Background:Numerous studies have demonstrated the existence of approximately 7,500 genetic tomato varieties worldwide.Hence,it is crucial to assess the genetic diversity among tomato cultivars.This study aimed to inve...Background:Numerous studies have demonstrated the existence of approximately 7,500 genetic tomato varieties worldwide.Hence,it is crucial to assess the genetic diversity among tomato cultivars.This study aimed to investigate the genetic diversity of selected Iranian tomato cultivars(Solanum lycopersicum)using RAPD and ISSR molecular markers.Method:Ten RAPD primers and ten ISSR primers were employed to assess the genetic diversity among 10 tomato cultivars:Matin,RFT 112,Hirad,Golsar,Raha,Hengam,Hedah,Fasa,JS12,and Emerald.Data analysis involved the UPGMA algorithm and NTYSYSpc software.Results:RAPD analysis revealed close genetic proximity between Fasa and JS12,as well as between Raha and Hadieh.Conversely,the RFT 112,Hengam,Hirad,and Emerald cultivars exhibited significant genetic diversity within this group.ISSR primer analysis identified Hengam as the most diverse variety,while Matin,Emerald,and Vibrid,as well as Raha and JS12,displayed genetic similarities with minimal observed diversity.Furthermore,the overall analysis of the cultivars using RAPD and ISSR markers indicated that Hengam exhibited the highest diversity among all the varieties.Notably,Raha and JS12 demonstrated limited diversity in this analysis.Conclusion:This research demonstrates substantial genetic diversity among the investigated tomato varieties,with Hengam displaying the highest diversity within this group.Furthermore,ISSR markers proved more effective in determining genetic diversity in tomato plants.展开更多
Jute mallow is a nutritious leafy vegetable. The leaves are rich in proteins, vitamins and essential amino acids. Molecular characterization of Jute mallow with focus on improvement of leaf yield is scarcely reported....Jute mallow is a nutritious leafy vegetable. The leaves are rich in proteins, vitamins and essential amino acids. Molecular characterization of Jute mallow with focus on improvement of leaf yield is scarcely reported. In the present study, inter sequence simple repeats (ISSR) molecular markers were employed to assess genetic diversity and relationships of 83 accessions of Jute mallow from different parts of Africa and Asia conserved at the World Vegetable Center East and Southern Africa. A total of 89 bands were amplified by 8 ISSR primers. Number of polymorphic bands per primer ranged from 2 to 6 with an average of 2.75 bands per primer. Polymorphic information content (PIC) values ranged from 0.390 to 0.760 with average of 0.53. Average Nei’s gene diversity (h) and Shannon’s information index (I) were 0.335 and 0.494 respectively. The highest pairwise genetic distance was 0.431 observed in a population from East Africa accessions. PC1 and PC2 axis explained 21.69% and 11.66% of the total variation respectively. UPGMA cluster analysis grouped the accessions into six main clusters at genetic similarity coefficient of 0.53 as standard value for classification. These results have important implications for jute mallow breeding and conservation.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
Abstract Inter-simple sequence repeat (ISSR) markers were used to determine the genetic variation and genetic differentiation of cultured and wild populations of Trachidermus fasciatus, an endangered catadromous fis...Abstract Inter-simple sequence repeat (ISSR) markers were used to determine the genetic variation and genetic differentiation of cultured and wild populations of Trachidermus fasciatus, an endangered catadromous fish species in China. Six selected primers were used to amplify DNA samples from 85 individuals, and 353 loci were detected. Relatively low genetic diversity was detected in the cultured population (the percentage of polymorphic loci PPL=73.80%, Nei's gene diversity h--0.178 2, Shannon information index I=0.276 9). However, the genetic diversity at the species level was relatively high (PPL-91.78%; h = 0.258 3, I= 0.398 6). The UPGMA tree grouped together the genotypes almost according to their cultured and wild origin, showing distinct differences in genetic structure between wild and cultured populations. The pairwise F^t values confirmed significant genetic differentiation between wild and cultured samples. The cultivated population seems to be low in genetic diversity as a result of detrimental genetic effects in the captive population. The results suggest that ISSR markers are effective for rapid assessment of the degree of diversity of a population, thus giving important topical information relevant to preserving endangered species.展开更多
Assessment of genetic diversity is an essential component in germplasm characterization and conservation.There are three wild rice species in Hainan Province,including Oryza rufipogon Griff.In order to detect the gene...Assessment of genetic diversity is an essential component in germplasm characterization and conservation.There are three wild rice species in Hainan Province,including Oryza rufipogon Griff.In order to detect the genetic diversity of different populations of Oryza rufipogon in Hainan,ISSR(inter-simple sequence repeat)and SSR(simple sequence repeat)markers were used to investigate 180 accessions from six localities in Hainan.Fourteen ISSR primers amplified 185 alleles with 171(92.43%)polymorphic,the number of alleles ranged from 8 to 17,with an average of 13.14 alleles per locus.Thirty-eight pairs of SSR primers used in this study amplified 213 alleles with 190(89.20%)polymorphic,the number of alleles ranged from 2 to 14,with an average of 5.66 alleles per locus.Both ISSR and SSR analyses revealed a high level of genetic diversity in the wild populations.The population with the highest genetic diversity is Wanning(WN),and the population with lowest genetic diversity is Wenchang(WC).The results of a UPGMA cluster using the NTSYS program showed that each population has a low degree of genetic differentiation.Furthermore,the Mantel test revealed that the genetic similarities detected by ISSR and SSR were significantly correlated(r=0.8634,t=93.67)when detecting genetic diversity at the species level.The two molecular marker systems were able to determine the genetic diversity among Oryza rufipogon,and the two groups of indexes obtained by using the two markers have a high level of consistency.展开更多
