Acinetobacter(A.)baumannii is a Gram-negative,non-fermenting opportunistic pathogen increasingly implicated in nosocomial infections,particularly in intensive care units(ICUs).Its ability to acquire multidrug resistan...Acinetobacter(A.)baumannii is a Gram-negative,non-fermenting opportunistic pathogen increasingly implicated in nosocomial infections,particularly in intensive care units(ICUs).Its ability to acquire multidrug resistance(MDR),including to carbapenems,poses a major public health threat.Infections caused by A.baumannii-ranging from pneumonia to bloodstream and wound infections-are difficult to treat and associated with high mortality,especially in critically ill patients[1].展开更多
Objective] This study was conducted to verify the feasibiIity of ISSR marker for identifying genetic purity of bitter gourd hybrid, and thus to provide an effective method for seed purity test in production practices....Objective] This study was conducted to verify the feasibiIity of ISSR marker for identifying genetic purity of bitter gourd hybrid, and thus to provide an effective method for seed purity test in production practices. [Method] The DNA fin-gerprints of a bitter gourd cuItivar Xiuyu 1 and its parents were analyzed using IS-SR marker with 91 primers. [Result] Two primers ISSR-845 and ISSR-891 which ampIified two DNA bands of 510 and 300 bp respectiveIy from F1 generation and its parents were screened out from 91 primers. ISSR-845 couId distinguish the male parent from F1 hybrid and the female parent, whiIe ISSR-891 couId distinguish the female parent inbred Iine from Xiuyu 1. Seed purity test with the specific markers gave the same resuIt with fiIed trials based on morphoIogical identification. [Conclu-sion] ISSR marker is an accurate, simpIe and effective method for seed purity test bitter gourd hybrid, and thus can be used in production practices.展开更多
To compare the differences in intertranslation space of ribosomal DNA (ITS) of Melampsora larici-populina, between the isolates from China and isolates from other countries, this study investigated ITS sequences and...To compare the differences in intertranslation space of ribosomal DNA (ITS) of Melampsora larici-populina, between the isolates from China and isolates from other countries, this study investigated ITS sequences and ITS polygenetic tree based on 11 isolates that were collected from 5 races in different parts of China. The results indicated that there was no difference among the ITS sequences of 11 isolates from China. The ITS sequence of isolates from China was more homogeneous with that of isolates from Britain compared with France, Germany, and Canada. Intersimple sequence repeat (ISSR) markers were also used to study the genetic division of Melampsora larici-populina, and the results showed that the 11 tested isolates could be divided into Western population and Northern population. Genetic diversity index of race C2 was significantly different from that of races C4, C3, and C1, and no significant differences were observed among the other races. Pathogenicity division of races must not harmonize with their genetic division, except race C2. The ITS region is conservative, and ITS sequence is not fit for studying the differences that existed among the races. ISSR marker can be used for intraspecies population study, and Melampsora larici-populina in China can be divided into two populations.展开更多
Inter-simple sequence repeat (ISSR) analysis was carried out on a F2 population of 147 plants derived from a cross between a wheat male fertility restorer line 2114 and a male sterile line ND44A. Out of 43 primers exa...Inter-simple sequence repeat (ISSR) analysis was carried out on a F2 population of 147 plants derived from a cross between a wheat male fertility restorer line 2114 and a male sterile line ND44A. Out of 43 primers examined, 18 primers produced distinguishable, polymorphic bands between the two parents. Linkage analysis in the mapping population showed that two markers UBC-808 and UBC-848 were closely linked with the restorer gene Rf6 of the Triticum timopheevii CMS system. The distance between the two markers and the restorer gene was 7.9 cM and 4.9 cM, respectively. Also two parents were screened with 181 pairs of SSR primers, of which, 34.3% showed polymorphisms. But no locus was found linked with the restorer gene. Compared with the SSR technique, the ISSR approach used in the experiment provided more information and proved to be a valuable method to identify alien fragments.展开更多
[ Objective ] This study aimed to analyze the genetic diversity of turf bamboo species by using ISSR molecular marker technology. [ Method] Excellent turf bamboo species imported from France and domestic ornamental tu...[ Objective ] This study aimed to analyze the genetic diversity of turf bamboo species by using ISSR molecular marker technology. [ Method] Excellent turf bamboo species imported from France and domestic ornamental turf bamboo species were used as experimental materials for ISSR analysis, cluster analysis was conducted on 10 species of turf bamboo materials based on the obtained ISSR molectfiar ma^kers. [ Result] A total of 201 clear bands with good repeatability and high polymorphism were amplified with 21 ISSR primers, with a polymorphism rate of 93.1% ; similarity coefficients between different turf bamboo species ranged from 0.275 to 0.571, with an average similarity coefficient of 0. 357 ; according to the results of ISSR markers, 10 different ornamental turf bamboo species were di- vided into three categories by using UPGMA cluster analysis method. [Conclusion] Turf bamboo with different sources had relatively high genetic diversity, this study had provided theoretical and technical basis for the breeding, cultivation and vromotion of ornamental turf bamboo.展开更多
