In cultivated rice ( Oryza sativa L.), F-1 pollen sterility is controlled by at least 6 loci of the F, pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-b(j)/S-b(j) and its nea...In cultivated rice ( Oryza sativa L.), F-1 pollen sterility is controlled by at least 6 loci of the F, pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-b(j)/S-b(j) and its near-isogenic line TIST2 carrying S-b(i)/S-b(i) were used to develop the mapping population. One hundred and fifty-eight microsatellite markers were selected to survey T65 and TISL2. RM13 on chromosome 5 was found to be polymorphic between them. Cosegregation indicated that RM13 was closely linked with locus S-b. Eleven RFLP markers were selected on the corresponding region from the genetic map of Rice Genome Research Program (RGP) of Japan to convert into sequence-tagged site (STS) markers. Amplicon length polymorphism (ALP) was carried out, but none of them was found to be polymorphic between T65 and TISL2. Then PCR-based RFLP (PBR) was done using six 4-nucleotide recognizing restriction endonucleases. Polymorphism was detected when PCR products of R830STS and R2213SSTS were digested with Taq I. Genetic analysis indicated that the distance between locus S-b and markers, R830STS, RM13 and R2213SSTS were 3.3 cM (centi-Morgan), 5.2 cM and 5.5 cM, respectively. These PCR-based markers could be directly used in marker-assisted selection. The technical system combining genetic mapping and PCR-based marker-assisted selection will facilitate the development of molecular breeding.展开更多
Rhododendron simsii（Ericaeae：Rhododendron） has high ornamental value and ecological value.In this study,7 pairs of novel EST-SSR markers were developed from the genomic sequence of R.simsii,and they were used to in...Rhododendron simsii（Ericaeae：Rhododendron） has high ornamental value and ecological value.In this study,7 pairs of novel EST-SSR markers were developed from the genomic sequence of R.simsii,and they were used to investigate the genetic diversity of 32 natural R.simsii samples from Guifeng Mountain,Hubei Province.Results showed that a total of 31 polymorphic bands were amplified with allele number per locus of 4.43.Mean values of heterozygosity（Ho） and expected heterozygosity（He） were 0.679 58 and 0.723 14,respectively.This research will not only enrich the existing SSR database,but also lay a foundation for subsequent studies about molecular marker-assisted breeding,genetic diversity analysis,genetic structure analysis and phylogenetic analysis.展开更多
Chloroplast simple sequence repeat (cpSSR) markers in Citrus were developed and successfully used to analyze chloroplast genome inheritance of Citrus somatic hybrids. Twenty-two previously reported cpSSR primer pairs ...Chloroplast simple sequence repeat (cpSSR) markers in Citrus were developed and successfully used to analyze chloroplast genome inheritance of Citrus somatic hybrids. Twenty-two previously reported cpSSR primer pairs from pine (Pinus thunbergii Parl.), rice (Otyza sativa L.) and tobacco (Nicotiana tabacum L.) were tested in Citrus, nine of which could amplify intensive PCR products by agarose gel electrophoresis. Chloroplast genome inheritance of Citrus somatic hybrids from nine fusions was then analyzed, and five of the nine pre-screened primer pairs showed polymorphisms by polyacrylamide gel electrophoresis. The results revealed the random inheritance nature of chloroplast genome in all analyzed Citrus somatic hybrids, which was in agreement with previous reports based on RFLP or CAPS analyses. It was also shown that cpSSR is a more efficient tool in chloroplast genome analyses of somatic hybrids in higher plants, compared with the conventional RFLP or CAPS analyses.展开更多
Objctive The aim was to make better use of the EST-SSR resources of kiwifruit for further molecular biological studies and new EST-SSR marker development by screening and mining the SSR repeats in the EST database of ...Objctive The aim was to make better use of the EST-SSR resources of kiwifruit for further molecular biological studies and new EST-SSR marker development by screening and mining the SSR repeats in the EST database of kiwifruit （Actinidia spp. ） [ Method] 56 400 of EST sequences were randomly selected from EST（ Expressed Sequence Tag）sequences of kiwifruit in the database of NCBI. EST sequences were analyzed and the SSR（Microsatellite） was screened by using the SSRHunter software. [ Result] 7 939 SSRs were identified from the ran- domly selected kiwifruit EST resources, among which there were 5 131 （64.63%） dinucleotide, 1 237 （ 15.58% ） trinucleotide, 284 （ 3.58% ） tetra nucleotide, 397 （5.00%） pentanucleotide and 890 （ 11.21% ） hexanucleotide SSRs. Among the dinucleotide sequences, AG/CT repeat motif was accounted for 4 654（90.70% ）. The frequency of SSRs was approximately 1/2.48 kb, which could exist to 1 SSR in 7 unigenes. [ Conclusion] The dinucleotide repeats appeared to be the most abundant SSRs, followed by the trinucleotide and hexanucleotide repeats. Among them the repeat motif such as AG/CT was predominant in each type of SSRs.展开更多
