We have compared genetic diversity of 24 Chinese weak-winter, Swedish winter and spring B. napus accessions by inter-simple sequence repeats (ISSRs). By cluster analysis (UPGMA) based on 125 polymorphism bands amplifi...We have compared genetic diversity of 24 Chinese weak-winter, Swedish winter and spring B. napus accessions by inter-simple sequence repeats (ISSRs). By cluster analysis (UPGMA) based on 125 polymorphism bands amplified with 20 primers, the 24 accessions were divided into three groups. Six Swedish winter lines and eight Chinese weak-winter lines were in the group I and the groupⅡwere two Chinese weak-winter lines XiangyoulS and Bao81. The third group contained eight Swedish spring lines. Principal co-ordinates analysis (PCO) showed similar groupings to cluster analysis. Results from cluster analysis and PCO analysis showed very clearly that Chinese weak-winter, Swedish spring and winter accessions were distinguished from each other and Chinese weak-winter accessions in this study were genetically closer to Swedish winter accessions than to Swedish spring accessions. The Chinese weak-winter accessions had larger diversity than Swedish spring or winter accessions did. This study indicated that ISSR is a suitable and effective tool to evaluate genetic diversity among rapeseed germplasm.展开更多
Amplified inter simple sequence repeats （ISSR） markers were used to determine genetic relationships among mutant silkworm strains of Bombyx mori. Fifteen ISSR primers containing simple sequence repeat （SSR） motifs...Amplified inter simple sequence repeats （ISSR） markers were used to determine genetic relationships among mutant silkworm strains of Bombyx mori. Fifteen ISSR primers containing simple sequence repeat （SSR） motifs were used in this study. A total of 113 markers were produced among 20 mutant strains, of which 73.45% were found to be polymorphic. In selected mutant genetic stocks, the average number of observed allele was （1.7080 ± 0.4567）, effective alleles （1.5194 ± 0.3950） and genetic diversity （Ht） （0.2901 ± 0.0415）. The dendrogram produced using the unweighted pair group method with arithmetic means （UPGMA） and cluster analysis made using Nei＇s genetic distance resulted in the formation of one major group containing 6 groups separated 20 mutant silkworm strains. Therefore, ISSR amplification is a valuable method for determining the genetic variability among mutant silkworm strains. This efficient molecular marker would be useful for characterizing a considerable number of silkworm strains maintained at the germplasm center.展开更多
"Wu zhu yu", which is obtained from the dried unripe fruits of Tetradium ruticarpum(A. Jussieu) T. G. Hartley, has been used as a traditional Chinese medicine for treatment of headaches, abdominal colic, and..."Wu zhu yu", which is obtained from the dried unripe fruits of Tetradium ruticarpum(A. Jussieu) T. G. Hartley, has been used as a traditional Chinese medicine for treatment of headaches, abdominal colic, and hypertension for thousands of years. The present study was designed to assess the molecular genetic diversity among 25 collected accessions of T. ruticarpum(Wu zhu yu in Chinese) from different areas of China, based on inter-primer binding site(i PBS) markers and inter-simple sequence repeat(ISSR) markers. Thirteen ISSR primers generated 151 amplification bands, of which 130 were polymorphic. Out of 165 bands that were amplified using 10 iPBS primers, 152 were polymorphic. The iPBS markers displayed a higher proportion of polymorphic loci(PPL = 92.5%) than the ISSR markers(PPL = 84.9%). The results showed that T. ruticarpum possessed high loci polymorphism and genetic differentiation occurred in this plant. The combined data of iPBS and ISSR markers scored on 25 accessions produced five clusters that approximately matched the geographic distribution of the species. The results indicated that both iPBS and ISSR markers were reliable and effective tools for analyzing the genetic diversity in T. ruticarpum.展开更多
