Analysis of genetic diversity of Lactarius hatsudake in South China

2011 ◽  
Vol 57 (8) ◽  
pp. 661-666 ◽  
Author(s):  
Li He ◽  
Guo Liang ◽  
Zhou Guoying ◽  
Liu Jun-ang

Lactarius hatsudake is a type of ectomycorrhizal fungus that significantly influences the growth of pine trees. It is widely prevalent in Asian countries and has a high economic value. Artificial cultivation of this fungus has not been achieved as yet; therefore, excessive manual harvesting may cause serious damages to the site of its production. In this study, we analyzed 41 samples of L. hatsudake from south China using internal transcribed spacer (ITS) sequences. By comparing the differences among ITS sequences to identify the haplotype diversity within each population, the relationships among local populations, the relationship between the level of genetic differentiation and geographical separation, and the contributions of local and regional geographical separations to the overall ITS haplotype variation were analyzed. Genetic analysis indicates that ITS sequences obtained from these 41 L. hatsudake samples could be identified as 18 haplotypes, of which 13 haplotypes were contained in only a single sample, whereas the remaining sequence types all were contained in two or more samples. The most common sequence type, haplotype 6, was found in 16 samples and was distributed across nearly every region. The Mantel test demonstrated that there is no significant linear relationship between geographical distance and the FST value of genetic difference. Results of this research illustrates that there exists a certain degree of genetic intermixing among natural populations of L. hatsudake. From the group genetic analysis, it appears that there exists genetic differentiation of lower frequencies in natural populations of L. hatsudake; however, the linear relationship between the degree of genetic differentiation and geographical distance is not distinctly apparent.

2019 ◽  
Vol 192 (4) ◽  
pp. 744-759 ◽  
Author(s):  
Tina Wöhrmann ◽  
Ingo Michalak ◽  
Georg Zizka ◽  
Kurt Weising

Abstract The terrestrial bromeliad Fosterella rusbyi is endemic to the Bolivian Andes, where it mainly grows on steep, exposed slopes along roadsides and riverbeds in the seasonally dry tropical forest (SDTF) and the mesic montane forest (Yungas) biomes. We hypothesize that allopatric speciation may have been a main driver of diversification in Fosterella since the Miocene and that the scattered distribution of suitable habitats fostered the evolution of the high degree of endemism observed today. To provide further information relating to this hypothesis, we analysed the partition of genetic diversity and the extent of gene flow among natural populations of F. rusbyi using plastid and nuclear microsatellite markers. Nineteen plastid haplotypes were found, but the mean haplotype diversity per population was low. Nuclear microsatellite markers revealed 177 different multilocus genotypes (MLGs), of which 31 occurred in more than one plant. Recurrent MLGs were found in 76 plants that were therefore identified as clones. A considerable deficit of heterozygotes was detected at all nuclear loci. Geographical and genetic distances between populations were only weakly correlated with each other. Genetic divergence between populations was extremely high for both marker classes, suggesting that seed and pollen flow are low, even over short distances. The observed patterns are consistent with our hypothesis that newly available sites are sporadically colonized by one or a few founders, followed by in situ population expansion via vegetative propagation, self-pollination and/or biparental inbreeding, genetic differentiation among persistent populations and, ultimately, allopatric speciation.


Genetics ◽  
1982 ◽  
Vol 101 (2) ◽  
pp. 235-256
Author(s):  
Rama S Singh ◽  
Donal A Hickey ◽  
Jean David

ABSTRACT We have studied allozyme variation at 26 gene loci in nine populations of Drosophila melanogaster originating on five different continents. The distant populations show significant genetic differentiation. However, only half of the loci studied have contributed to this differentiation; the other half show identical patterns in all populations. The genetic differentiation in North American, European and African populations is correlated with the major climatic differences between north and south. These differences arise mainly from seven loci that show gene-frequency patterns suggestive of latitudinal clines in allele frequencies. The clinal variation is such that subtropical populations are more heterozygous than temperate populations. These results are discussed in relation to the selectionist and neutralist hypotheses of genetic variation in natural populations.