[ Objective] Study on the phylogenetic analysis of the 16S rDNA and insecticidal characteristics of strain BH-1 isolated from diseased larva of Anoplophora glabripennis （Motseh.） [ Method ] The strain was identified...[ Objective] Study on the phylogenetic analysis of the 16S rDNA and insecticidal characteristics of strain BH-1 isolated from diseased larva of Anoplophora glabripennis （Motseh.） [ Method ] The strain was identified by routine method and inoculated onto healthy Anoplophora glabripennis （Motseh.） for observing insecticidal effect, further 16S DNA was amplified by the specific primers for sequencing and homology analysis. [ Result] The mortality of second instar ofAnoplophora glabripennis（ Motseh. ） reached 72.7% 8 d after 10^10cfu/ml BH-1 was inoculated. The homology of 16S DNA sequences between BH-1 and Serratia marcescens accessed in GenBank reached 99.5%. Combined with the results of routine identification, BH-1 was identified as S. marcescens. [Conclusion] BH-1 could be used for biological control ofAnoplophora glabripennis （Motsch.）.展开更多
The objectives of this study were to isolate and characterize microsatellites from a heat tolerant variety of snap bean (Phaseolus vulgaris L.) in order to generate polymorphic genetic markers linked to quantitative t...The objectives of this study were to isolate and characterize microsatellites from a heat tolerant variety of snap bean (Phaseolus vulgaris L.) in order to generate polymorphic genetic markers linked to quantitative trait loci for heat tolerance. A genomic library contained 400-800 bp inserts was constructed and screened for the presence of (GA/CT) n and (CA/GT) n repeats. The proportion of positive clones yielded estimated of 3.72×10 4 such dinucleotide repeats per genome, roughly comparable to the abundance reported in other eukaryotic genomes. Twenty_six positive clones were sequenced. In contrast to mammalian genomes, the (GA/CT) n motif was much more abundant than the (CA/GT) n motif in these clones. The (GA/CT) n repeats also showed longer average repeat length (mean n =10.4 versus 6.5), suggesting that they are better candidates for yielding polymorphic genetic markers in the snap bean genome.展开更多
文摘In cultivated rice ( Oryza sativa L.), F-1 pollen sterility is controlled by at least 6 loci of the F, pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-b(j)/S-b(j) and its near-isogenic line TIST2 carrying S-b(i)/S-b(i) were used to develop the mapping population. One hundred and fifty-eight microsatellite markers were selected to survey T65 and TISL2. RM13 on chromosome 5 was found to be polymorphic between them. Cosegregation indicated that RM13 was closely linked with locus S-b. Eleven RFLP markers were selected on the corresponding region from the genetic map of Rice Genome Research Program (RGP) of Japan to convert into sequence-tagged site (STS) markers. Amplicon length polymorphism (ALP) was carried out, but none of them was found to be polymorphic between T65 and TISL2. Then PCR-based RFLP (PBR) was done using six 4-nucleotide recognizing restriction endonucleases. Polymorphism was detected when PCR products of R830STS and R2213SSTS were digested with Taq I. Genetic analysis indicated that the distance between locus S-b and markers, R830STS, RM13 and R2213SSTS were 3.3 cM (centi-Morgan), 5.2 cM and 5.5 cM, respectively. These PCR-based markers could be directly used in marker-assisted selection. The technical system combining genetic mapping and PCR-based marker-assisted selection will facilitate the development of molecular breeding.
文摘Rhododendron simsii（Ericaeae：Rhododendron） has high ornamental value and ecological value.In this study,7 pairs of novel EST-SSR markers were developed from the genomic sequence of R.simsii,and they were used to investigate the genetic diversity of 32 natural R.simsii samples from Guifeng Mountain,Hubei Province.Results showed that a total of 31 polymorphic bands were amplified with allele number per locus of 4.43.Mean values of heterozygosity（Ho） and expected heterozygosity（He） were 0.679 58 and 0.723 14,respectively.This research will not only enrich the existing SSR database,but also lay a foundation for subsequent studies about molecular marker-assisted breeding,genetic diversity analysis,genetic structure analysis and phylogenetic analysis.