Objective:To characterize the genetic structure of various populations of Culex quinquefasciatus (Cx.quinquefasciatus) from India representing different geoclimatic locations.Methods:Inter simple sequence repeat(ISSR)...Objective:To characterize the genetic structure of various populations of Culex quinquefasciatus (Cx.quinquefasciatus) from India representing different geoclimatic locations.Methods:Inter simple sequence repeat(ISSR) markers were used.A set of 20 primers were screened with the laboratory populations of mosquito species.Finally the IS 40 primer was chosen based on the scorable banding pattern showing 100 percent polymorphism among the various populations.The statistical analysis was done using POPGENE 1.31 software.The consensus tree was generated based on UPGMA modified from NEIGHBOR procedure of PHYLIP Version 3.5.Results:The cluster analysis shows the main cluster which is divided into two sub cluster representing all the populations separated as per their phylogeographic and geoclimatic condition.Conclusions: The findings will be helpful in understanding the population variation under different ecological conditions and development of effective vector management strategies.展开更多
Early flowering and flower abundance have long been considered desirable traits in eucalypt breeding programs. In particular, flowers of Eucalyptus cladocalyx provide a nectar source for the production of honey in ari...Early flowering and flower abundance have long been considered desirable traits in eucalypt breeding programs. In particular, flowers of Eucalyptus cladocalyx provide a nectar source for the production of honey in arid ecosystems. To identify inter-simple sequence repeat (ISSR) markers that are associated with early flowering and flower abundance in the southern Atacama Desert, we used a sample of 47 trees, representing five Australian prove- nances of E. cladocalyx. A unified mixed linear model (which considered the effect of genetic structure and the kinship relationship among trees) revealed that three loci were significantly associated with early flowering, which accounted for 10-16 % of the phenotypic variation, while two loci accounted for 11-13 % in flowering intensity. Locus ISO1-500 bp was associated with both flowering traits. This result is consistent with our previous findings indicating that marker-assisted selection on early flowering should have significant and positive impact on flowering intensity. The application of marker-assisted selection to identify trees that flower early and intensively may increase honey production, a resource that generates additional income for the local farmers of the southern Atacama Desert.展开更多
The wild hawthorn species, Crataegus songorica K. Koch., is an important wild germplasm resource in Xinjiang, China that has been endangered in recent years. The genetic diversity of C. songorica K. Koch. germplasm in...The wild hawthorn species, Crataegus songorica K. Koch., is an important wild germplasm resource in Xinjiang, China that has been endangered in recent years. The genetic diversity of C. songorica K. Koch. germplasm in five populations from Daxigou, Xinjiang, China were evaluated based on phenotypic traits and ISSR molecular markers to provide basic infor- mation on resource protection, rational utilization and genetic improvement. The F-value for the phenotypic differentiation coefficient of the 33 traits measured ranged from 0.266 to 15.128, and mean value was 13.85%. The variation among populations was found to be lower than that within population. A total of 303 loci were detected within the five populations by 12 primers. Within 298,polymorphic loci, the polymorphism was 98.35%, showing a high genetic diversity in C. songorica K. Koch. The gene diversity within population, total population genetic diversity, genetic differentiation coefficient and gene flow were 0.2779, 0.3235, 0.1408, and 3.0511, respectively. Our results showed that C. songorica K. Koch. from Xinjiang has a high level of genetic diversity at both the phenotypic and molecular levels. Significant genetic differentiation existed within population and the differentiation trend showed a regional association. And in this study, in situ and ex situ conser- vation approaches were raised for wild hawthorn protection utilization.展开更多
We investigated the genetic variation within 32 accessions distributed to 14 species and one variety by using ISSR(inter-simple sequence repeat)markers.The results showed that genetic variation was relatively higher a...We investigated the genetic variation within 32 accessions distributed to 14 species and one variety by using ISSR(inter-simple sequence repeat)markers.The results showed that genetic variation was relatively higher among the accessions.A total of 593 bands were amplified by 12 ISSR primers,of which 535 bands(90.2%)were polymorphic.Eleven to 80 polymorphic bands were amplified from each prime,with an average of 44.6 bands.The interspecies GS(genetic similarity)value ranged from 0.430 to 0.866,and the average was 0.620.Cluster analysis showed that all accessions could be classified into 4 groups by ISSR markers.The different accessions in a species were clustered together,but they had genetic variation in molecular levels.There was obvious interspecies genetic variation.Species with similar morphological characteristics and from the same areas or neighboring geographical regions were clustered together and had close relationships.ISSR markers are useful in analyzing interspecies variation in Kengyilia.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
基金supported by ICMR-RMRC intramural fund(RMRC/IM/2022/26).
