Genetic variability and structure of Gomortega keule (Molina) Baillon (Gomortegaceae) relict populations: geographical and genetic fragmentation and its implications for conservation

Gomortega keule (Molina) Baillon is a rare Chilean species classified as endangered and currently under conservation. Currently, conservation of this species is carried out by private companies and government agencies, but is done so based more on pragmatic criteria than scientifically based strategies. In this context, information concerning the genetic variability of the species among the different populations over its entire distribution range is incomplete, making it difficult to coordinate management and conservation strategies. Here we report a study to evaluate the genetic variability and population structure of G. keule over its entire distribution in Chile. Twenty-five ISSR primers for 223 individuals from 11 geographical populations were tested to evaluate genetic variability. Results showed a high level of genetic diversity for the species. A high level of genetic differentiation among populations was found, while genetic structure of the geographic populations was also shown by using STRUCTURE 2.1 software. Despite the fact that this species has been highly affected by human intervention and habitat destruction, a high level of genetic diversity was present. A likely explanation for this is that it reflects the previous distribution of this long-lived species and the current lack of sexual regeneration. Genetic diversity data must be considered in the development of a management strategy for further developing the protected areas, for identifying isolated small populations for conservation, and using larger populations with higher genetic diversity as seed sources for ex situ propagation and replanting.

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Genetic diversity and outcrossing rate of Dipterocarpus dyeri in Ma Da lowland tropical forest (Dong Nai)

Vietnam Journal of Biotechnology ◽

10.15625/1811-4989/16/3/12111 ◽

2018 ◽

Vol 16 (3) ◽

pp. 431-437

Author(s):

Nguyen Minh Duc ◽

Nguyen Minh Tam ◽

Vu Dinh Duy ◽

Bui Thi Tuyet Xuan ◽

Dang Phan Hien ◽

...

Keyword(s):

Genetic Diversity ◽

Tropical Forests ◽

Habitat Destruction ◽

Conservation Strategy ◽

Ex Situ ◽

Conservation Strategies ◽

Mixed Mating ◽

Forest Patches ◽

Lowland Tropical Forest ◽

Mating Rate

Human activities often lead to the disturbed and fragmented habitat and consequently threated species. Dipterocarpus dyeri (Dipterocarpaceae) is widely distributed in lowland rainforests in southeast Vietnam. Due to over- exploitation and habitat destruction in the 1980s and 1990s, the species is listed as threatened. Understanding the genetic variation and mating rate within D. dyeri population that occurs in forest patches is necessary to establish effectively conservation strategies for this species. To conserve the species in tropical forests, genetic diversity and mating rate were investigated on the basis of eight microsatellites (single sequence repeat, SSR). All of the eight loci were polymorphic. A total of 33 different alleles were observed across the screened loci. The SSR data indicated high genetic diversities (NA = 4.1; HO = 0.461 and HE = 0.543) and the inbreeding value was high (0.185). The mating system parameters were determined using the mixed mating model and indicated high outcrossing rates (tm = 0.884 and ts = 0.645). The differences of significant tm - ts value indicated that inbreeding contributed to selfing rate for this species in lowland tropical forests of Ma Da. This study also indicated the importance of conserving the genetic resources of Dipterocarpus dyeri species in Ma Da rainforests. Genetic conservation should derive from correlated outcrossing. The conservation strategy should be established an ex-situ conservation site with new big population for this species from all genetic groups, which might improve its fitness under different environmental stresses.