文摘Chloroplast simple sequence repeat (cpSSR) markers in Citrus were developed and successfully used to analyze chloroplast genome inheritance of Citrus somatic hybrids. Twenty-two previously reported cpSSR primer pairs from pine (Pinus thunbergii Parl.), rice (Otyza sativa L.) and tobacco (Nicotiana tabacum L.) were tested in Citrus, nine of which could amplify intensive PCR products by agarose gel electrophoresis. Chloroplast genome inheritance of Citrus somatic hybrids from nine fusions was then analyzed, and five of the nine pre-screened primer pairs showed polymorphisms by polyacrylamide gel electrophoresis. The results revealed the random inheritance nature of chloroplast genome in all analyzed Citrus somatic hybrids, which was in agreement with previous reports based on RFLP or CAPS analyses. It was also shown that cpSSR is a more efficient tool in chloroplast genome analyses of somatic hybrids in higher plants, compared with the conventional RFLP or CAPS analyses.
基金Supported by the National Natural Science Foundation of China(30660113,30860167)~~
文摘Objctive The aim was to make better use of the EST-SSR resources of kiwifruit for further molecular biological studies and new EST-SSR marker development by screening and mining the SSR repeats in the EST database of kiwifruit （Actinidia spp. ） [ Method] 56 400 of EST sequences were randomly selected from EST（ Expressed Sequence Tag）sequences of kiwifruit in the database of NCBI. EST sequences were analyzed and the SSR（Microsatellite） was screened by using the SSRHunter software. [ Result] 7 939 SSRs were identified from the ran- domly selected kiwifruit EST resources, among which there were 5 131 （64.63%） dinucleotide, 1 237 （ 15.58% ） trinucleotide, 284 （ 3.58% ） tetra nucleotide, 397 （5.00%） pentanucleotide and 890 （ 11.21% ） hexanucleotide SSRs. Among the dinucleotide sequences, AG/CT repeat motif was accounted for 4 654（90.70% ）. The frequency of SSRs was approximately 1/2.48 kb, which could exist to 1 SSR in 7 unigenes. [ Conclusion] The dinucleotide repeats appeared to be the most abundant SSRs, followed by the trinucleotide and hexanucleotide repeats. Among them the repeat motif such as AG/CT was predominant in each type of SSRs.
基金Co-constructed Program of Beijing Education Committee for Scientific Research BaseResearch Fund for the Doctoral Program of Higher Education (20030022015)Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT0607)~~
文摘[ Objective] Study on the phylogenetic analysis of the 16S rDNA and insecticidal characteristics of strain BH-1 isolated from diseased larva of Anoplophora glabripennis （Motseh.） [ Method ] The strain was identified by routine method and inoculated onto healthy Anoplophora glabripennis （Motseh.） for observing insecticidal effect, further 16S DNA was amplified by the specific primers for sequencing and homology analysis. [ Result] The mortality of second instar ofAnoplophora glabripennis（ Motseh. ） reached 72.7% 8 d after 10^10cfu/ml BH-1 was inoculated. The homology of 16S DNA sequences between BH-1 and Serratia marcescens accessed in GenBank reached 99.5%. Combined with the results of routine identification, BH-1 was identified as S. marcescens. [Conclusion] BH-1 could be used for biological control ofAnoplophora glabripennis （Motsch.）.
文摘The objectives of this study were to isolate and characterize microsatellites from a heat tolerant variety of snap bean (Phaseolus vulgaris L.) in order to generate polymorphic genetic markers linked to quantitative trait loci for heat tolerance. A genomic library contained 400-800 bp inserts was constructed and screened for the presence of (GA/CT) n and (CA/GT) n repeats. The proportion of positive clones yielded estimated of 3.72×10 4 such dinucleotide repeats per genome, roughly comparable to the abundance reported in other eukaryotic genomes. Twenty_six positive clones were sequenced. In contrast to mammalian genomes, the (GA/CT) n motif was much more abundant than the (CA/GT) n motif in these clones. The (GA/CT) n repeats also showed longer average repeat length (mean n =10.4 versus 6.5), suggesting that they are better candidates for yielding polymorphic genetic markers in the snap bean genome.