文摘Acinetobacter(A.)baumannii is a Gram-negative,non-fermenting opportunistic pathogen increasingly implicated in nosocomial infections,particularly in intensive care units(ICUs).Its ability to acquire multidrug resistance(MDR),including to carbapenems,poses a major public health threat.Infections caused by A.baumannii-ranging from pneumonia to bloodstream and wound infections-are difficult to treat and associated with high mortality,especially in critically ill patients[1].
基金Supported by Key Technology Research and Development Program for Agriculture of Jianngsu Province(BE2012323)~~
文摘Objective] This study was conducted to verify the feasibiIity of ISSR marker for identifying genetic purity of bitter gourd hybrid, and thus to provide an effective method for seed purity test in production practices. [Method] The DNA fin-gerprints of a bitter gourd cuItivar Xiuyu 1 and its parents were analyzed using IS-SR marker with 91 primers. [Result] Two primers ISSR-845 and ISSR-891 which ampIified two DNA bands of 510 and 300 bp respectiveIy from F1 generation and its parents were screened out from 91 primers. ISSR-845 couId distinguish the male parent from F1 hybrid and the female parent, whiIe ISSR-891 couId distinguish the female parent inbred Iine from Xiuyu 1. Seed purity test with the specific markers gave the same resuIt with fiIed trials based on morphoIogical identification. [Conclu-sion] ISSR marker is an accurate, simpIe and effective method for seed purity test bitter gourd hybrid, and thus can be used in production practices.
基金This paper is translated from its Chinese version in Scientia Agricultura Sinica.This study is financially supported by National Natural Science Foundation of China(30471394)Natural Science Foundation of Shaanxi Province,China(ShaanC113).
文摘To compare the differences in intertranslation space of ribosomal DNA (ITS) of Melampsora larici-populina, between the isolates from China and isolates from other countries, this study investigated ITS sequences and ITS polygenetic tree based on 11 isolates that were collected from 5 races in different parts of China. The results indicated that there was no difference among the ITS sequences of 11 isolates from China. The ITS sequence of isolates from China was more homogeneous with that of isolates from Britain compared with France, Germany, and Canada. Intersimple sequence repeat (ISSR) markers were also used to study the genetic division of Melampsora larici-populina, and the results showed that the 11 tested isolates could be divided into Western population and Northern population. Genetic diversity index of race C2 was significantly different from that of races C4, C3, and C1, and no significant differences were observed among the other races. Pathogenicity division of races must not harmonize with their genetic division, except race C2. The ITS region is conservative, and ITS sequence is not fit for studying the differences that existed among the races. ISSR marker can be used for intraspecies population study, and Melampsora larici-populina in China can be divided into two populations.
基金the National Natural Science Foundation of China(No.39893350)National High Technology Project"863"of China(No.2001AA241041).
文摘Inter-simple sequence repeat (ISSR) analysis was carried out on a F2 population of 147 plants derived from a cross between a wheat male fertility restorer line 2114 and a male sterile line ND44A. Out of 43 primers examined, 18 primers produced distinguishable, polymorphic bands between the two parents. Linkage analysis in the mapping population showed that two markers UBC-808 and UBC-848 were closely linked with the restorer gene Rf6 of the Triticum timopheevii CMS system. The distance between the two markers and the restorer gene was 7.9 cM and 4.9 cM, respectively. Also two parents were screened with 181 pairs of SSR primers, of which, 34.3% showed polymorphisms. But no locus was found linked with the restorer gene. Compared with the SSR technique, the ISSR approach used in the experiment provided more information and proved to be a valuable method to identify alien fragments.
基金Supported by National Public-benefit Research Institute Fund(CAFINT2008C12)
文摘[ Objective ] This study aimed to analyze the genetic diversity of turf bamboo species by using ISSR molecular marker technology. [ Method] Excellent turf bamboo species imported from France and domestic ornamental turf bamboo species were used as experimental materials for ISSR analysis, cluster analysis was conducted on 10 species of turf bamboo materials based on the obtained ISSR molectfiar ma^kers. [ Result] A total of 201 clear bands with good repeatability and high polymorphism were amplified with 21 ISSR primers, with a polymorphism rate of 93.1% ; similarity coefficients between different turf bamboo species ranged from 0.275 to 0.571, with an average similarity coefficient of 0. 357 ; according to the results of ISSR markers, 10 different ornamental turf bamboo species were di- vided into three categories by using UPGMA cluster analysis method. [Conclusion] Turf bamboo with different sources had relatively high genetic diversity, this study had provided theoretical and technical basis for the breeding, cultivation and vromotion of ornamental turf bamboo.
