Using SRAP(sequence-related amplified polymorphism)markers a genetic linkage map of cucumber was constructed with a population consisting of 138 F_(2) individuals derived from a cross of the two cucumber lines,S06 and...Using SRAP(sequence-related amplified polymorphism)markers a genetic linkage map of cucumber was constructed with a population consisting of 138 F_(2) individuals derived from a cross of the two cucumber lines,S06 and S52.In the survey of parental polymorphisms with 182 primer combinations,64 polymorphism-revealing primer pairs were screened out,which generated totally 108 polymorphic bands with an average of 1.7 bands per primer pair and at most 6 bands from one primer pair.The constructed molecular linkage map included 92 loci,distributed in seven linkage groups and spanning 1164.2 cM in length with an average genetic distance of 12.6 cM between two neighboring loci.Based on this linkage map,the quantitative trait loci(QTL)for the lateral branch number(lbn)and the lateral branch average length(lbl)in cucumber were identified by QTLMapper1.6.A major QTL lbn1 located between ME11SA4B and ME5EM5 in LG2 could explain 10.63%of the total variation with its positively effecting allele from S06.A major QTL lbl1 located between DC1OD3 and DC1EM14 in LG2 could account for 10.38%of the total variation with its positively effecting allele from S_(06).展开更多
A group of 224 recombinant inbred lines (RILs) was derived from a narrow cross between 2 cucumber (Cucumis sativus L.) lines, namely, S94 (Northern China type with weak lateral branch growth potential and early latera...A group of 224 recombinant inbred lines (RILs) was derived from a narrow cross between 2 cucumber (Cucumis sativus L.) lines, namely, S94 (Northern China type with weak lateral branch growth potential and early lateral branch sprouting time) and S06 (Northern European type with strong lateral branch growth potential and late lateral branch sprouting time). These lines were then used for investigating lateral branch-related traits. A total of 36 quantitative trait loci (QTLs) were detected for the following 4 lateral branch-related traits: lateral branch average length (LBAL), lateral branch total length (LBTL), lateral branch number (LBN), and first lateral branch node (FLBN). Further, each QTL explained 3.1% (lbtl2.1, spring) to 32.3% (lbn2.3, spring) of the observed phenotypic variance. Eleven QTLs (lbal1.1, lbtl1.1, lbn1.2, flbn1.2, etc.) for different traits were found to be clustered on the e23m18d-ME23EM6c section (7.4 cM) of linkage group (LG) 1; further, 15 QTLs (lbal2.1, lbtl2.1, lbn2.1, flbn2.1, etc.) were found to be clustered on the S94A1-ME4SA4a section (13.9 cM) of LG2. Twenty-one QTLs explained more than 10% of the phenotypic variance. Moreover, lbtl1.3 (autumn, 26.2%, logarithm of odds (LOD) = 17.4; spring, 26.9%, LOD = 17.9) had stable position and contribution in both seasons. Several se-quence-anchor markers (CMBR40, F, CS30, S94A1, CSWTA11B, etc.) were closely linked with some QTLs for LBAL, LBTL, LBN, and FLBN, which can be used for the marker-assisted selection to improve the plant architecture in cucumber breeding.展开更多
Tnt1 is an active retrotransposon originally identified in tobacco(Nicotiana tabacum L.)(Grandbastien et al.,1989),but its transposition activity could be activated through tissue culture in other plant species.The in...Tnt1 is an active retrotransposon originally identified in tobacco(Nicotiana tabacum L.)(Grandbastien et al.,1989),but its transposition activity could be activated through tissue culture in other plant species.The insertions are stable and inheritable in the progeny,which has made it a valuable and versatile tool for developing insertional mutagenesis libraries in several plant species.Here,we explored its utility for mutagenesis in cucumber(Cucumis sativus L.).T_3 Tnt1 transgenic cucumber plants were subjected to tissue culture to regenerate self-pollinated progeny.With PCR and analyses and Southern hybridization,we found regenerated plants maintained the original Tnt1 insertion and created new insertions suggesting characteristic re-transposition activity of Tnt1 during this process.Using genome walking,some flanking sequences of Tnt1 insertions were recovered in regenerated plants.The results demonstrated that Tnt1 could be stably inherited and re-transposable during tissue culture in cucumber and that it is feasible to use for developing an insertional mutagenesis library for cucumber.展开更多
Plants are exposed to many potentially pathogenic microbes in the environment, but each species is only susceptible to a limited number of pathogens. The broad resistance is referred to as nonhost re-sistance. To date...Plants are exposed to many potentially pathogenic microbes in the environment, but each species is only susceptible to a limited number of pathogens. The broad resistance is referred to as nonhost re-sistance. To date, little is known about the underlying mechanism of nonhost resistance and the sig-naling transduction process. Here we describe a simple method for isolating Arabidopsis nonhost re-sistance mutants against a nonadapted bacterial pathogen. A RAP2.6 promoter-driven LUC reporter system was developed to replace the tedious bacterial growth assay during the primary screening. The RAP2.6-LUC reporter gene is normally induced by the virulent bacterium Pseudomonas syringae pv tomato but not the nonadapted bacterium P. syringae pv phaseolicola. By using this method we iso-lated 4 mutants displaying strong reporter activity in response to P. syringae pv phaseolicola, which were characterized in some details. ebs1, ebs2, ebs3, and ebs4 (enhanced bacterial susceptibility) were compromised in resistance against P. syringae pv phaseolicola and/or P. syringae pv tomato. In addi-tion, ebs4 showed enhanced hypersensitive response to the incompatible bacterium P. syringae pv tomato (avrB). These results demonstrated that the method is suited for large scale screening for nonhost resistance mutants.展开更多
基金This work was support ed by the Shanghai Municipal Scientifi c&Technological Commission(Grant Nos.033107019)Shanghai Municipal Agricultural Commission(Grant Nos 2003-2-1-2).
