The genetic diversity and population structure of the Dybowski＇s frog（Rana dybowskii） were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser K...The genetic diversity and population structure of the Dybowski＇s frog（Rana dybowskii） were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser Khingan Mountains and Changbai Mountains,China.Results showed that allele number of the 11 microsatellite loci was in the range of 2-10 in all populations,with the mean of 5.6.The average expected heterozygosity（HE） was 0.572,indicating a moderate polymorphism.The results of genetic differentiation coefficient（FST） showed that population genetic differentiation was significant between Changbai and Lesser Khingan Mountains（p〈0.001）.This result was verified further by Nei＇s genetic distance（DA） based on UPGMA phy-logenetic trees and by AMOVA analysis.In conclusion,the populations distributed in Lesser Khingan Mountains and Changbai Mountain are proposed to be two distinct management units（MUs） for their protection and management.展开更多
Robinia pseudoacacia is an important afforesta-tion tree introduced to China in 1878.In the present study,we examined the genetic diversity among 687 strains rep-resenting four improved varieties and two secondary pro...Robinia pseudoacacia is an important afforesta-tion tree introduced to China in 1878.In the present study,we examined the genetic diversity among 687 strains rep-resenting four improved varieties and two secondary prov-enances,comprising 641 clones and 46 seedlings.Ninety-one simple sequence repeats(SSRs)were selected through segregation analysis and polymorphism characterization,and all sampled individuals were genotyped using well-characterized SSR markers.After excluding loci with non-neutral equilibrium,missing locus data and null alleles,we used 36 primer pairs to assess the genetic diversity of these germplasm resources,revealing vast genetic differentiation among the samples,with an average of 8.352 alleles per locus and a mean Shannon′s index of 1.302.At the popula-tion level,the partitioning of variability was assessed using analysis of molecular variance,which revealed 93%and 7%variation within and among collection sites,respectively.Four clusters were detected using structure analysis,indi-cating a degree of genetic differentiation among the six populations.Insights into the genetic diversity and structure of R.pseudoacacia provide a theoretical basis for the con-servation,breeding and sustainable development in China.展开更多
Salix L.(willow)is the largest genus of the family Salicaceae and plays an important role in riparian habitats,wetlands and in shrub tundra.Due to the diff erent implications for the species belonging to this family,i...Salix L.(willow)is the largest genus of the family Salicaceae and plays an important role in riparian habitats,wetlands and in shrub tundra.Due to the diff erent implications for the species belonging to this family,it is fundamental to identify molecular tools characterizing relevant clones.A set of six multilocus and multiallelic simple sequence repeat(SSRs)markers are presented,leading to 390 polymorphic fragments considered as single dominant markers and able to discriminate successfully 92 S.alba L.from 24 Salix spp.The polymorphic fragments have been used to perform genetic diversity studies,and to investigate population structures and cluster analysis in a germplasm collection.The results highlight the capability of the six SSRs to be powerful genetic resources in applied forestry research,both to distinguish S.alba clones from Salix spp.and to perform genetic population studies for breeding programs.展开更多
Population density,species richness and critical population parameters are crucial in determining the levels of gene diversity in dioecious species of the genus Calamus.The extent of intraspecific and intrageneric gen...Population density,species richness and critical population parameters are crucial in determining the levels of gene diversity in dioecious species of the genus Calamus.The extent of intraspecific and intrageneric genetic variability in Calamus from the southern Western Ghats of India was studied using 26 microsatellite markers by sampling 227 individuals belonging to seven economically important species.The heterozygosity of microsatellite loci ranged from zero to 0.78.Average gene diversity within species was 0.13;in all species it was 0.18 and amongst species was 0.06.The Shannon Information Index was the lowest for Calamus metzianus(0.11),whereas it ranged from 0.16 to 0.26 for other species.The expected heterozygosity varied from 0.08 to 0.18.Calamus hookerianus and Calamu travancoricus showed the highest genetic differentiation(44%)revealed through Fst values,whereas the lowest(22%)was observed between Calamus gamblei and Calamu thwaitesii.Population structuring and