A total of 206 SSR (Simple Sequence Repeats) primer pairs were used to detect genetic diversity in 52 accessions of three unique wheat varieties of western China. A total of 488, 472, and 308 allelic variants were d...A total of 206 SSR (Simple Sequence Repeats) primer pairs were used to detect genetic diversity in 52 accessions of three unique wheat varieties of western China. A total of 488, 472, and 308 allelic variants were detected in 31 Yunnan, 15 Tibetan and 6 Xinjiang wheat accessions with an average of PIC values 0.2764, 0.3082, and 0.1944, respectively. Substantial differences in allelic polymorphisms were detected by SSR markers in all the 21 chromosomes, the 7 homoeologous groups, and the three genomes (A, B, and D) in Yunnan, Tibetan, and Xinjiang wheat. The highest and lowest allelic polymorphisms in all the 21 chromosomes were observed in 3B and 1D chromosomes, respectively. The lowest and highest allelic polymorphisms among the seven homoeologous groups was observed in 6 and 3 homoeologous groups, respectively. Among the three genomes, B genome showed the highest, A the intermediate, and D the lowest allelic polymorphism. The genetic distance (GD) indexes within Yunnan, Tibetan, and Xinjiang wheat, and between different wheat types were calculated. The GD value was found to be much higher within Yunnan and Tibetan wheat than within Xinjiang wheat, but the GD value between Yunnan and Tibetan wheat was lower than those between Yunnan and Xinjiang wheat, and between Tibetan and Xinjiang wheat. The cluster analysis indicated a closer relationship between Yunnan and Tibetan wheat than that between Yunnan and Xinjiang wheat or between Tibetan and Xinjiang wheat.展开更多
[Objective] This study was to reveal the genetic diversity and genetic relationship of the kenaf(Hibiscus cannabinus L.) resources from different origins, thus providing basis for genetic improvement and molecular mar...[Objective] This study was to reveal the genetic diversity and genetic relationship of the kenaf(Hibiscus cannabinus L.) resources from different origins, thus providing basis for genetic improvement and molecular marker-assisted breeding of kenaf. [Method] Ninety one ISSR molecular markers were used for amplification on 44 shares of kenaf germplasm resources, of which 21 showing good diversity and clear bands were chosen for PCR amplification. Based on amplification results, the genetic similarity coefficients among kenaf germplasm resources were calculated by using analytic software NTSYSpc-2.10e, and phylogenetic tree was then established via UPGMA. [Result] Totally 169 bands were amplified using the 21 screened primers, averagely 8.05 bands were amplified from each primer. Of them, 141 bands were polymorphic, accounting for 83.4%. When genetic similarity coefficient 0.887 was used as criterion L1, these 44 shares of kenaf germplasm could be classified to be 32 shares of cultivars and 12 shares of wild type or half-wild type varieties. When genetic similarity coefficient 0.897 was used as criterion L2, these 32 shares of cultivars could be further grouped into four sub-clusters. The genetic diversities between cultivars and wild type or half-wild type varieties were between 0.46-0.91, showing huge hereditary difference; while that among 32 cultivars were between 0.85-0.97, suggesting that genetic relationships among cultivars are relatively close and their genetic similarities are rather narrow. [Conclusion] ISSR could well determine the genetic similarities among kenaf germplasm resources and provide valuable molecular information for selecting parents of hybrid cross, which can lay a good foundation for DNA mapping of kenaf germplasm resources.展开更多
Lepidium sativum(commonly known as garden cress) belongs to the family Brassicaceae. It is a fastgrowing erect, annual herbaceous plant. Its seeds possess significant fracture healing, anti-asthmatic, anti-diabetic,...Lepidium sativum(commonly known as garden cress) belongs to the family Brassicaceae. It is a fastgrowing erect, annual herbaceous plant. Its seeds possess significant fracture healing, anti-asthmatic, anti-diabetic,hypoglycemic, nephrocurative and nephroprotective activities. In the present study, we assessed the genetic diversity of various genotypes of L. sativum using inter-simple sequence repeat(ISSR) markers. Out of 41 ISSR primers screened, 32 primers showed significant, clear and reproducible bands. A total of 510 amplified bands were obtained using 32 ISSR primers, out of which 422 bands were polymorphic and 88 bands were monomorphic. The percentage of polymorphism was found to be 82. A total of 35 unique alleles ranging insize from 200 to 2,900 bp were observed.Cluster analysis based on unweighted pair-group method,arithmetic mean divided the 18 genotypes into two main clusters, with the first having only HCS-08 genotype of L.sativum and other having all of the other 17 genotypes. The Jaccard similarity coefficient revealed a broad range32–72 % genetic relatedness among the 18 genotypes.展开更多
Analysis of differentiation (genetic diversity and related relationships) among 22 landrace (Ficus carica L. sativa) and 2 wild form (F. carica L. caprificus) accessions of fig growing under the same environmental con...Analysis of differentiation (genetic diversity and related relationships) among 22 landrace (Ficus carica L. sativa) and 2 wild form (F. carica L. caprificus) accessions of fig growing under the same environmental conditions in the Palestinian Fig Collection, Til, Nablus, Palestine, using PCR-based Random Amplified Polymorphic DNA (RAPD) and pomological markers, revealed considerable genetic diversity. The phenotypic analysis shows that pomological traits were permitted to evaluate morphological variability of fig landraces. The Jaccard similarity coefficient between landraces was determined by cluster analysis using the UPGMA method. Based on the genetic relationships among genotypes as illustrated by the dendrograms, generated from pomological and RAPD data by UPGMA clustering method, the following 12 genotypes: Qaisi, Mwazi, Barqawi, Inaqi, Swadi, Kharobi, Hmadibiadi, Sfari, Khdari, Biadi, Qrawi, and Slati, may be considered as distinct landraces. The remaining genotypes may be considered as synonymous (4) (Hmadi and Hmari, and Ajloni and Adloni), or closely related (6) landraces (Zraqi and Ghzali, Blati and Neami, and Qraee and Khurtmani). The wild fig forms clustered together and may be considered as distinct genotypes. Clustering patterns obtained from the combined (pomological and RAPD) markers had higher discriminatory power to discriminate fig landraces than using either pomological or RAPD markers alone. These results proved the importance of both pomological and RAPD markers to elucidate in part denomination problems and relationships among cultivars. Wide phenotypic and molecular diversity found in fig germplasm indicates a considerable potential for improving this crop.展开更多