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Assessment of genetic variability amongst cultivated populations of Khasi mandarin (Citrus reticulata Blanco) detected by ISSR

Plant Genetic Resources ◽

10.1017/s1479262121000162 ◽

2021 ◽

pp. 1-11

Author(s):

Karishma Kashyap ◽

Rasika M. Bhagwat ◽

Sofia Banu

Keyword(s):

Genetic Diversity ◽

Genetic Variability ◽

Inter Simple Sequence Repeat ◽

Northeast India ◽

Issr Markers ◽

Citrus Reticulata ◽

Brahmaputra Valley ◽

Indian Food ◽

Cultivated Populations ◽

High Level

Abstract Khasi mandarin (Citrus reticulata Blanco) is a commercial mandarin variety grown in northeast India and one of the 175 Indian food items included in the global first food atlas. The cultivated plantations of Khasi mandarin grown prominently in the lower Brahmaputra valley of Assam, northeast India, have been genetically eroded. The lack in the efforts for conservation of genetic variability in this mandarin variety prompted diversity analysis of Khasi mandarin germplasm across the region. Thus, the study aimed to investigate genetic diversity and partitioning of the genetic variations within and among 92 populations of Khasi mandarin collected from 10 cultivated sites in Kamrup and Kamrup (M) districts of Assam, India, using Inter-Simple Sequence Repeat (ISSR) markers. The amplification of genomic DNA with 17 ISSR primers yielded 216 scorable DNA amplicons of which 177 (81.94%) were polymorphic. The average polymorphism information content was 0.39 per primer. The total genetic diversity (HT = 0.28 ± 0.03) was close to the diversity within the population (HS = 0.20 ± 0.01). A high mean coefficient of gene differentiation (GST = 0.29) reflected a high level of gene flow (Nm = 1.22), indicating high genetic differentiation among the populations. Analysis of Molecular Variance (AMOVA) showed 78% of intra-population differentiation, 21% among the population and 1% among the districts. The obtained results indicate the existence of a high level of genetic diversity in the cultivated Khasi mandarin populations, indicating the need for preservation of each existing population to revive the dying out orchards in northeast India.

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Genetic Investigation of Four Beluga Sturgeon (Huso huso, L.) Broodstocks for its Reintroduction in the Po River Basin

Environments ◽

10.3390/environments8040025 ◽

2021 ◽

Vol 8 (4) ◽

pp. 25

Author(s):

Caterina M. Antognazza ◽

Isabella Vanetti ◽

Vanessa De Santis ◽

Adriano Bellani ◽

Monica Di Francesco ◽

...

Keyword(s):

Genetic Diversity ◽

Mitochondrial Dna ◽

Genetic Variability ◽

River Basin ◽

Captive Breeding ◽

Conservation Strategies ◽

Huso Huso ◽

Po River ◽

Beluga Sturgeon ◽

Po River Basin

The reintroduction of the extinct beluga sturgeon (Huso huso L.), an anadromous species with economic and traditional relevance, is a priority in next conservation strategies in Northern Italy. The EU-LIFE NATURA project aims to reintroduce the beluga sturgeon in the Po River basin through a captive breeding program. Critical requirements for the success of the program are river connectivity and knowledge of genetic diversity of the selected broodstocks to ensure self-sustainability of reintroduced populations. Here, the four broodstocks used for the reintroduction of beluga sturgeon have been genetically screened, genotyping 13 loci and sequencing mitochondrial DNA cytochrome b (Cyt b) gene and the entire mitochondrial DNA control region (D-Loop). The four broodstocks showed a medium-high level of nuclear genetic variability and the presence of two sub-populations, evidencing a total level of inbreeding coefficients able to sustain the good potential as future breeders. Mitochondrial analyses showed a genetic variability comparable to wild populations, further strengthening the positive potential of the investigated broodstock. Therefore, this study, showed how the degree of genetic diversity found within the four broodstocks used for H. huso reintroduction in the Po River basin could be suitable to ensure the success of the program, avoiding the inbreeding depression associated with founder effect and captive breeding.

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The genetic legacy of fragmentation and overexploitation in the threatened medicinal African pepper-bark tree, Warburgia salutaris

Scientific Reports ◽

10.1038/s41598-020-76654-6 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Annae M. Senkoro ◽

Pedro Talhinhas ◽

Fernanda Simões ◽

Paula Batista-Santos ◽

Charlie M. Shackleton ◽

...