phylogenetic analysis differentiated the seven species.Due to overexploitation and loss of rare alleles,small populations could lead to fertilization between closely related individuals,resulting in inbreeding and increasing the risk of extinction.This could be important for species such as C.metzianus where allelic polymorphism was 23%,whereas for all other species it was 38%to 46%.Genetic diversity“micro-hotspots”were identified from the protected area network of the southern and central Western Ghats with highest observed heterozygosity.Four microhotspots from the Agasthyamalai Biosphere Reserve and the Pushpagiri Wildlife Sanctuary may be possible for long-term conservation programs.The findings of this study lay a strong foundation for strengthening protected area networks,especially areas with intermediate levels of disturbance.展开更多
Growth traits and genetic diversity of 23 provenances of Quercus rubra introduced from North America were analyzed in a provenance trial established with a randomized block design in Hwaseong,Gyeonggi,South Korea in 1...Growth traits and genetic diversity of 23 provenances of Quercus rubra introduced from North America were analyzed in a provenance trial established with a randomized block design in Hwaseong,Gyeonggi,South Korea in 1993.Growth variables and survival at age 25 were compared with results from early stages.Height,DBH,volume and stem straightness of Q.rubra was better than those of the domestic oak(Quercus accutissima).Growth of the Dunham Island provenance from New York was the best among the 23 provenances that of the Eagle River provenance from Wisconsin was poorest.Survival rate at age25 was on average 52%.The longitude of seed origin and growth of provenance were consistently significantly negatively correlated at all ages.Growth of coastal provenances was superior to that of the inland provenances,which were separated by the Appalachian Mountains.Genetic diversity and genetic distance among the provenances were evaluated using micro satellite markers.The allelic frequencies showed high polymorphism in 10 microsatellite loci,and 292 alleles were found.Of 10 loci,two were commonly found in the 23 provenances.The mean allelic diversity and heterozygosity observed among the provenances were similar to those from the native populations of Q.rubra in North America.Nei’s genetic distance among the 23 was estimated and showed that a clear trend between geographic and genetic distances,indicating that some provenances have high genetic diversity with superior growth performance.展开更多
Forest management may have significant effects on forest connectivity and natural population sizes.Harvesting old-growth single trees may also change natural patterns of genetic variation and spatial genetic structure...Forest management may have significant effects on forest connectivity and natural population sizes.Harvesting old-growth single trees may also change natural patterns of genetic variation and spatial genetic structure.This study evaluated the impacts of forest management using a silvicultural system of seed trees on the genetic diversity and spatial genetic structure of Eremanthus erythropappus(DC.)MacLeish.A complete survey of 275 trees on four plots was undertaken out to compare the genetic variation of a managed stand with an unmanaged stand.We genotyped all adult and juvenile individuals 60 months after the management and compared the genetic diversity and the spatial genetic structure parameters.Genetic diversity was considered high because of an efficient gene flow between stands.There were no genetic differences between stands and no evidence of inbreeding.Genetic clustering identified a single population(K=1),indicating no genetic differentiation between managed and unmanaged stands.Adult and juvenile individuals of the unmanaged stand were more geographically structured than individuals from the managed one.There was a tendency of coancestry among juveniles at the first class of distance of the managed stand,suggesting a drift of genetic structure possibly caused by management.Understanding early responses to management on genetic diversity and stand structure is a first step to ensuring the effectiveness of conservation practices of tree species.The sustainability of forest management of E.erythropappus on genetic diversity,and more accurately,on spatial genetic structure needs evaluation over time to promote effective conservation of the population size and genetic variability.展开更多