Microsatellite markers have been increasingly used in genetic studies on fishery species because of their high applicability in selective breeding programs. Here we reported the development of microsatellite markers a...Microsatellite markers have been increasingly used in genetic studies on fishery species because of their high applicability in selective breeding programs. Here we reported the development of microsatellite markers and their utilization in mud carp (Cirrhina molitorella). An (CA)15 enriched library has been constructed for mud carp, using the magnetic beads enrichment procedure. Sequence analysis of 60 randomly picked positive colonies indicate that 56 (93.3%) of the colonies contain microsatellites. Microsatellite polymorphism was assessed using 10 mud carp individuals, and 12 microsatellite loci turned out to be polymorphic. We utilized these loci to study the genetic diversity of a wild population (WM) and a cultured population (CM) of the mud carp. A total of 109 alleles were detected with an average of 9.08 alleles per locus. The mean value of the observed heterozygosity of WM and CM was 0.6361 and 0.6417, respectively, and significant decrease of genetic diversity in CM was not observed. The genetic distance between the two populations was 0.1546 and the value of Gsr was 0.0473. This showed that there existed a slight genetic differentiation between WM and CM.展开更多
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
Omphalogramma souliei Franch. is an endangered perennial herb only distributed in alpine areas of SW China. ISSR markers were applied to determine the genetic variation and genetic structure of 60 individuals of three...Omphalogramma souliei Franch. is an endangered perennial herb only distributed in alpine areas of SW China. ISSR markers were applied to determine the genetic variation and genetic structure of 60 individuals of three populations of O. souliei in NW Yunnan, China. The genetic diversity at the species level is low with P=42.5% (percentage of polymorphic bands) and Hsp=0.1762 (total genetic diversity). However, a high level of genetic differentiation among populations was detected based on different measures (Nei's genetic diversity analysis: Gst=0.6038; AMOVA analysis: Fst=0.6797). Low level of genetic diversity within populations and significant genetic differentiation among populations might be due to the mixed mating system in which xenogamy predominated and autogamy played an assistant role in O. souliei. The genetic drift due to small population size and limited current gene flow also resulted in significant genetic differentiation. The assessment of genetic variation and differentiation of the endangered species provides important information for conservation on a genetic basis. Conservation strategies for this rare endemic species are proposed.展开更多
The present study was conducted to assess the molecular characterization and genetic diversity amongst natural populations of Myrica rubra in Guangxi Zhuang Autonomous Region, China, thus to provide scientific evidenc...The present study was conducted to assess the molecular characterization and genetic diversity amongst natural populations of Myrica rubra in Guangxi Zhuang Autonomous Region, China, thus to provide scientific evidence for germplasm conservation and exploitation. Using ISSR (inter-simple sequence repeats) markers, the level of genetic variation and the molecular characterization of 10 natural populations of M. rubra, originated from Guangxi Zhuang Autonomous Region in China, were performed. Based on 11 primers, 123 clear and reproducible DNA fragments were generated, of which 95 (77.24%) were polymorphic. The average value of Nei's gene diversity (He) was 0.268. The coefficient of genetic differentiation (Gst) was 0.341, revealing that 34.1% of the total molecular variance existed among populations. The Mantel statistical testing showed that the genetic distance was correlated to the geographic distance, but the correlation was not significant. Ten populations were divided into two big clusters according to unweighted pair group method with arithmetic mean (UPGMA) analysis. One consisted of populations of Rongxian (RX), Hepu (HP), Liangqing (LQ), Marshan (MS), Lingshan (LS) and Shansi (SS), which originated from the southern Guangxi, while the other was composed of Guanyang (GY) and Lingui (LG) populations of northern Guangxi, Huanjiang (HJ) populations of northwestern Guangxi and Shanglin (SL) populations of southern Guangxi. The level of genetic variation in wild M. rubra population distributed in Guangxi is high. Gene drift within the population was responsible for genetic variation in wild M. rubra in Guangxi, and the effect of the genetic flow among inter-populations was not significant. Classification of wild M. rubra populations was correlated to climate and environment. The molecular characterization and diversity assessment of M. rubra is of immense value for planning conservation of its genetic resources and their exploitation for further studies.展开更多
To investigate the relationship between genetic distance (GD) and hybrid performance, two types of molecular markers, microsatellites (simple sequence repeats, SSRs) and intro-simple sequence repeats (ISSRs), were emp...To investigate the relationship between genetic distance (GD) and hybrid performance, two types of molecular markers, microsatellites (simple sequence repeats, SSRs) and intro-simple sequence repeats (ISSRs), were employed to detect the genetic diversity of 3 double low self-incompatible lines and 22 male parental varieties of Brassica napus from different geographical origins. Hybrids were produced in a NCⅡ mating design by hand-pollination. The result indicated that 25 parental varieties (lines) could be divided into six groups by Un-weighted Pair Group Mathematics Average (UPGMA) clustering based on GDs. SI-1300 and SI-1320 could be singly clustered into one group, respectively. Varieties from China could be separated into another group, SI-1310 and varieties from foreign countries could be separated into other three groups. The grouping was generally consistent with parental pedigrees and geographical origins. Significant differences in yield, quality and phenological period traits were observed among these parent groups. Although hybrid yield/plant showed significantly positive correlation with genetic distance based on SSR and ISSR markers, but the determination coefficient was low. It appeared to be unsuitable for using the genetic distance based on SSR and ISSR markers to predict heterosis and hybrid performance in Brassica napus.展开更多
