scholarly journals Evolution during seed production for ecological restoration? A molecular analysis of 19 species finds only minor genomic changes

2021 ◽  
Author(s):  
Malte Conrady ◽  
Christian Lampei ◽  
Oliver Bossdorf ◽  
Walter Durka ◽  
Anna Bucharova

A growing number of restoration projects require large amounts of seeds. As harvesting natural populations cannot cover the demand, wild plants are often propagated in large-scale monocultures. There are concerns that this cultivation process may cause genetic drift and unintended selection, which would alter the genetic properties of the cultivated populations and reduce their genetic diversity. Such changes could reduce the pre-existing adaptation of restored populations, and limit their adaptability to environmental change. We used single nucleotide polymorphism (SNP) markers and a pool-sequencing approach to test for genetic differentiation and changes in gene diversity during cultivation in 19 wild grassland species, comparing the source populations and up to four consecutive cultivation generations grown from these sources. We then linked the magnitudes of genetic changes to the species breeding systems and seed dormancy, to understand the roles of these traits in genetic change. The propagation of native seeds for ecosystem restoration changed the genetic composition of the cultivated generations only moderately. The genetic differentiation we observed as a consequence of cultivation was much lower than the natural genetic differentiation between different source regions, and the propagated generations harbored even higher gene diversity than wild-collected seeds. Genetic change was stronger in self-compatible species, probably as a result of increased outcrossing in the monocultures. Synthesis and applications: Our study indicates that large-scale seed production maintains the genetic integrity of natural populations. Increased genetic diversity may even increase the adaptive potential of propagated seeds, which makes them especially suitable for ecological restoration. However, we have been working with seeds from Germany and Austria, where the seed production is regulated and certified. Whether other seed production systems perform equally well remains to be tested.

2008 ◽  
Vol 88 (1) ◽  
pp. 179-186 ◽  
Author(s):  
Chu-Chuan Fan ◽  
Nicola Pecchioni ◽  
Long-Qing Chen

Calycanthus chinensis Cheng et S.Y. Chang, a tertiary relic species in China, is a shade-loving and deciduous bush withan elegant shape and beautiful flower of high ornamental value. It was widely planted in gardens and miniature scapes in China.The objective of this study was to characterize the genetic variation and structure in the three extant populations of the species, in order to provide useful information for a future conservation strategy. Twenty-two of 120 RAPD primers were selected and a total of 257 stable and clear DNA fragments were scored. Calycanthus chinensis showed a lower level of genetic diversity. At the population level, the percentage of polymorphic loci, Nei's gene diversity and Shannon’s information index were 40.9%, 0.1641 and 0.2386, respectively; while at the species level, the corresponding values were 59.1%, 0.2097 and 0.3123, respectively. The estimates of genetic differentiation based on Shannon’s information index (0.2360), Nei’s gene diversity (0.2175) and AMOVA (24.94%) were very similar, and significantly higher than the average genetic differentiation reported in outcrossed spermatophyte. So it suggested high genetic differentiation emerged among populations of C. chinensis. Genetic relationships among populations were assessed by Nei’s standard genetic distance, which suggested that the Tiantai population was genetically distinct from the other two populations. Moreover, the genetic distance was significantly correlated with geographical distance among populations (r = 0.997, t > t0.05). The gene flow (Nm) was 0.8994, indicating that gene exchange among populations was restricted. A conservation strategy was proposed based on the low gene flow and habitat deterioration, which are contributing to the endangered status of this species. Key words: Genetic diversity, endangered plant, population genetics, RAPD


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.


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.