Inter-simple Sequence Repeat （ISSR） analysis was applied to assess the genetic diversity within and among five populations of mink from Liaoning Province. A total of 20 primers were screened, five selected primers p...Inter-simple Sequence Repeat （ISSR） analysis was applied to assess the genetic diversity within and among five populations of mink from Liaoning Province. A total of 20 primers were screened, five selected primers produced 35 discernible bands, with 30 （85.71%） being polymorphic, indicating high genetic diversity at the species level. The highest genetic diversity was observed in the brown mink population, whereas the lowest diversity was found in the standard-pitchy mink population. Based on genetic distance （1972）, a dendrogram was constructed by using UPGMA algorithm, and five populations were divided into two major groups. Group I consisted of only the standard-pitchy mink population, and Group II included other four populations, in Group II, sapphire mink was close to brown mink population. The results of genetic differentiation indicated that the genetic differentiation degree between populations was lower and the genetic variation primarily came from within populations. This paper showed that ISSR technique was a reliable tool that could be used to study genetic diversity in the mink.展开更多
Sugarcane is an important tropical crop, responsible for two thirds of the world sugar production, gaining actually importance as a source of biofuel. Drought tolerance is a very important feature considering the actu...Sugarcane is an important tropical crop, responsible for two thirds of the world sugar production, gaining actually importance as a source of biofuel. Drought tolerance is a very important feature considering the actual climate change scenario throughout the world. This study aimed to determine the genetic diversity between sugarcane varieties with contrasting features under drought. For this purpose, twelve ISSR primers were used to characterize nine sugarcane varieties under cultivation in different countries including selected drought resistant material from Northeast Brazil and two varieties from India as contrasting genotypes. 317 scorable bands were generated, among which 301 comprised polymorphic markers, with an average of 25 polymorphic bands per primer. In the generated dendrogram the accessions were placed in clusters, where cluster A included two varieties from India (Co331 and Co419), and B comprised plants eight Brazilian accessions and a ‘Barbado’ variety. Within this clade, drought tolerant and susceptible varieties were clearly separated. The present evaluation revealed important contrasting parental candidates regarding their drought response, very promising for future mapping approaches aiming the identification of quantitative trait loci (QTLs) associated to drought in sugarcane. The selected primers were used for the first time in sugarcane, representing valuable tools for future evaluations, with emphasis to diversity characterization and genetic mapping.展开更多
Soybean (</span><i><span style="font-family:Verdana;">Glycine</span></i> <i><span style="font-family:Verdana;">max</span></i><span style=&qu...Soybean (</span><i><span style="font-family:Verdana;">Glycine</span></i> <i><span style="font-family:Verdana;">max</span></i><span style="font-family:Verdana;">) is one of the most important crops in the world in terms of total production and usage. It is also among the least diverse species. The main objectives of the present study were to 1) assess the level of genetic variation among soybean (</span><i><span style="font-family:Verdana;">G.</span></i> <i><span style="font-family:Verdana;">max</span></i><span style="font-family:Verdana;">) accessions from different countries using Random Amplified Polymorphic DNA (RAPD) markers and 2) compare Inter Simple Sequence Repeats (ISSR) and RAPD marker systems in detecting polymorphic loci in soybeans (</span><i><span style="font-family:Verdana;">G.</span></i> <i><span style="font-family:Verdana;">max</span></i><span style="font-family:Verdana;">). Genomic DNAs from 108 soybeans (</span><i><span style="font-family:Verdana;">G.