Patterns of gene flow and gene introgres sion can be used to assess the risk of genetic pollution of wild forest trees from widespread cultivated trees.A comprehensive understanding of the genetic relationships and le...Patterns of gene flow and gene introgres sion can be used to assess the risk of genetic pollution of wild forest trees from widespread cultivated trees.A comprehensive understanding of the genetic relationships and levels of gene flow among wild and cultivated common walnut(Juglans regia)has become an urgent issue.Using twelve microsatellite markers,we investigated the genetic diversity and gene flow between cultivated and wild trees of J.regia in the Qinling Mountains,China.A high level of genetic variation was detected in both cultivated and wild trees.The mean number of alleles per locus was 17.5.Observed heterozygosity(HO)and expected heterozygosity(HE)were 0.777 and 0.800,respectively.Pollination of mother trees was not by nearest neighbors,and a paternity of 60.7%of offspring evaluated could not be assigned to a local,sampled tree.Pollen flow from cultivated trees to wild trees was infrequent(5.4%),and selfing rates ranged from zero to 25.0%.Male parents were located from 0 to 1005 m from their female partners,with an average pollination distance of 285.1 m.These results are discussed in light of the cultivated species’diversity,outlining the frequent spontaneous genetic contributions from the wild to the cultivated compartment.In addition,the pollen flow parameters provide useful information about the dynamics of pollen movement within J.regia populations.展开更多
Two Chinese domestic yak populations representing the Plateau type and the Huanhu Alpine type were analysed with 12 bovine microsatellite primers.All primer pairs functioned in the yak genome and polymorphism was foun...Two Chinese domestic yak populations representing the Plateau type and the Huanhu Alpine type were analysed with 12 bovine microsatellite primers.All primer pairs functioned in the yak genome and polymorphism was found at all loci.The allele size ranges and frequencies of the two yak populations were similar and there was considerable overlap with the allele size ranges observed in cattle.Data for European cattle breeds was obtained from the Cattle Diversity Database(CaDBase)to interpret the heterozygosity and genetic distance estimates in yak populations.Heterozygosity estimated for the two yak populations was comparable to that of European cattle while Nei's Genetic Distance DA between the two yak populations was less than distances between the most closely related German cattle breeds.Bovine microsatellite primers proved to be a valuable tool for characterization of yak populations.展开更多
文摘The genetic diversity and population structure of the Dybowski＇s frog（Rana dybowskii） were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser Khingan Mountains and Changbai Mountains,China.Results showed that allele number of the 11 microsatellite loci was in the range of 2-10 in all populations,with the mean of 5.6.The average expected heterozygosity（HE） was 0.572,indicating a moderate polymorphism.The results of genetic differentiation coefficient（FST） showed that population genetic differentiation was significant between Changbai and Lesser Khingan Mountains（p〈0.001）.This result was verified further by Nei＇s genetic distance（DA） based on UPGMA phy-logenetic trees and by AMOVA analysis.In conclusion,the populations distributed in Lesser Khingan Mountains and Changbai Mountain are proposed to be two distinct management units（MUs） for their protection and management.
基金This work was supported by the Doctoral Scientific Research Starting Foundation of Henan University of Science and Technology(13480089)National Nature Science Foundation of China(31570677)+1 种基金the National Key R&D Program of China(2017YFD0600503)the National Forestry and Grassland Administration of Science and Technology Development Center Project(2016007).
文摘Robinia pseudoacacia is an important afforesta-tion tree introduced to China in 1878.In the present study,we examined the genetic diversity among 687 strains rep-resenting four improved varieties and two secondary prov-enances,comprising 641 clones and 46 seedlings.Ninety-one simple sequence repeats(SSRs)were selected through segregation analysis and polymorphism characterization,and all sampled individuals were genotyped using well-characterized SSR markers.After excluding loci with non-neutral equilibrium,missing locus data and null alleles,we used 36 primer pairs to assess the genetic diversity of these germplasm resources,revealing vast genetic differentiation among the samples,with an average of 8.352 alleles per locus and a mean Shannon′s index of 1.302.At the popula-tion level,the partitioning of variability was assessed using analysis of molecular variance,which revealed 93%and 7%variation within and among collection sites,respectively.Four clusters were detected using structure analysis,indi-cating a degree of genetic differentiation among the six populations.Insights into the genetic diversity and structure of R.pseudoacacia provide a theoretical basis for the con-servation,breeding and sustainable development in China.