Keyword(s):

Genetic Diversity ◽

Habitat Degradation ◽

Random Mating ◽

Diversity Management ◽

Iucn Red List ◽

Ex Situ ◽

Management Plans ◽

Conservation Actions ◽

Genetic Diversity Management ◽

High Level

AbstractThe pepper-bark tree (Warburgia salutaris) is one of the most highly valued medicinal plant species worldwide. Native to southern Africa, this species has been extensively harvested for the bark, which is widely used in traditional health practices. Illegal harvesting coupled with habitat degradation has contributed to fragmentation of populations and a severe decline in its distribution. Even though the species is included in the IUCN Red List as Endangered, genetic data that would help conservation efforts and future re-introductions are absent. We therefore developed new molecular markers to understand patterns of genetic diversity, structure, and gene flow of W. salutaris in one of its most important areas of occurrence (Mozambique). In this study, we have shown that, despite fragmentation and overexploitation, this species maintains a relatively high level of genetic diversity supporting the existence of random mating. Two genetic groups were found corresponding to the northern and southern locations. Our study suggests that, if local extinctions occurred in Mozambique, the pepper-bark tree persisted in sufficient numbers to retain a large proportion of genetic diversity. Management plans should concentrate on maintaining this high level of genetic variability through both in and ex-situ conservation actions.

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Genetic variability and relationship among different accessions of Froriepia subpinata Bail (Gijavash) an endangered medicinal plant from Iran revealed by ISSR and IRAP markers

Advances in Horticultural Science ◽

10.36253/ahsc-8107 ◽

2021 ◽

Vol 35 (1) ◽

Author(s):

Abbas Jorkesh ◽

Yousef Hamidoghli ◽

Jamalali Olfati ◽

Habibollah Samizadeh ◽

Davood Bakhshi

Keyword(s):

Genetic Diversity ◽

Cluster Analysis ◽

Genetic Variability ◽

Medicinal Plant ◽

Genetic Information ◽

Conservation Strategies ◽

Polymorphic Band ◽

Mean Values ◽

Endangered Medicinal Plant ◽

Irap Markers

The genetic variability of Froriepia subpinata Ledeb. Bail., an endangered Iranian endemic species, has been estimated with a total of 52 accessions using 20 markers including ISSR and IRAP. The results showed the polymorphic band produced by primers was 82.3%. The best mean values of genetic diversity parameters observed in ISSRs markers, being UBC873, UBC811, and UBC873 the best primers tested. The similarity range among accessions was 34.45% to 93.3%. The cluster analysis classified the accessions into five main groups that in totally, accessions with similarity in region generally were clustered in the same group. Overall, present study could provide elementary information for formulation of conservation strategies and invaluable elementary genetic information for next breeding or designing conservation programs.

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Analysis of Genetic Diversity in three Kazakh Sheep using 12 Microsatellites

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i4.38.24336 ◽

2018 ◽

Vol 7 (4.38) ◽

pp. 122

Author(s):

Kairat Dossybayev ◽

Aizhan Mussayeva ◽

Bakytzhan Bekmanov ◽

Beibit Kulataev

Keyword(s):

Genetic Diversity ◽

Genetic Variability ◽

Mean Value ◽

Fixation Index ◽

Merino Sheep ◽

Str Markers ◽

Sheep Breeds ◽

Str Loci ◽

High Level ◽

Two Populations

The genetic structure of three Kazakh sheep breeds was examined by using 12 microsatellite loci. A total of 144 alleles were detected from the 12 STR loci, with a mean value of 12.0. The highest allele diversity was found at the locus CSRD247 (16 alleles). PIC value showed that all studied STR markers are more informative and appropriate for genetic analysis of three Kazakh sheep populations. Beside of INRA006, all markers had high level of genetic variability. As Fixation index shows, the excess of the heterozygosity was observed only in loci MAF065. Obtained number of private alleles in Edilbai, Kazakh Arkhar Merino and Kazakh Fine-wool sheep were 25, 17 and 15 respectively. Genetic diversity was higher in Edilbai population than in other two populations. The genetic variability was lower in Kazakh Arkhar Merino sheep than in the Edilbai and Kazakh Fine-wool sheep breeds. The genetic distance was the largest between Edilbai and Kazakh Arkhar Merinos. Also, the moderate differentiation was observed between Edilbai and Kazakh Arkhar Merinos.