</span></i> <i><span style="font-family:Verdana;">max</span></i><span style="font-family:Verdana;">) accessions from 11 different gene pools were analyzed using several ISSR and RAPD primers. The average level of polymorphic loci detected with the RAPD primers was 35%. The soybean accessions from the China, Netherlands, and Canada gene pools were the least genetically variable with 25%, 26%, and 30% of polymorphic loci, respectively. Accessions from Hungary (43%) and France (48%) showed the highest level of polymorphism based on the RAPD analysis. Overall, RAPD data revealed that the accessions from different countries are closely related with 64% genetic distance values below 0.40. The levels of polymorphic loci detected with the RAPD and ISSR marker systems were in general moderate and similar even if they target different regions of the genome. A combination of different marker systems that include RAPD/ISSR, microsatellites (SSR), and SNPs should provide the most accurate information on genetic variation of soybean (</span><i><span style="font-family:Verdana;">G.</span></i> <i><span style="font-family:Verdana;">max</span></i><span style="font-family:Verdana;">) accessions.展开更多
文摘We have compared genetic diversity of 24 Chinese weak-winter, Swedish winter and spring B. napus accessions by inter-simple sequence repeats (ISSRs). By cluster analysis (UPGMA) based on 125 polymorphism bands amplified with 20 primers, the 24 accessions were divided into three groups. Six Swedish winter lines and eight Chinese weak-winter lines were in the group I and the groupⅡwere two Chinese weak-winter lines XiangyoulS and Bao81. The third group contained eight Swedish spring lines. Principal co-ordinates analysis (PCO) showed similar groupings to cluster analysis. Results from cluster analysis and PCO analysis showed very clearly that Chinese weak-winter, Swedish spring and winter accessions were distinguished from each other and Chinese weak-winter accessions in this study were genetically closer to Swedish winter accessions than to Swedish spring accessions. The Chinese weak-winter accessions had larger diversity than Swedish spring or winter accessions did. This study indicated that ISSR is a suitable and effective tool to evaluate genetic diversity among rapeseed germplasm.
文摘Amplified inter simple sequence repeats （ISSR） markers were used to determine genetic relationships among mutant silkworm strains of Bombyx mori. Fifteen ISSR primers containing simple sequence repeat （SSR） motifs were used in this study. A total of 113 markers were produced among 20 mutant strains, of which 73.45% were found to be polymorphic. In selected mutant genetic stocks, the average number of observed allele was （1.7080 ± 0.4567）, effective alleles （1.5194 ± 0.3950） and genetic diversity （Ht） （0.2901 ± 0.0415）. The dendrogram produced using the unweighted pair group method with arithmetic means （UPGMA） and cluster analysis made using Nei＇s genetic distance resulted in the formation of one major group containing 6 groups separated 20 mutant silkworm strains. Therefore, ISSR amplification is a valuable method for determining the genetic variability among mutant silkworm strains. This efficient molecular marker would be useful for characterizing a considerable number of silkworm strains maintained at the germplasm center.
基金supported by the National Science and Technology Major Projects for"Major New Drugs Innovation and Development" and the"Chinese Herbal Medicine Seeds and Seedlings Planting(breeding)Standard Platform Topics"(No.2012ZX09304006)
文摘"Wu zhu yu", which is obtained from the dried unripe fruits of Tetradium ruticarpum(A. Jussieu) T. G. Hartley, has been used as a traditional Chinese medicine for treatment of headaches, abdominal colic, and hypertension for thousands of years. The present study was designed to assess the molecular genetic diversity among 25 collected accessions of T. ruticarpum(Wu zhu yu in Chinese) from different areas of China, based on inter-primer binding site(i PBS) markers and inter-simple sequence repeat(ISSR) markers. Thirteen ISSR primers generated 151 amplification bands, of which 130 were polymorphic. Out of 165 bands that were amplified using 10 iPBS primers, 152 were polymorphic. The iPBS markers displayed a higher proportion of polymorphic loci(PPL = 92.5%) than the ISSR markers(PPL = 84.9%). The results showed that T. ruticarpum possessed high loci polymorphism and genetic differentiation occurred in this plant. The combined data of iPBS and ISSR markers scored on 25 accessions produced five clusters that approximately matched the geographic distribution of the species. The results indicated that both iPBS and ISSR markers were reliable and effective tools for analyzing the genetic diversity in T. ruticarpum.