基金the Project“RGV-FAO”(The Italian Ministry of Agricultural,Food and Forestry Policies-MiPAAF D.M.18862/06).
文摘Salix L.(willow)is the largest genus of the family Salicaceae and plays an important role in riparian habitats,wetlands and in shrub tundra.Due to the diff erent implications for the species belonging to this family,it is fundamental to identify molecular tools characterizing relevant clones.A set of six multilocus and multiallelic simple sequence repeat(SSRs)markers are presented,leading to 390 polymorphic fragments considered as single dominant markers and able to discriminate successfully 92 S.alba L.from 24 Salix spp.The polymorphic fragments have been used to perform genetic diversity studies,and to investigate population structures and cluster analysis in a germplasm collection.The results highlight the capability of the six SSRs to be powerful genetic resources in applied forestry research,both to distinguish S.alba clones from Salix spp.and to perform genetic population studies for breeding programs.
基金The work was supported by the Department of Biotechnology,Government of India(Order No.BT/156/NE/TBP/2011)the Kerala State Council for Science,Technology and Environment(KSCSTE),Thiruvananthapuram(Order No.234/KBC/2012/KSCSTE).
文摘Population density,species richness and critical population parameters are crucial in determining the levels of gene diversity in dioecious species of the genus Calamus.The extent of intraspecific and intrageneric genetic variability in Calamus from the southern Western Ghats of India was studied using 26 microsatellite markers by sampling 227 individuals belonging to seven economically important species.The heterozygosity of microsatellite loci ranged from zero to 0.78.Average gene diversity within species was 0.13;in all species it was 0.18 and amongst species was 0.06.The Shannon Information Index was the lowest for Calamus metzianus(0.11),whereas it ranged from 0.16 to 0.26 for other species.The expected heterozygosity varied from 0.08 to 0.18.Calamus hookerianus and Calamu travancoricus showed the highest genetic differentiation(44%)revealed through Fst values,whereas the lowest(22%)was observed between Calamus gamblei and Calamu thwaitesii.Population structuring and phylogenetic analysis differentiated the seven species.Due to overexploitation and loss of rare alleles,small populations could lead to fertilization between closely related individuals,resulting in inbreeding and increasing the risk of extinction.This could be important for species such as C.metzianus where allelic polymorphism was 23%,whereas for all other species it was 38%to 46%.Genetic diversity“micro-hotspots”were identified from the protected area network of the southern and central Western Ghats with highest observed heterozygosity.Four microhotspots from the Agasthyamalai Biosphere Reserve and the Pushpagiri Wildlife Sanctuary may be possible for long-term conservation programs.The findings of this study lay a strong foundation for strengthening protected area networks,especially areas with intermediate levels of disturbance.
基金supported by a research project(No.FTIS 2014109B0-1820-AA01)of Korea Forest Service and the Seoul National University Carbon Sink Graduate Program provided by Korea Forest Service&Korea Forestry Promotion Institute。
文摘Growth traits and genetic diversity of 23 provenances of Quercus rubra introduced from North America were analyzed in a provenance trial established with a randomized block design in Hwaseong,Gyeonggi,South Korea in 1993.Growth variables and survival at age 25 were compared with results from early stages.Height,DBH,volume and stem straightness of Q.rubra was better than those of the domestic oak(Quercus accutissima).Growth of the Dunham Island provenance from New York was the best among the 23 provenances that of the Eagle River provenance from Wisconsin was poorest.Survival rate at age25 was on average 52%.The longitude of seed origin and growth of provenance were consistently significantly negatively correlated at all ages.Growth of coastal provenances was superior to that of the inland provenances,which were separated by the Appalachian Mountains.Genetic diversity and genetic distance among the provenances were evaluated using micro satellite markers.The allelic frequencies showed high polymorphism in 10 microsatellite loci,and 292 alleles were found.Of 10 loci,two were commonly found in the 23 provenances.The mean allelic diversity and heterozygosity observed among the provenances were similar to those from the native populations of Q.rubra in North America.Nei’s genetic distance among the 23 was estimated and showed that a clear trend between geographic and genetic distances,indicating that some provenances have high genetic diversity with superior growth performance.