Botany ◽  
2013 ◽  
Vol 91 (10) ◽  
pp. 653-661 ◽  
Author(s):  
Anochar Kaewwongwal ◽  
Arunee Jetsadu ◽  
Prakit Somta ◽  
Sompong Chankaew ◽  
Peerasak Srinives

The objective of this research was to determine the genetic diversity and population structure of natural populations of two rare wild species of Asian Vigna (Phaseoleae, Fabaceae), Vigna exilis Tateishi & Maxted and Vigna grandiflora (Prain) Tateishi & Maxted, from Thailand. Employing 21 simple sequence repeat markers, 107 and 85 individuals from seven and five natural populations of V. exilis and V. grandiflora, respectively, were analyzed. In total, the markers detected 196 alleles for V. exilis and 219 alleles for V. grandiflora. Vigna exilis populations showed lower average values in number of alleles, allelic richness, observed heterozygosity, gene diversity, and outcrossing rate than V. grandiflora populations, namely 58.00% versus 114.60%, 51.96% versus 74.80%, 0.02% versus 0.18%, 0.40% versus 0.66%, and 3.24% versus 17.41%, respectively. Pairwise FST among populations demonstrated that V. exilis was much more differentiated than V. grandiflora. Analysis of molecular variance revealed that 41.83% and 15.06% of total variation resided among the populations of V. exilis and V. grandiflora, respectively. Seven and two genetic clusters were detected for V. grandiflora and V. exilis by STRUCTURE analysis. Our findings suggest that different strategies are required for in situ conservation of the two species. All V. exilis populations, or as many as possible, should be conserved to protect genetic resources of this species, while a few V. grandiflora populations can capture the majority of its genetic variation.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Yuejin Zhang ◽  
Yuanyuan Chen ◽  
Ruihong Wang ◽  
Ailin Zeng ◽  
Michael K. Deyholos ◽  
...  

A large scale of EST sequences of Polyporales was screened in this investigation in order to identify EST-SSR markers for various applications. The distribution of EST sequences and SSRs in five families of Polyporales was analyzed, respectively. Mononucleotide was the most abundant type, followed by trinucleotide. Among five families, Ganodermataceae occupied the most SSR markers, followed by Coriolaceae. Functional prediction of SSR marker-containing EST sequences inGanoderma lucidumobtained three main groups, namely, cellular component, biological process, and molecular function. Thirty EST-SSR primers were designed to evaluate the genetic diversity of 13 naturalPolyporus umbellatusaccessions. Twenty one EST-SSRs were polymorphic with average PIC value of 0.33 and transferability rate of 71%. These 13P.umbellatusaccessions showed relatively high genetic diversity. The expected heterozygosity, Nei’s gene diversity, and Shannon information index were 0.41, 0.39, and 0.57, respectively. Both UPGMA dendrogram and principal coordinate analysis (PCA) showed the same cluster result that divided the 13 accessions into three or four groups.


2010 ◽  
Vol 59 (1-6) ◽  
pp. 273-285 ◽  
Author(s):  
P. O. Aikpokpodion ◽  
M. Kolesnikova-Allen ◽  
V. O. Adetimirin ◽  
M. J. Guiltinan ◽  
A. B. Eskes ◽  
...  

Abstract Inadequate knowledge of the population structure and diversity present often hamper the efficient use of germplasm collections. Using a high through-put system, twelve microsatellite loci were used to analyze genetic diversity and population structure in a national field genebank repository of 243 cacao accessions grouped into 11 populations based on their known sources. Based on multi-locus profiles, the Bayesian method was used for individual assignment to verify membership in each population, determine mislabeling and ancestry of some important accessions used in breeding program. A total of 218 alleles was revealed with a mean number of 18.2 alleles per locus. Gene diversity (He = 0.70) and allelic richness (4.34 alleles per locus) were highest in the F1 hybrid population. Differential mating system was suggested as responsible for the observed deficit and excess of heterozygotes observed among the populations. Analysis of molecular variance showed that within-population variance accounted for 63.0% of the total variance while the rest 37% was accounted for by the among-population variance. Cluster dendrogram based on UPGMA revealed two main subsets. The first group was made up of the Amelonado/Trinitario ancestry and the other of Nanay/Parinari ancestry. We found that Nanay and Parinari populations were the major source of Upper Amazon genes utilized while a large proportion of genetic diversity in the field genebank remained under-utilized in development of improved cultivars released to farmers in Nigeria. This study showed that the presence of alleles of the Upper Amazon Forasteros (Nanay, Parinari and Iquitos Mixed Calabacillo) genetic materials in the locally available accessions predated the formal large scale introduction of Upper Amazon materials in 1944. This is the first report of population structure of field genebank collections of cacao in Nigeria since more than seven decades of formal cacao breeding research.