The AFLP (amplified fragrnent length polymorphism)technique was used to analyse the genetic diversity in four scallop species, Patinopecten yessoensis, A rgopecten irradians, Chlamys nobilis and C. farreri. The gene...The AFLP (amplified fragrnent length polymorphism)technique was used to analyse the genetic diversity in four scallop species, Patinopecten yessoensis, A rgopecten irradians, Chlamys nobilis and C. farreri. The genetic similarity indexes of these four species are 0.8415, 0.7863, 0.7190 and 0.6731, while Shannon diversity indexes are 43.52, 58.87, 80.16 and 92.83, respectively. As analyzed, the genetic diversities in two native species, i.e., C, farreri and C. nobilis, are higher than those in other two introduced species, A. irradians and P. yessoensis. The results also showed that C. nobilis and C, farreri shared the most common loci. The genetic distance indicated that C. nobilis and C. farreri are closely related. Moreover, out of 510 AFLP markers, 21 specific bands are found to distinguish the four species scallops and these markers may be applied to the specific germplasm characterization and molecular assistant classification in scallops.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
Tree peony has nine wild species,but the evolutionary relationship of them is still unclear.Here,a total of 274 specimens from 22 natural populations of nine wild species were collected,and their genetic diversity and...Tree peony has nine wild species,but the evolutionary relationship of them is still unclear.Here,a total of 274 specimens from 22 natural populations of nine wild species were collected,and their genetic diversity and similarity was analyzed based on Simple Sequence Repeats(SSR)molecular markers.A total of 106 alleles were generated based on 20 primers and with an average of 5.3 alleles per primer.Shannon’s information index(I)ranged from 0.6333 to 1.7842,and the average of Nei’s genetic diversity coefficient(H)was 0.5771.Polymorphism Information Content(PIC)value varied from 0.29 to 0.77,ten of these primers had high polymorphism(PIC≥0.50).All the above genetic parameters of primers reflect more rich genetic diversity information compared with other researches using SSR molecular markers to study the genetic diversity of tree peony wild species.At the population level,the lowest and highest degree of genetic diversity occurred in Paeonia ludlowii-P1 and P.delavayi-P3 population,respectively.Whereas at species level,the genetic diversity of 9 wild peony species was as follows:P.lutea>P.delavayi>P.rockii>P.qiui>P.ostii>P.decomposita>P.potaninii>P.spontanea>P.ludlowii.Furthermore,cluster analysis at species level divided the nine wild tree peony species into two branches.In branch I,the closest phylogenetic relationship was found between P.ostii and P.rockii,followed by P.spontanea,P.qiui,and P.decomposita.In branch II,the closest relationship occurred between P.lutea and P.delavayi,followed by P.potaninii and P.ludlowii.Clustering results supported the division of tree peonies into two subsects(Delavayanae and Vaginatae),it also supported P.potaninii and P.ludlowii as independent species.The results provided novel insight into the genetic diversity and phylogenetic relationship of nine wild tree peony species.It will help formulate comprehensive protection measures of wild germplasm resources and select proper parents for distant hybridization in the future.展开更多
Garlic(Allium sativum),an asexually propagated vegetable and medicinal crop,has abundant genetic variation.Genetic diversity evaluation based on molecular markers has apparent advantages since their genomic abundance,...Garlic(Allium sativum),an asexually propagated vegetable and medicinal crop,has abundant genetic variation.Genetic diversity evaluation based on molecular markers has apparent advantages since their genomic abundance,environment insensitivity,and non-tissue specific features.However,the limited number of available DNA markers,especially SSR markers,are insufficient to conduct related genetic diversity assessment studies in garlic.In this study,4372 EST-SSR markers were newly developed,and 12 polymorphic markers together with other 17 garlic SSR markers were used to assess the genetic diversity and population structure of 127 garlic accessions.The averaged polymorphism information content(PIC)of these 29 SSR markers was 0.36,ranging from 0.22 to 0.49.Seventy-nine polymorphic loci were detected among these accessions,with an average of 3.48 polymorphic loci per SSR.Both the clustering analyses based on either the genotype data of SSR markers or the phenotypic data of morphological traits obtained genetic distance divided the 127 garlic accessions into three clusters.Moreover,the Mantel test showed that genetic distance had no significant correlations with geographic distance,and weak correlations were found between genetic distance and the phenotypic traits.AMOVA analysis showed that the main genetic variation of this garlic germplasm collection existed in the within-population or cluster.Results of this study will be of great value for the genetic/breeding studies in garlic and enhance the utilization of these garlic germplasms.展开更多
Genetic diversity of 62 Sichuan wheat landraces accessions of China was investigated by agronomic traits and SSR markers. The landrace population showed the characters of higher tiller capability and more kernels/spik...Genetic diversity of 62 Sichuan wheat landraces accessions of China was investigated by agronomic traits and SSR markers. The landrace population showed the characters of higher tiller capability and more kernels/spike, especially tiller no./plant of six accessions was over 40 and kernels/spike of three accessions was more than 70. A total of 547 alleles in 124 polymorphic loci were detected with an average of 4.76 alleles per locus by 114 SSR markers. Parameters analysis indicated that the genetic diversity ranked as genome A 〉 genome B 〉 genome D, and the homoeologous groups ranked as 5〉4〉3〉1〉2〉7〉6 based on genetic richness (Ri). Furthermore, chromosomes 2A, 1B and 3D had more diversity than that of chromosomes 4A, 7A and 6B. The variation of SSR loci on chromosomes 1B, 2A, 2D, 3B, and 4B implied that, in the past, different selective pressures might have acted on different chromosome regions of these landraces. Our results suggested that Sichuan common wheat landraces is a useful genetic resource for genetic research and wheat improvement.展开更多