2007 ◽  
Vol 85 (7) ◽  
pp. 659-666 ◽  
Author(s):  
Ting-Ting Feng ◽  
Zhi-Qin Zhou ◽  
Jian-Min Tang ◽  
Ming-Hao Cheng ◽  
Shi-Liang Zhou

Malus toringoides (Rehd.) Hughes was suggested to have originated from hybridization between Malus transitoria Schneid. and Malus kansuensis Rehd., followed by repeated backcrossing to one of the putative parents. In the present study, the sequence information of the internal transcribed spacer (ITS) of nuclear ribosomal DNA (nrDNA) was used to re-examine the origin of this species. A total of 69 accessions from three natural populations (Maerkang, Xiaba and Kehe, Aba Autonomous Region, Sichuan, China) of M. toringoides and 10 accessions of its putative parents were analyzed. Using Malus angustifolia (Ait.) Michx., Malus ioensis (Wood) Britt. and Malus doumeri Chev. as outgroups, our phylogenetic analysis of the ITS sequences of M. toringoides and its putative parents showed that M. toringoides was not monophyletic, and two different types of ITS sequences which were obtained from each of the six accessions of M. toringoides were found to have clustered separately with those of the two putative parent species on the gene tree. A comparison of the sequence variation between M. toringoides and its putative parents revealed an additive variation pattern of ITS sequences in the putative hybrid species. These results are consistent with the previous morphological and amplified fragment length polymorphism (AFLP) data which suggested that M. toringoides was of hybrid origin. Our ITS data provide new molecular evidence for the hybrid origin hypothesis of M. toringoides and these results are of great importance for future study on hybridization, polyploid speciation and evolution of the genus Malus Miller.


Biologia ◽  
2015 ◽  
Vol 70 (10) ◽  
Author(s):  
Masoud Sheidai ◽  
Samira Sadeghi ◽  
Mahnaz-Arab Ameri ◽  
Ahmad-Reza Mehrabeian

AbstractThe present study aimed to reveal genetic diversity and population structure in three Onosma species i.e., Onosma bulbotrichum DC., O. elwendicum Wettst. and O. sericeum Willd. (Boraginaceae) growing in Iran. This study was performed to check if the ISSR molecular markers could be used in the Onosma species delimitation. We also investigated the infra-specific morphological variability and if we can identify infra-species taxonomic forms. The present study revealed within species genetic and morphological diversity. ISSR data could delimit the studied species as they were separated from each other in NJ tree, maximum parsimony and STRUCTURE analysis. AMOVA and Hickory tests produced significant genetic difference among the studied species. The Mantel test showed no correlation between genetic distance and geographical distance of the populations for all three species. Reticulation analysis and Nm estimation showed gene flow among these populations. We could identify a few ISSR loci that are adaptive. Data obtained can be used in conservation of these medicinal plants in Iran.


2021 ◽  
Author(s):  
Guai-qiang Chai ◽  
Yizhong Duan ◽  
Peipei Jiao ◽  
Zhongyu Du ◽  
Furen Kang

Abstract Background:Elucidating and revealing the population genetic structure, genetic diversity and recombination is essential for understanding the evolution and adaptation of species. Ammopiptanthus, which is an endangered survivor from the Tethys in the Tertiary Period, is the only evergreen broadleaf shrub grown in Northwest of China. However, little is known about its genetic diversity and underlying adaptation mechanisms. Results:Here, 111 Ammopiptanthus individuals collected from fifteen natural populations in estern China were analyzed by means of the specific locus amplified fragment sequencing (SLAF-seq). Based on the single nucleotide polymorphisms (SNPs) and insertions and deletions (InDels) detected by SLAF-seq, genetic diversity and markers associated with climate and geographical distribution variables were identified. The results of genetic diversity and genetic differentiation revealed that all fifteen populations showed medium genetic diversity, with PIC values ranging from 0.1648 to 0.3081. AMOVA and Fst indicated that a low genetic differentiation existed among populations. Phylogenetic analysis showed that NX-BG and NMG-DQH of fifteen populations have the highest homology,while the genetic structure analysis revealed that these Ammopiptanthus germplasm accessions were structured primarily along the basis of their geographic collection, and that an extensive admixture occurred in each group. In addition, the genome-wide linkage disequilibrium (LD) and principal component analysis showed that Ammopiptanthus nanus had a more diverse genomic background, and all genetic populations were clearly distinguished, although different degrees of introgression were detected in these groups. Conclusion:Our study could provide guidance to the future design of association studies and the systematic utilization and protection of the genetic variation characterizing the Ammopiptanthus.