基金supported by the Fundacao de Amparo a Pesquisa do Estado de Minas Gerais (FAPEMIG)[CRA APQ-02641-14]in part by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior-Brasil(CAPES)-Finance Code 001。
文摘Forest management may have significant effects on forest connectivity and natural population sizes.Harvesting old-growth single trees may also change natural patterns of genetic variation and spatial genetic structure.This study evaluated the impacts of forest management using a silvicultural system of seed trees on the genetic diversity and spatial genetic structure of Eremanthus erythropappus(DC.)MacLeish.A complete survey of 275 trees on four plots was undertaken out to compare the genetic variation of a managed stand with an unmanaged stand.We genotyped all adult and juvenile individuals 60 months after the management and compared the genetic diversity and the spatial genetic structure parameters.Genetic diversity was considered high because of an efficient gene flow between stands.There were no genetic differences between stands and no evidence of inbreeding.Genetic clustering identified a single population(K=1),indicating no genetic differentiation between managed and unmanaged stands.Adult and juvenile individuals of the unmanaged stand were more geographically structured than individuals from the managed one.There was a tendency of coancestry among juveniles at the first class of distance of the managed stand,suggesting a drift of genetic structure possibly caused by management.Understanding early responses to management on genetic diversity and stand structure is a first step to ensuring the effectiveness of conservation practices of tree species.The sustainability of forest management of E.erythropappus on genetic diversity,and more accurately,on spatial genetic structure needs evaluation over time to promote effective conservation of the population size and genetic variability.
基金supported by Qinling National Forest Ecosystem Research StationNational Natural Science Foundation of China(Nos.31200500,41471038,and 32070372)+2 种基金Shaanxi Academy of Science Research Funding Project(Y19Z604F12)Natural Science Foundation of Shaanxi Province of China(2019JM-008)the public health specialty in the department of traditional Chinese Medicine(2017-66,2018-43,2019-68)。
文摘Patterns of gene flow and gene introgres sion can be used to assess the risk of genetic pollution of wild forest trees from widespread cultivated trees.A comprehensive understanding of the genetic relationships and levels of gene flow among wild and cultivated common walnut(Juglans regia)has become an urgent issue.Using twelve microsatellite markers,we investigated the genetic diversity and gene flow between cultivated and wild trees of J.regia in the Qinling Mountains,China.A high level of genetic variation was detected in both cultivated and wild trees.The mean number of alleles per locus was 17.5.Observed heterozygosity(HO)and expected heterozygosity(HE)were 0.777 and 0.800,respectively.Pollination of mother trees was not by nearest neighbors,and a paternity of 60.7%of offspring evaluated could not be assigned to a local,sampled tree.Pollen flow from cultivated trees to wild trees was infrequent(5.4%),and selfing rates ranged from zero to 25.0%.Male parents were located from 0 to 1005 m from their female partners,with an average pollination distance of 285.1 m.These results are discussed in light of the cultivated species’diversity,outlining the frequent spontaneous genetic contributions from the wild to the cultivated compartment.In addition,the pollen flow parameters provide useful information about the dynamics of pollen movement within J.regia populations.
文摘Two Chinese domestic yak populations representing the Plateau type and the Huanhu Alpine type were analysed with 12 bovine microsatellite primers.All primer pairs functioned in the yak genome and polymorphism was found at all loci.The allele size ranges and frequencies of the two yak populations were similar and there was considerable overlap with the allele size ranges observed in cattle.Data for European cattle breeds was obtained from the Cattle Diversity Database(CaDBase)to interpret the heterozygosity and genetic distance estimates in yak populations.Heterozygosity estimated for the two yak populations was comparable to that of European cattle while Nei's Genetic Distance DA between the two yak populations was less than distances between the most closely related German cattle breeds.Bovine microsatellite primers proved to be a valuable tool for characterization of yak populations.