14 yellow-seeded rapeseed lines (Brassia napus L.) from different genetic sources were used to analyze diversity of testa pigments content, oil and protein content, and RAPD markers. The results showed that the anthoc...14 yellow-seeded rapeseed lines (Brassia napus L.) from different genetic sources were used to analyze diversity of testa pigments content, oil and protein content, and RAPD markers. The results showed that the anthocyanin and melanin were the most important pigments in testa and their content were responsible for the variation in seed color ranging from orange to black yellow, 14 yellow-seeded lines could be classified into 3 groups: high anthocyanin content group with anthocyanin content over 2. 54 mg g-1 DW, the seed color was light yellow or orange; low pigments content group with low content of anthocyanin and melanin, the testa was transparent and the seed color was light yellow, greenish yellow or twany; high melanin content group with melanin content over 178. 4U(A290nm) , the testa was black, the seed color was black yellow. Oil content changed from 36.2% to 45. 5%, protein content from 21.1% to 27.7% , and the correlation analysis revealed that the oil content is highly significantly negatively correlated with the protein content. The cluster analysis showed that the extensive genetic variation existed among 14 yellow-seeded lines by using unweighted paired group method with arithmetic average (UPGMA) based on RAPD markers which were amplified with decamer primers, the genetic similarity among them ranged from 0. 25 to 0.909, and 14 yellow-seeded lines could put into 2 clusters corresponding to genome difference.展开更多
文摘Background:Numerous studies have demonstrated the existence of approximately 7,500 genetic tomato varieties worldwide.Hence,it is crucial to assess the genetic diversity among tomato cultivars.This study aimed to investigate the genetic diversity of selected Iranian tomato cultivars(Solanum lycopersicum)using RAPD and ISSR molecular markers.Method:Ten RAPD primers and ten ISSR primers were employed to assess the genetic diversity among 10 tomato cultivars:Matin,RFT 112,Hirad,Golsar,Raha,Hengam,Hedah,Fasa,JS12,and Emerald.Data analysis involved the UPGMA algorithm and NTYSYSpc software.Results:RAPD analysis revealed close genetic proximity between Fasa and JS12,as well as between Raha and Hadieh.Conversely,the RFT 112,Hengam,Hirad,and Emerald cultivars exhibited significant genetic diversity within this group.ISSR primer analysis identified Hengam as the most diverse variety,while Matin,Emerald,and Vibrid,as well as Raha and JS12,displayed genetic similarities with minimal observed diversity.Furthermore,the overall analysis of the cultivars using RAPD and ISSR markers indicated that Hengam exhibited the highest diversity among all the varieties.Notably,Raha and JS12 demonstrated limited diversity in this analysis.Conclusion:This research demonstrates substantial genetic diversity among the investigated tomato varieties,with Hengam displaying the highest diversity within this group.Furthermore,ISSR markers proved more effective in determining genetic diversity in tomato plants.
文摘Jute mallow is a nutritious leafy vegetable. The leaves are rich in proteins, vitamins and essential amino acids. Molecular characterization of Jute mallow with focus on improvement of leaf yield is scarcely reported. In the present study, inter sequence simple repeats (ISSR) molecular markers were employed to assess genetic diversity and relationships of 83 accessions of Jute mallow from different parts of Africa and Asia conserved at the World Vegetable Center East and Southern Africa. A total of 89 bands were amplified by 8 ISSR primers. Number of polymorphic bands per primer ranged from 2 to 6 with an average of 2.75 bands per primer. Polymorphic information content (PIC) values ranged from 0.390 to 0.760 with average of 0.53. Average Nei’s gene diversity (h) and Shannon’s information index (I) were 0.335 and 0.494 respectively. The highest pairwise genetic distance was 0.431 observed in a population from East Africa accessions. PC1 and PC2 axis explained 21.69% and 11.66% of the total variation respectively. UPGMA cluster analysis grouped the accessions into six main clusters at genetic similarity coefficient of 0.53 as standard value for classification. These results have important implications for jute mallow breeding and conservation.
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.
基金Supported by the Key Laboratory of Freshwater Biodiversity Conservation and Utilization, Ministry of Agriculture (No. LFBCU0713)the Special Research Foundation for Public Welfare Marine Program (No. 200905019-2)
文摘Abstract Inter-simple sequence repeat (ISSR) markers were used to determine the genetic variation and genetic differentiation of cultured and wild populations of Trachidermus fasciatus, an endangered catadromous fish species in China. Six selected primers were used to amplify DNA samples from 85 individuals, and 353 loci were detected. Relatively low genetic diversity was detected in the cultured population (the percentage of polymorphic loci PPL=73.80%, Nei's gene diversity h--0.178 2, Shannon information index I=0.276 9). However, the genetic diversity at the species level was relatively high (PPL-91.78%; h = 0.258 3, I= 0.398 6). The UPGMA tree grouped together the genotypes almost according to their cultured and wild origin, showing distinct differences in genetic structure between wild and cultured populations. The pairwise F^t values confirmed significant genetic differentiation between wild and cultured samples. The cultivated population seems to be low in genetic diversity as a result of detrimental genetic effects in the captive population. The results suggest that ISSR markers are effective for rapid assessment of the degree of diversity of a population, thus giving important topical information relevant to preserving endangered species.
文摘Assessment of genetic diversity is an essential component in germplasm characterization and conservation.There are three wild rice species in Hainan Province,including Oryza rufipogon Griff.In order to detect the genetic diversity of different populations of Oryza rufipogon in Hainan,ISSR(inter-simple sequence repeat)and SSR(simple sequence repeat)markers were used to investigate 180 accessions from six localities in Hainan.Fourteen ISSR primers amplified 185 alleles with 171(92.43%)polymorphic,the number of alleles ranged from 8 to 17,with an average of 13.14 alleles per locus.Thirty-eight pairs of SSR primers used in this study amplified 213 alleles with 190(89.20%)polymorphic,the number of alleles ranged from 2 to 14,with an average of 5.66 alleles per locus.Both ISSR and SSR analyses revealed a high level of genetic diversity in the wild populations.The population with the highest genetic diversity is Wanning(WN),and the population with lowest genetic diversity is Wenchang(WC).The results of a UPGMA cluster using the NTSYS program showed that each population has a low degree of genetic differentiation.Furthermore,the Mantel test revealed that the genetic similarities detected by ISSR and SSR were significantly correlated(r=0.8634,t=93.67)when detecting genetic diversity at the species level.The two molecular marker systems were able to determine the genetic diversity among Oryza rufipogon,and the two groups of indexes obtained by using the two markers have a high level of consistency.