1986 ◽  
Vol 39 (4) ◽  
pp. 369 ◽  
Author(s):  
JJ Burdon ◽  
AHD Brown

Eight Australian and two European populations of E. plantagineum were surveyed for their genetic structure at 16 variable isozyme loci. On average, the Australian and European populations possessed 2�7 and 2�6 alleles per locus, a gene diversity of 34 and 35% and heterozygosity of 32 and 29% respectively. Estimates of the outcrossing rate in one Australian population were 61 and 73% for mean single-locus and multi-locus methods respectively. The levels of genetic diversity detected in this species consistently exceed those detected in a range of other species that occupy a similar stage in succession or that have similar breeding systems. Moreover, contrary to expectation, genetic diversity was equally great in the colonial populations in Australia as in European-source populations. If this high level of isozyme diversity reflects the diversity likely to be found in other parts of the genome, attempts to achieve substantial biological control may require the use of many different control agents.


1996 ◽  
Vol 26 (8) ◽  
pp. 1454-1462 ◽  
Author(s):  
Naoki Tani ◽  
Nobuhiro Tomaru ◽  
Masayuki Araki ◽  
Kihachiro Ohba

Japanese stone pine (Pinuspumila Regel) is a dominant species characteristic of alpine zones of high mountains. Eighteen natural populations of P. pumila were studied in an effort to determine the extent and distribution of genetic diversity. The extent of genetic diversity within this species was high (HT = 0.271), and the genetic differentiation among populations was also high (GST = 0.170) compared with those of other conifers. In previous studies of P. pumila in Russia, the genetic variation within the species was also high, but the genetic differentiation among populations was low. We infer that this difference originates from differences in geographic distribution and ecological differences between the two countries. The genetic variation within each population tended, as a whole, to be smaller within marginal southern populations than within northern populations. Genetic relationships among populations reflect the geographic locations, as shown by unweighted pair-group method with arithmetic means and neighbor-joining phylogenetic trees.


2021 ◽  
Author(s):  
Rong Huang ◽  
Yinrong Liu ◽  
Jianling Chen ◽  
Zuyu Lu ◽  
Jiajia Wang ◽  
...  

Abstract Background: Angelica dahurica, belonging to the Apiaceae family, whose dry root is a famous traditional Chinese medicine named as “Bai zhi”. There are two cultivars (A. dahurica cv. ‘Hangbaizhi’ and A. dahurica cv. ‘Qibaizhi’), which have been domesticated for thousands of years. Long term artificial selection has led to great changes in root phenotypes of the two cultivars, and also decreased their adaptability to environment. We proposed hypothesis that the cultivars may lose some genetic diversity and highly differentiate from wild A. dahurica during the domestication process. However, few studies have been carried out on how domestication affects the genetic variation of this species. Here, we accessed the levels of genetic variation and differentiation within and between wild A. dahurica and its cultivars using 12 SSR markers. Results: The results revealed that the genetic diversity of the cultivars was much lower than that of wild A. dahurica, and A. dahurica cv. ‘Qibaizhi’ had lower genetic diversity compared to A. dahurica cv. ‘Hangbaizhi’. AMOVA analysis showed significant genetic differentiation between the wild and cultivated A. dahurica, and between A. dahurica cv. ‘Hangbaizhi’ and A. dahurica cv. ‘Qibaizhi’. The results of Bayesian, UPGMA, NJ and PcoA clustering analysis indicated that all 15 populations were assigned to two genetic clusters corresponding to the wild and cultivated resources. Bayesian clustering analysis further divided the cultivated resources into two sub-clusters corresponding to the two cultivars. Conclusions:Our study suggests that domestication process is likely the major factor resulting in the loss of genetic diversity in cultivated A. dahurica and significant genetic differentiation from the wild resources due to founder effect and/or artificially directional selections. This large-scale analysis of population genetics could provide valuable information for genetic resources conservation and breeding programs of Angelica dahurica.


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