文摘Objective:To characterize the genetic structure of various populations of Culex quinquefasciatus (Cx.quinquefasciatus) from India representing different geoclimatic locations.Methods:Inter simple sequence repeat(ISSR) markers were used.A set of 20 primers were screened with the laboratory populations of mosquito species.Finally the IS 40 primer was chosen based on the scorable banding pattern showing 100 percent polymorphism among the various populations.The statistical analysis was done using POPGENE 1.31 software.The consensus tree was generated based on UPGMA modified from NEIGHBOR procedure of PHYLIP Version 3.5.Results:The cluster analysis shows the main cluster which is divided into two sub cluster representing all the populations separated as per their phylogeographic and geoclimatic condition.Conclusions: The findings will be helpful in understanding the population variation under different ecological conditions and development of effective vector management strategies.
基金supported by the Chilean National Science and Technology Research Fund(FONDECYT)projects 11090129 and 1130306
文摘Early flowering and flower abundance have long been considered desirable traits in eucalypt breeding programs. In particular, flowers of Eucalyptus cladocalyx provide a nectar source for the production of honey in arid ecosystems. To identify inter-simple sequence repeat (ISSR) markers that are associated with early flowering and flower abundance in the southern Atacama Desert, we used a sample of 47 trees, representing five Australian prove- nances of E. cladocalyx. A unified mixed linear model (which considered the effect of genetic structure and the kinship relationship among trees) revealed that three loci were significantly associated with early flowering, which accounted for 10-16 % of the phenotypic variation, while two loci accounted for 11-13 % in flowering intensity. Locus ISO1-500 bp was associated with both flowering traits. This result is consistent with our previous findings indicating that marker-assisted selection on early flowering should have significant and positive impact on flowering intensity. The application of marker-assisted selection to identify trees that flower early and intensively may increase honey production, a resource that generates additional income for the local farmers of the southern Atacama Desert.
基金supported by the Special Research Projects of National Forestry Industry of Public Benefit,China(201304701-1)the Key Discipline of Horticultural of Xinjiang Uygur Autonomous Region of China(2016-10758-3)the Key Laboratory of Characteristics of Fruit Trees Center of Xinjiang Agricultural University,China
文摘The wild hawthorn species, Crataegus songorica K. Koch., is an important wild germplasm resource in Xinjiang, China that has been endangered in recent years. The genetic diversity of C. songorica K. Koch. germplasm in five populations from Daxigou, Xinjiang, China were evaluated based on phenotypic traits and ISSR molecular markers to provide basic infor- mation on resource protection, rational utilization and genetic improvement. The F-value for the phenotypic differentiation coefficient of the 33 traits measured ranged from 0.266 to 15.128, and mean value was 13.85%. The variation among populations was found to be lower than that within population. A total of 303 loci were detected within the five populations by 12 primers. Within 298,polymorphic loci, the polymorphism was 98.35%, showing a high genetic diversity in C. songorica K. Koch. The gene diversity within population, total population genetic diversity, genetic differentiation coefficient and gene flow were 0.2779, 0.3235, 0.1408, and 3.0511, respectively. Our results showed that C. songorica K. Koch. from Xinjiang has a high level of genetic diversity at both the phenotypic and molecular levels. Significant genetic differentiation existed within population and the differentiation trend showed a regional association. And in this study, in situ and ex situ conser- vation approaches were raised for wild hawthorn protection utilization.
文摘We investigated the genetic variation within 32 accessions distributed to 14 species and one variety by using ISSR(inter-simple sequence repeat)markers.The results showed that genetic variation was relatively higher among the accessions.A total of 593 bands were amplified by 12 ISSR primers,of which 535 bands(90.2%)were polymorphic.Eleven to 80 polymorphic bands were amplified from each prime,with an average of 44.6 bands.The interspecies GS(genetic similarity)value ranged from 0.430 to 0.866,and the average was 0.620.Cluster analysis showed that all accessions could be classified into 4 groups by ISSR markers.The different accessions in a species were clustered together,but they had genetic variation in molecular levels.There was obvious interspecies genetic variation.Species with similar morphological characteristics and from the same areas or neighboring geographical regions were clustered together and had close relationships.ISSR markers are useful in analyzing interspecies variation in Kengyilia.
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.