基金Hi-Tech Research and Development (863) Program of China (No. 2006AA10Z1F6)Hi-Tech Re-search of Jiangsu Province (No.BG2005310)+2 种基金the Program for Changjiang Scholars and Innovative Research Team in University (No.10418) (PCSIRT)Innovation Foundation of Young Science and Technology of Nanjing Agriculture UniversityIntroduction of Talents Foundation of Nanjing Agriculture University.
文摘A total of 206 SSR (Simple Sequence Repeats) primer pairs were used to detect genetic diversity in 52 accessions of three unique wheat varieties of western China. A total of 488, 472, and 308 allelic variants were detected in 31 Yunnan, 15 Tibetan and 6 Xinjiang wheat accessions with an average of PIC values 0.2764, 0.3082, and 0.1944, respectively. Substantial differences in allelic polymorphisms were detected by SSR markers in all the 21 chromosomes, the 7 homoeologous groups, and the three genomes (A, B, and D) in Yunnan, Tibetan, and Xinjiang wheat. The highest and lowest allelic polymorphisms in all the 21 chromosomes were observed in 3B and 1D chromosomes, respectively. The lowest and highest allelic polymorphisms among the seven homoeologous groups was observed in 6 and 3 homoeologous groups, respectively. Among the three genomes, B genome showed the highest, A the intermediate, and D the lowest allelic polymorphism. The genetic distance (GD) indexes within Yunnan, Tibetan, and Xinjiang wheat, and between different wheat types were calculated. The GD value was found to be much higher within Yunnan and Tibetan wheat than within Xinjiang wheat, but the GD value between Yunnan and Tibetan wheat was lower than those between Yunnan and Xinjiang wheat, and between Tibetan and Xinjiang wheat. The cluster analysis indicated a closer relationship between Yunnan and Tibetan wheat than that between Yunnan and Xinjiang wheat or between Tibetan and Xinjiang wheat.
基金Supported by The National High Technology Research and Development Program of China(2001AA241211)Industry Special:Studyon the Efficient Production and Harvest Technique in Ramee, Flax,Jute/Kenaf(NYHYJX07-18)~~
文摘[Objective] This study was to reveal the genetic diversity and genetic relationship of the kenaf(Hibiscus cannabinus L.) resources from different origins, thus providing basis for genetic improvement and molecular marker-assisted breeding of kenaf. [Method] Ninety one ISSR molecular markers were used for amplification on 44 shares of kenaf germplasm resources, of which 21 showing good diversity and clear bands were chosen for PCR amplification. Based on amplification results, the genetic similarity coefficients among kenaf germplasm resources were calculated by using analytic software NTSYSpc-2.10e, and phylogenetic tree was then established via UPGMA. [Result] Totally 169 bands were amplified using the 21 screened primers, averagely 8.05 bands were amplified from each primer. Of them, 141 bands were polymorphic, accounting for 83.4%. When genetic similarity coefficient 0.887 was used as criterion L1, these 44 shares of kenaf germplasm could be classified to be 32 shares of cultivars and 12 shares of wild type or half-wild type varieties. When genetic similarity coefficient 0.897 was used as criterion L2, these 32 shares of cultivars could be further grouped into four sub-clusters. The genetic diversities between cultivars and wild type or half-wild type varieties were between 0.46-0.91, showing huge hereditary difference; while that among 32 cultivars were between 0.85-0.97, suggesting that genetic relationships among cultivars are relatively close and their genetic similarities are rather narrow. [Conclusion] ISSR could well determine the genetic similarities among kenaf germplasm resources and provide valuable molecular information for selecting parents of hybrid cross, which can lay a good foundation for DNA mapping of kenaf germplasm resources.
文摘Lepidium sativum(commonly known as garden cress) belongs to the family Brassicaceae. It is a fastgrowing erect, annual herbaceous plant. Its seeds possess significant fracture healing, anti-asthmatic, anti-diabetic,hypoglycemic, nephrocurative and nephroprotective activities. In the present study, we assessed the genetic diversity of various genotypes of L. sativum using inter-simple sequence repeat(ISSR) markers. Out of 41 ISSR primers screened, 32 primers showed significant, clear and reproducible bands. A total of 510 amplified bands were obtained using 32 ISSR primers, out of which 422 bands were polymorphic and 88 bands were monomorphic. The percentage of polymorphism was found to be 82. A total of 35 unique alleles ranging insize from 200 to 2,900 bp were observed.Cluster analysis based on unweighted pair-group method,arithmetic mean divided the 18 genotypes into two main clusters, with the first having only HCS-08 genotype of L.sativum and other having all of the other 17 genotypes. The Jaccard similarity coefficient revealed a broad range32–72 % genetic relatedness among the 18 genotypes.
文摘Analysis of differentiation (genetic diversity and related relationships) among 22 landrace (Ficus carica L. sativa) and 2 wild form (F. carica L. caprificus) accessions of fig growing under the same environmental conditions in the Palestinian Fig Collection, Til, Nablus, Palestine, using PCR-based Random Amplified Polymorphic DNA (RAPD) and pomological markers, revealed considerable genetic diversity. The phenotypic analysis shows that pomological traits were permitted to evaluate morphological variability of fig landraces. The Jaccard similarity coefficient between landraces was determined by cluster analysis using the UPGMA method. Based on the genetic relationships among genotypes as illustrated by the dendrograms, generated from pomological and RAPD data by UPGMA clustering method, the following 12 genotypes: Qaisi, Mwazi, Barqawi, Inaqi, Swadi, Kharobi, Hmadibiadi, Sfari, Khdari, Biadi, Qrawi, and Slati, may be considered as distinct landraces. The remaining genotypes may be considered as synonymous (4) (Hmadi and Hmari, and Ajloni and Adloni), or closely related (6) landraces (Zraqi and Ghzali, Blati and Neami, and Qraee and Khurtmani). The wild fig forms clustered together and may be considered as distinct genotypes. Clustering patterns obtained from the combined (pomological and RAPD) markers had higher discriminatory power to discriminate fig landraces than using either pomological or RAPD markers alone. These results proved the importance of both pomological and RAPD markers to elucidate in part denomination problems and relationships among cultivars. Wide phenotypic and molecular diversity found in fig germplasm indicates a considerable potential for improving this crop.