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Population genetic variability and distribution of the endangered Greek endemic Cicer graecum under climate change scenarios

AoB Plants ◽

10.1093/aobpla/plaa007 ◽

2020 ◽

Vol 12 (2) ◽

Cited By ~ 2

Author(s):

Efthalia Stathi ◽

Konstantinos Kougioumoutzis ◽

Eleni M Abraham ◽

Panayiotis Trigas ◽

Ioannis Ganopoulos ◽

...

Keyword(s):

Climate Change ◽

Genetic Diversity ◽

Genetic Variability ◽

Hot Spot ◽

Extinction Risk ◽

Aflp Markers ◽

Ex Situ ◽

Dominant Factor ◽

Climate Change Scenarios ◽

Global Circulation Models

Abstract The Mediterranean hot spot includes numerous endemic and socio-economically important plant species seriously threatened by climate change and habitat loss. In this study, the genetic diversity of five populations of Cicer graecum, an endangered endemic species from northern Peloponnisos, Greece and a wild relative of the cultivated Cicer arietinum, was investigated using inter-simple sequence repeats (ISSRs) and amplified fragment length polymorphism (AFLP) markers in order to determine levels and structure of genetic variability. Nei’s gene diversity by ISSR and AFLP markers indicated medium to high genetic diversity at the population level. Moreover, AMOVA results suggest that most of the variation exists within (93 % for AFLPs and 65 % for ISSRs), rather than among populations. Furthermore, Principal Component Analysis based on ISSRs positively correlated the genetic differentiation among the populations to the geographic distances, suggesting that the gene flow among distant populations is limited. The ecological adaptation of C. graecum populations was also investigated by correlation of their genetic diversity with certain environmental variables. Aridity arose as the dominant factor positively affecting the genetic diversity of C. graecum populations. We modelled the realized climatic niche of C. graecum in an ensemble forecasting scheme under three different global circulation models and two climate change scenarios. In all cases, a severe range contraction for C. graecum is projected, highlighting the high extinction risk that is probably going to face during the coming decades. These results could be a valuable tool towards the implementation of an integrated in situ and ex situ conservation scheme approach for activating management programmes for this endemic and threatened species.

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Strategies for conservation of germplasm in endemic redwoods in the face of climate change: a review

Plant Genetic Resources ◽

10.1017/s1479262111000153 ◽

2011 ◽

Vol 9 (3) ◽

pp. 411-422 ◽

Cited By ~ 5

Author(s):

M. R. Ahuja

Keyword(s):

Climate Change ◽

Genetic Diversity ◽

Conservation Strategy ◽

Ex Situ ◽

Conservation Strategies ◽

Phenotypic Traits ◽

Coast Redwood ◽

Giant Sequoia ◽

The Face

This study reviews the various conservation strategies applied to the four redwood species, namely coast redwood (Sequoia sempervirens), Sierra redwood or giant sequoia (Sequoiadendron giganteum), dawn redwood (Metasequoia glyptostroboides) and South American redwood or alerce (Fitzroya cupressoides), which are endemic in the USA, China and South America, respectively. All four redwood genera belong to the family Cupressaceae; they are monospecific, share a number of common phenotypic traits, including red wood, and are threatened in their native ranges due to human activity and a changing climate. Therefore, the management objective should be to conserve representative populations of the native species with as much genetic diversity as possible for their future survival. Those representative populations exhibiting relatively high levels of genetic diversity should be selected for germplasm preservation and monitored during the conservation phase by using molecular markers. In situ and ex situ strategies for the preservation of germplasm of the redwoods are discussed in this study. A holistic in situ gene conservation strategy calls for the regeneration of a large number of diverse redwood genotypes that exhibit adequate levels of neutral and adaptive genetic variability, by generative and vegetative methods for their preservation and maintenance in their endemic locations. At the same time, it would be desirable to conserve the redwoods in new ex situ reserves, away from their endemic locations with similar as well as different environmental conditions for testing their growth and survival capacities. In addition, other ex situ strategies involving biotechnological approaches for preservation of seeds, tissues, pollen and DNA in genebanks should also be fully exploited in the face of global climate change.