Genetics ◽  
1978 ◽  
Vol 88 (2) ◽  
pp. 367-390
Author(s):  
Ranajit Chakraborty ◽  
Paul A Fuerst ◽  
Masatoshi Nei

ABSTRACT With the aim of testing the validity of the mutation-drift hypothesis, we examined the pattern of genetic differentiation between populations by using data from Drosophila, fishes, reptiles, and mammals. The observed relationship between genetic identity and correlation of heterozygosities of different populations or species was generally in good agreement with the theoretical expectations from the mutation-drift theory, when the variation in mutation rate among loci was taken into account. In some species of Drosophila, however, the correlation was unduly high. The relationship between the mean and variance of genetic distance was also in good agreement with the theoretical prediction in almost all organisms. We noted that both the distribution of heterozygosity within species and the pattern of genetic differentiation between species can be explained by the same set of genetic parameters in each group of organisms. Alternative hypotheses for explaining these observations are discussed.


2011 ◽  
Vol 72 (2) ◽  
pp. 115-119 ◽  
Author(s):  
Leon Mejnartowicz

Twenty-eight isozymic loci were studied in the Beskid Mts., in four populations of common silver-fir (<em>Abies alba</em>): one in Beskid Makowski (BM) and three populations in Beskid Sądecki (BS). Their genetic variation and diversity were analyzed, and Nei's genetic distances between the populations were calculated. The results show that the geographical distance between the BM population and the three BS populations is reflected in genetic distances. The BM population is clearly distinct from the others. It has the lowest genetic diversity (<em>I</em> = <em>0.42</em>), percentage of polymorphic loci <em>(%PoL </em>= <em>64.29</em>) and number of rare alleles (<em>NoRa </em>= <em>5</em>). Besides, the BM population has the highest observed heterozygosity (<em>Ho </em>= <em>0.291</em>), which exceeds the expected heterozygosity (<em>He </em>= <em>0.254</em>), estimated on the basis of the Hardy-Weinberg Principle. On the contrary, BS populations are in the state of equilibrium, which is manifested, in similar values of <em>He </em>= <em>0.262 </em>and <em>Ho </em>= <em>0.264</em>.


Hereditas ◽  
2008 ◽  
Vol 145 (2) ◽  
pp. 84-91 ◽  
Author(s):  
Lin-kai Huang ◽  
Xin-quan Zhang ◽  
Xiao Ma ◽  
Wei Liu ◽  
Fang Li ◽  
...  

2020 ◽  
Vol 11 ◽  
Author(s):  
Francisco J. Jiménez-López ◽  
Pedro L. Ortiz ◽  
María Talavera ◽  
Montserrat Arista

Flower color polymorphism, an infrequent but phylogenetically widespread condition in plants, is captivating because it can only be maintained under a few selective regimes but also because it can drive intra-morph assortative mating and promote speciation. Lysimachia arvensis is a polymorphic species with red or blue flowered morphs. In polymorphic populations, which are mostly Mediterranean, pollinators prefer blue-flowered plants to the red ones, and abiotic factors also favors blue-flowered plants. We hypothesize that the red morph is maintained in Mediterranean areas due to its selfing capacity. We assessed inbreeding depression in both color morphs in two Mediterranean populations and genetic diversity was studied via SSR microsatellites in 20 natural populations. Results showed that only 44–47% of selfed progeny of the red plants reached reproduction while about 72–91% of blue morph progeny did it. Between-morph genetic differentiation was high and the red morph had a lower genetic diversity and a higher inbreeding coefficient, mainly in the Mediterranean. Results suggest that selfing maintaining the red morph in Mediterranean areas despite its inbreeding depression. In addition, genetic differentiation between morphs suggests a low gene flow between them, suggesting reproductive isolation.


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