文摘Microsatellite markers have been increasingly used in genetic studies on fishery species because of their high applicability in selective breeding programs. Here we reported the development of microsatellite markers and their utilization in mud carp (Cirrhina molitorella). An (CA)15 enriched library has been constructed for mud carp, using the magnetic beads enrichment procedure. Sequence analysis of 60 randomly picked positive colonies indicate that 56 (93.3%) of the colonies contain microsatellites. Microsatellite polymorphism was assessed using 10 mud carp individuals, and 12 microsatellite loci turned out to be polymorphic. We utilized these loci to study the genetic diversity of a wild population (WM) and a cultured population (CM) of the mud carp. A total of 109 alleles were detected with an average of 9.08 alleles per locus. The mean value of the observed heterozygosity of WM and CM was 0.6361 and 0.6417, respectively, and significant decrease of genetic diversity in CM was not observed. The genetic distance between the two populations was 0.1546 and the value of Gsr was 0.0473. This showed that there existed a slight genetic differentiation between WM and CM.
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.
基金supported by the National Basic Research Program of China (973 program,Grant No.2007CB411600)the Yunnan Provincial Natural Science Foundation (Grant No.2005C0051M)the National Natural Science Foundation of China (Grant No.30571137).
文摘Omphalogramma souliei Franch. is an endangered perennial herb only distributed in alpine areas of SW China. ISSR markers were applied to determine the genetic variation and genetic structure of 60 individuals of three populations of O. souliei in NW Yunnan, China. The genetic diversity at the species level is low with P=42.5% (percentage of polymorphic bands) and Hsp=0.1762 (total genetic diversity). However, a high level of genetic differentiation among populations was detected based on different measures (Nei's genetic diversity analysis: Gst=0.6038; AMOVA analysis: Fst=0.6797). Low level of genetic diversity within populations and significant genetic differentiation among populations might be due to the mixed mating system in which xenogamy predominated and autogamy played an assistant role in O. souliei. The genetic drift due to small population size and limited current gene flow also resulted in significant genetic differentiation. The assessment of genetic variation and differentiation of the endangered species provides important information for conservation on a genetic basis. Conservation strategies for this rare endemic species are proposed.
基金supported by the National Natural Science Foundation of China (30560007)
文摘The present study was conducted to assess the molecular characterization and genetic diversity amongst natural populations of Myrica rubra in Guangxi Zhuang Autonomous Region, China, thus to provide scientific evidence for germplasm conservation and exploitation. Using ISSR (inter-simple sequence repeats) markers, the level of genetic variation and the molecular characterization of 10 natural populations of M. rubra, originated from Guangxi Zhuang Autonomous Region in China, were performed. Based on 11 primers, 123 clear and reproducible DNA fragments were generated, of which 95 (77.24%) were polymorphic. The average value of Nei's gene diversity (He) was 0.268. The coefficient of genetic differentiation (Gst) was 0.341, revealing that 34.1% of the total molecular variance existed among populations. The Mantel statistical testing showed that the genetic distance was correlated to the geographic distance, but the correlation was not significant. Ten populations were divided into two big clusters according to unweighted pair group method with arithmetic mean (UPGMA) analysis. One consisted of populations of Rongxian (RX), Hepu (HP), Liangqing (LQ), Marshan (MS), Lingshan (LS) and Shansi (SS), which originated from the southern Guangxi, while the other was composed of Guanyang (GY) and Lingui (LG) populations of northern Guangxi, Huanjiang (HJ) populations of northwestern Guangxi and Shanglin (SL) populations of southern Guangxi. The level of genetic variation in wild M. rubra population distributed in Guangxi is high. Gene drift within the population was responsible for genetic variation in wild M. rubra in Guangxi, and the effect of the genetic flow among inter-populations was not significant. Classification of wild M. rubra populations was correlated to climate and environment. The molecular characterization and diversity assessment of M. rubra is of immense value for planning conservation of its genetic resources and their exploitation for further studies.
文摘To investigate the relationship between genetic distance (GD) and hybrid performance, two types of molecular markers, microsatellites (simple sequence repeats, SSRs) and intro-simple sequence repeats (ISSRs), were employed to detect the genetic diversity of 3 double low self-incompatible lines and 22 male parental varieties of Brassica napus from different geographical origins. Hybrids were produced in a NCⅡ mating design by hand-pollination. The result indicated that 25 parental varieties (lines) could be divided into six groups by Un-weighted Pair Group Mathematics Average (UPGMA) clustering based on GDs. SI-1300 and SI-1320 could be singly clustered into one group, respectively. Varieties from China could be separated into another group, SI-1310 and varieties from foreign countries could be separated into other three groups. The grouping was generally consistent with parental pedigrees and geographical origins. Significant differences in yield, quality and phenological period traits were observed among these parent groups. Although hybrid yield/plant showed significantly positive correlation with genetic distance based on SSR and ISSR markers, but the determination coefficient was low. It appeared to be unsuitable for using the genetic distance based on SSR and ISSR markers to predict heterosis and hybrid performance in Brassica napus.
基金This work was financially supported by the National High-tech“863”Project of China under contract Nos 2003AA603022 and 2002AA6210the Shandong Excellent Middle-age and Young Scientist Foundation Project under contract No.01BS10)
文摘The AFLP (amplified fragrnent length polymorphism)technique was used to analyse the genetic diversity in four scallop species, Patinopecten yessoensis, A rgopecten irradians, Chlamys nobilis and C. farreri. The genetic similarity indexes of these four species are 0.8415, 0.7863, 0.7190 and 0.6731, while Shannon diversity indexes are 43.52, 58.87, 80.16 and 92.83, respectively. As analyzed, the genetic diversities in two native species, i.e., C, farreri and C. nobilis, are higher than those in other two introduced species, A. irradians and P. yessoensis. The results also showed that C. nobilis and C, farreri shared the most common loci. The genetic distance indicated that C. nobilis and C. farreri are closely related. Moreover, out of 510 AFLP markers, 21 specific bands are found to distinguish the four species scallops and these markers may be applied to the specific germplasm characterization and molecular assistant classification in scallops.