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Genetic Diversity and Variability in Endangered Pantesco and Two Other Sicilian Donkey Breeds Assessed by Microsatellite Markers

The Scientific World JOURNAL ◽

10.1100/2012/648427 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 11

Author(s):

Salvatore Bordonaro ◽

Anna Maria Guastella ◽

Andrea Criscione ◽

Antonio Zuccaro ◽

Donata Marletta

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Genetic Variability ◽

Genetic Information ◽

Gene Diversity ◽

Genetic Distances ◽

Conservation Strategies ◽

Population Structure Analysis ◽

The Mean ◽

Differentiation Index

The genetic variability of Pantesco and other two Sicilian autochthonous donkey breeds (Ragusano and Grigio Siciliano) was assessed using a set of 14 microsatellites. The main goals were to describe the current differentiation among the breeds and to provide genetic information useful to safeguard the Pantesco breed as well as to manage Ragusano and Grigio Siciliano. In the whole sample, that included 108 donkeys representative of the three populations, a total of 85 alleles were detected. The mean number of alleles was lower in Pantesco (3.7), than in Grigio Siciliano and Ragusano (4.4 and 5.9, resp.). The three breeds showed a quite low level of gene diversity (He) ranging from 0.471 in Pantesco to 0.589 in Grigio. The overall genetic differentiation index (Fst) was quite high; more than 10% of the diversity was found among breeds. Reynolds’ () genetic distances, correspondence, and population structure analysis reproduced the same picture, revealing that, (a) Pantesco breed is the most differentiated in the context of the Sicilian indigenous breeds, (b) within Ragusano breed, two well-defined subgroups were observed. This information is worth of further investigation in order to provide suitable data for conservation strategies.

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Chloroplast microsatellites reveal genetic diversity and population structure in natural populations of Himalayan Cedar (Cedrus deodara (Roxb.) G. Don) in India

Silvae Genetica ◽

10.2478/sg-2020-0012 ◽

2020 ◽

Vol 69 (1) ◽

pp. 86-93

Author(s):

H. S. Ginwal ◽

Rajesh Sharma ◽

Priti Chauhan ◽

Kirti Chamling Rai ◽

Santan Barthwal

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Natural Populations ◽

Conservation Strategies ◽

Restricted Gene Flow ◽

Chloroplast Microsatellites ◽

Timber Species ◽

Western Himalayas ◽

Cedrus Deodara ◽

High Level

AbstractHimalayan cedar (Cedrus deodara) is one of the most important temperate timber species of Western Himalayas and is considered to be among the endangered conifer species in the region. Knowledge of genetic diversity and population structure will help guide gene conservation strategies for this species. Ten polymorphic chloroplast microsatellites (cpSSR) were used to study genetic diversity and population structure in twenty one natural populations of C. deodara throughout its entire distribution range in Western Himalayas. When alleles at each of the 10 loci were jointly analysed, 254 different haplotypes were identified among 1050 individuals. The cpSSRs indicate that C. deodara forests maintain a moderately high level of genetic diversity (mean h = 0.79 ). AMOVA analysis showed that most of the diversity in C. deodara occurs within populations. Bayesian analysis for population structure (BAPS) revealed spatial structuration of the variation (22 % of the total variation) and substructuring captured nineteen genetic clusters in the entire divisions of the populations. Most of the populations were clustered independently with minor admixtures. The distribution of genetic diversity and sub-structuring of C. deodara may be due to restricted gene flow due to geographic isolation, genetic drift, and natural selection. These findings indicated existence of genetically distinct and different high diversity and low diversity clusters, which are potential groups of populations that require attention for their conservation and management. The results are interpreted in context of future conservation plans for C. deodara.

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