文摘Using SRAP(sequence-related amplified polymorphism)markers a genetic linkage map of cucumber was constructed with a population consisting of 138 F_(2) individuals derived from a cross of the two cucumber lines,S06 and S52.In the survey of parental polymorphisms with 182 primer combinations,64 polymorphism-revealing primer pairs were screened out,which generated totally 108 polymorphic bands with an average of 1.7 bands per primer pair and at most 6 bands from one primer pair.The constructed molecular linkage map included 92 loci,distributed in seven linkage groups and spanning 1164.2 cM in length with an average genetic distance of 12.6 cM between two neighboring loci.Based on this linkage map,the quantitative trait loci(QTL)for the lateral branch number(lbn)and the lateral branch average length(lbl)in cucumber were identified by QTLMapper1.6.A major QTL lbn1 located between ME11SA4B and ME5EM5 in LG2 could explain 10.63%of the total variation with its positively effecting allele from S06.A major QTL lbl1 located between DC1OD3 and DC1EM14 in LG2 could account for 10.38%of the total variation with its positively effecting allele from S_(06).
基金Shanghai Leading Academic Discipline Project(Grant No.B209)
文摘A group of 224 recombinant inbred lines (RILs) was derived from a narrow cross between 2 cucumber (Cucumis sativus L.) lines, namely, S94 (Northern China type with weak lateral branch growth potential and early lateral branch sprouting time) and S06 (Northern European type with strong lateral branch growth potential and late lateral branch sprouting time). These lines were then used for investigating lateral branch-related traits. A total of 36 quantitative trait loci (QTLs) were detected for the following 4 lateral branch-related traits: lateral branch average length (LBAL), lateral branch total length (LBTL), lateral branch number (LBN), and first lateral branch node (FLBN). Further, each QTL explained 3.1% (lbtl2.1, spring) to 32.3% (lbn2.3, spring) of the observed phenotypic variance. Eleven QTLs (lbal1.1, lbtl1.1, lbn1.2, flbn1.2, etc.) for different traits were found to be clustered on the e23m18d-ME23EM6c section (7.4 cM) of linkage group (LG) 1; further, 15 QTLs (lbal2.1, lbtl2.1, lbn2.1, flbn2.1, etc.) were found to be clustered on the S94A1-ME4SA4a section (13.9 cM) of LG2. Twenty-one QTLs explained more than 10% of the phenotypic variance. Moreover, lbtl1.3 (autumn, 26.2%, logarithm of odds (LOD) = 17.4; spring, 26.9%, LOD = 17.9) had stable position and contribution in both seasons. Several se-quence-anchor markers (CMBR40, F, CS30, S94A1, CSWTA11B, etc.) were closely linked with some QTLs for LBAL, LBTL, LBN, and FLBN, which can be used for the marker-assisted selection to improve the plant architecture in cucumber breeding.
基金supported by the National Natural Science Foundation of China(No.31471156)the Agri-X Project of Shanghai Jiao Tong University(Agri-X2015002)the Shanghai Graduate Education and Innovation Program(Horticulture)
文摘Tnt1 is an active retrotransposon originally identified in tobacco(Nicotiana tabacum L.)(Grandbastien et al.,1989),but its transposition activity could be activated through tissue culture in other plant species.The insertions are stable and inheritable in the progeny,which has made it a valuable and versatile tool for developing insertional mutagenesis libraries in several plant species.Here,we explored its utility for mutagenesis in cucumber(Cucumis sativus L.).T_3 Tnt1 transgenic cucumber plants were subjected to tissue culture to regenerate self-pollinated progeny.With PCR and analyses and Southern hybridization,we found regenerated plants maintained the original Tnt1 insertion and created new insertions suggesting characteristic re-transposition activity of Tnt1 during this process.Using genome walking,some flanking sequences of Tnt1 insertions were recovered in regenerated plants.The results demonstrated that Tnt1 could be stably inherited and re-transposable during tissue culture in cucumber and that it is feasible to use for developing an insertional mutagenesis library for cucumber.
基金the Shanghai Leading Academic Discipline Project (Grant No. B209)a grant from Chinese Ministry of Science and Technology to Zhou Jian Min (Grant No. 2003AA210080)
文摘Plants are exposed to many potentially pathogenic microbes in the environment, but each species is only susceptible to a limited number of pathogens. The broad resistance is referred to as nonhost re-sistance. To date, little is known about the underlying mechanism of nonhost resistance and the sig-naling transduction process. Here we describe a simple method for isolating Arabidopsis nonhost re-sistance mutants against a nonadapted bacterial pathogen. A RAP2.6 promoter-driven LUC reporter system was developed to replace the tedious bacterial growth assay during the primary screening. The RAP2.6-LUC reporter gene is normally induced by the virulent bacterium Pseudomonas syringae pv tomato but not the nonadapted bacterium P. syringae pv phaseolicola. By using this method we iso-lated 4 mutants displaying strong reporter activity in response to P. syringae pv phaseolicola, which were characterized in some details. ebs1, ebs2, ebs3, and ebs4 (enhanced bacterial susceptibility) were compromised in resistance against P. syringae pv phaseolicola and/or P. syringae pv tomato. In addi-tion, ebs4 showed enhanced hypersensitive response to the incompatible bacterium P. syringae pv tomato (avrB). These results demonstrated that the method is suited for large scale screening for nonhost resistance mutants.