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.
基金National Key R&D Program of China(Grant No.2019YFD1001500)National Natural Science Foundation of China(Grant No.31972440)China Agriculture Research System(Grant No.CARS-21)。
文摘Tree peony has nine wild species,but the evolutionary relationship of them is still unclear.Here,a total of 274 specimens from 22 natural populations of nine wild species were collected,and their genetic diversity and similarity was analyzed based on Simple Sequence Repeats(SSR)molecular markers.A total of 106 alleles were generated based on 20 primers and with an average of 5.3 alleles per primer.Shannon’s information index(I)ranged from 0.6333 to 1.7842,and the average of Nei’s genetic diversity coefficient(H)was 0.5771.Polymorphism Information Content(PIC)value varied from 0.29 to 0.77,ten of these primers had high polymorphism(PIC≥0.50).All the above genetic parameters of primers reflect more rich genetic diversity information compared with other researches using SSR molecular markers to study the genetic diversity of tree peony wild species.At the population level,the lowest and highest degree of genetic diversity occurred in Paeonia ludlowii-P1 and P.delavayi-P3 population,respectively.Whereas at species level,the genetic diversity of 9 wild peony species was as follows:P.lutea>P.delavayi>P.rockii>P.qiui>P.ostii>P.decomposita>P.potaninii>P.spontanea>P.ludlowii.Furthermore,cluster analysis at species level divided the nine wild tree peony species into two branches.In branch I,the closest phylogenetic relationship was found between P.ostii and P.rockii,followed by P.spontanea,P.qiui,and P.decomposita.In branch II,the closest relationship occurred between P.lutea and P.delavayi,followed by P.potaninii and P.ludlowii.Clustering results supported the division of tree peonies into two subsects(Delavayanae and Vaginatae),it also supported P.potaninii and P.ludlowii as independent species.The results provided novel insight into the genetic diversity and phylogenetic relationship of nine wild tree peony species.It will help formulate comprehensive protection measures of wild germplasm resources and select proper parents for distant hybridization in the future.
基金supported by the Education Development Fund of Northwest A&F University (2017) to Z.Chengthe Chinese Universities Scientific Fund (2452019017) to Y.Pan
文摘Garlic(Allium sativum),an asexually propagated vegetable and medicinal crop,has abundant genetic variation.Genetic diversity evaluation based on molecular markers has apparent advantages since their genomic abundance,environment insensitivity,and non-tissue specific features.However,the limited number of available DNA markers,especially SSR markers,are insufficient to conduct related genetic diversity assessment studies in garlic.In this study,4372 EST-SSR markers were newly developed,and 12 polymorphic markers together with other 17 garlic SSR markers were used to assess the genetic diversity and population structure of 127 garlic accessions.The averaged polymorphism information content(PIC)of these 29 SSR markers was 0.36,ranging from 0.22 to 0.49.Seventy-nine polymorphic loci were detected among these accessions,with an average of 3.48 polymorphic loci per SSR.Both the clustering analyses based on either the genotype data of SSR markers or the phenotypic data of morphological traits obtained genetic distance divided the 127 garlic accessions into three clusters.Moreover,the Mantel test showed that genetic distance had no significant correlations with geographic distance,and weak correlations were found between genetic distance and the phenotypic traits.AMOVA analysis showed that the main genetic variation of this garlic germplasm collection existed in the within-population or cluster.Results of this study will be of great value for the genetic/breeding studies in garlic and enhance the utilization of these garlic germplasms.
基金supported by the National Basic Research Program of China (2011CB100100)the Program for Scientific Innovative Research Team in Sichuan, China(2011JTD0015 and 11TD005)
文摘Genetic diversity of 62 Sichuan wheat landraces accessions of China was investigated by agronomic traits and SSR markers. The landrace population showed the characters of higher tiller capability and more kernels/spike, especially tiller no./plant of six accessions was over 40 and kernels/spike of three accessions was more than 70. A total of 547 alleles in 124 polymorphic loci were detected with an average of 4.76 alleles per locus by 114 SSR markers. Parameters analysis indicated that the genetic diversity ranked as genome A 〉 genome B 〉 genome D, and the homoeologous groups ranked as 5〉4〉3〉1〉2〉7〉6 based on genetic richness (Ri). Furthermore, chromosomes 2A, 1B and 3D had more diversity than that of chromosomes 4A, 7A and 6B. The variation of SSR loci on chromosomes 1B, 2A, 2D, 3B, and 4B implied that, in the past, different selective pressures might have acted on different chromosome regions of these landraces. Our results suggested that Sichuan common wheat landraces is a useful genetic resource for genetic research and wheat improvement.
文摘14 yellow-seeded rapeseed lines (Brassia napus L.) from different genetic sources were used to analyze diversity of testa pigments content, oil and protein content, and RAPD markers. The results showed that the anthocyanin and melanin were the most important pigments in testa and their content were responsible for the variation in seed color ranging from orange to black yellow, 14 yellow-seeded lines could be classified into 3 groups: high anthocyanin content group with anthocyanin content over 2. 54 mg g-1 DW, the seed color was light yellow or orange; low pigments content group with low content of anthocyanin and melanin, the testa was transparent and the seed color was light yellow, greenish yellow or twany; high melanin content group with melanin content over 178. 4U(A290nm) , the testa was black, the seed color was black yellow. Oil content changed from 36.2% to 45. 5%, protein content from 21.1% to 27.7% , and the correlation analysis revealed that the oil content is highly significantly negatively correlated with the protein content. The cluster analysis showed that the extensive genetic variation existed among 14 yellow-seeded lines by using unweighted paired group method with arithmetic average (UPGMA) based on RAPD markers which were amplified with decamer primers, the genetic similarity among them ranged from 0. 25 to 0.909, and 14 yellow-seeded lines could put into 2 clusters corresponding to genome difference.