practise the feasibility of the method in polymorphisms detection. Our experiment showed this method is efficient in discovering DNA polymorphisms in Brassica rapa natural population.