文摘Inter-simple Sequence Repeat （ISSR） analysis was applied to assess the genetic diversity within and among five populations of mink from Liaoning Province. A total of 20 primers were screened, five selected primers produced 35 discernible bands, with 30 （85.71%） being polymorphic, indicating high genetic diversity at the species level. The highest genetic diversity was observed in the brown mink population, whereas the lowest diversity was found in the standard-pitchy mink population. Based on genetic distance （1972）, a dendrogram was constructed by using UPGMA algorithm, and five populations were divided into two major groups. Group I consisted of only the standard-pitchy mink population, and Group II included other four populations, in Group II, sapphire mink was close to brown mink population. The results of genetic differentiation indicated that the genetic differentiation degree between populations was lower and the genetic variation primarily came from within populations. This paper showed that ISSR technique was a reliable tool that could be used to study genetic diversity in the mink.
文摘Sugarcane is an important tropical crop, responsible for two thirds of the world sugar production, gaining actually importance as a source of biofuel. Drought tolerance is a very important feature considering the actual climate change scenario throughout the world. This study aimed to determine the genetic diversity between sugarcane varieties with contrasting features under drought. For this purpose, twelve ISSR primers were used to characterize nine sugarcane varieties under cultivation in different countries including selected drought resistant material from Northeast Brazil and two varieties from India as contrasting genotypes. 317 scorable bands were generated, among which 301 comprised polymorphic markers, with an average of 25 polymorphic bands per primer. In the generated dendrogram the accessions were placed in clusters, where cluster A included two varieties from India (Co331 and Co419), and B comprised plants eight Brazilian accessions and a ‘Barbado’ variety. Within this clade, drought tolerant and susceptible varieties were clearly separated. The present evaluation revealed important contrasting parental candidates regarding their drought response, very promising for future mapping approaches aiming the identification of quantitative trait loci (QTLs) associated to drought in sugarcane. The selected primers were used for the first time in sugarcane, representing valuable tools for future evaluations, with emphasis to diversity characterization and genetic mapping.
文摘Soybean (</span><i><span style="font-family:Verdana;">Glycine</span></i> <i><span style="font-family:Verdana;">max</span></i><span style="font-family:Verdana;">) is one of the most important crops in the world in terms of total production and usage. It is also among the least diverse species. The main objectives of the present study were to 1) assess the level of genetic variation among soybean (</span><i><span style="font-family:Verdana;">G.</span></i> <i><span style="font-family:Verdana;">max</span></i><span style="font-family:Verdana;">) accessions from different countries using Random Amplified Polymorphic DNA (RAPD) markers and 2) compare Inter Simple Sequence Repeats (ISSR) and RAPD marker systems in detecting polymorphic loci in soybeans (</span><i><span style="font-family:Verdana;">G.</span></i> <i><span style="font-family:Verdana;">max</span></i><span style="font-family:Verdana;">). Genomic DNAs from 108 soybeans (</span><i><span style="font-family:Verdana;">G.</span></i> <i><span style="font-family:Verdana;">max</span></i><span style="font-family:Verdana;">) accessions from 11 different gene pools were analyzed using several ISSR and RAPD primers. The average level of polymorphic loci detected with the RAPD primers was 35%. The soybean accessions from the China, Netherlands, and Canada gene pools were the least genetically variable with 25%, 26%, and 30% of polymorphic loci, respectively. Accessions from Hungary (43%) and France (48%) showed the highest level of polymorphism based on the RAPD analysis. Overall, RAPD data revealed that the accessions from different countries are closely related with 64% genetic distance values below 0.40. The levels of polymorphic loci detected with the RAPD and ISSR marker systems were in general moderate and similar even if they target different regions of the genome. A combination of different marker systems that include RAPD/ISSR, microsatellites (SSR), and SNPs should provide the most accurate information on genetic variation of soybean (</span><i><span style="font-family:Verdana;">G.</span></i> <i><span style="font-family:Verdana;">max</span></i><span style="font-family:Verdana;">) accessions.
