scholarly journals High Genetic Diversity and Low Differentiation in Michelia shiluensis, an Endangered Magnolia Species in South China

Forests ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 469 ◽  
Author(s):  
Yanwen Deng ◽  
Tingting Liu ◽  
Yuqing Xie ◽  
Yaqing Wei ◽  
Zicai Xie ◽  
...  

Research Highlights: This study is the first to examine the genetic diversity of Michelia shiluensis (Magnoliaceae). High genetic diversity and low differentiation were detected in this species. Based on these results, we discuss feasible protection measures to provide a basis for the conservation and utilization of M. shiluensis. Background and Objectives: Michelia shiluensis is distributed in Hainan and Guangdong province, China. Due to human disturbance, the population has decreased sharply, and there is thus an urgent need to evaluate genetic variation within this species in order to identify an optimal conservation strategy. Materials and Methods: In this study, we used eight nuclear single sequence repeat (nSSR) markers and two chloroplast DNA (cpDNA) markers to assess the genetic diversity, population structure, and dynamics of 78 samples collected from six populations. Results: The results showed that the average observed heterozygosity (Ho), expected heterozygosity (He), and percentage of polymorphic loci (PPL) from nSSR markers in each population of M. shiluensis were 0.686, 0.718, and 97.92%, respectively. For cpDNA markers, the overall haplotype diversity (Hd) was 0.674, and the nucleotide diversity was 0.220. Analysis of markers showed that the genetic variation between populations was much lower based on nSSR than on cpDNA (10.18% and 77.56%, respectively, based on an analysis of molecular variance (AMOVA)). Analysis of the population structure based on the two markers shows that one of the populations (DL) is very different from the other five. Conclusions: High genetic diversity and low population differentiation of M. shiluensis might be the result of rich ancestral genetic variation. The current decline in population may therefore be due to human disturbance rather than to inbreeding or genetic drift. Management and conservation strategies should focus on maintaining the genetic diversity in situ, and on the cultivation of seedlings ex-situ for transplanting back to their original habitat.

2020 ◽  
Author(s):  
Rong Tang ◽  
Erxi Liu ◽  
Yazhou Zhang ◽  
Johann Schinnerl ◽  
Weibang Sun ◽  
...  

Abstract Background: Amorphophallus albus P. Y. Liu & J. F. Chen (Araceae) is a plant species with extremely small populations (PSESP) and an important economic crop endemic to dry-hot valleys along the Jinsha River. In order to gain information for sustaining the development and conservation of A. albus, we studied the genetic diversity and population structure of this species using microsatellite markers (SSR). In this study, we analysed 364 individuals belonging to 24 populations, including four wild populations and three ex-situ cultivated populations, collected in the provinces Yunnan, Sichuan and Hubei. Results: The population genetic analyses indicated that A. albus possesses moderate genetic diversity with the percentage of polymorphic loci (PPL) from 69.23% to 100%, an expected heterozygosity (He) of 0.504 and an average Shannon's Information Index (I) 0.912. Analysis of molecular variance (AMOVA) indicated that most of the variance (71%) resided within populations and the estimated gene flow (Nm) was 0.61. The results of UPGMA cluster tree, STRUCTURE analyses together with the Mantel test (R2 = 0.352, P < 0.01) indicated that geographically closely located populations are clustered together with some exceptions. Conclusions: Our results showed that A. albus still possesses moderate genetic variation in most of the studied populations, and for now, most cultivated populations were naturally distributed but still some reintroduction exists. For sustaining the present genetic variation, some protections measures are necessary for the wild populations and also for the cultivated ones with high genetic diversity.


2019 ◽  
Author(s):  
Rong Tang ◽  
Erxi Liu ◽  
Yazhou Zhang ◽  
Johann Schinnerl ◽  
Weibang Sun ◽  
...  

Abstract Background Amorphophallus albus P. Y. Liu & J. F. Chen (Araceae) is a plant species with extremely small populations (PSESP) and important economic crop endemic to dry-hot valleys along the Jinsha River. In order to gain information for sustaining the development and conservation of A. albus , we studied the genetic diversity and population structure of this species using microsatellite markers (SSR). In this study, we analyzed 364 individuals belonging to 24 populations, including four wild populations and three ex-situ cultivated populations, collected in the provinces Yunnan, Sichuan and Hubei.Results The population genetic analyses indicated that A. albus possesses moderate genetic diversity with the percentage of polymorphic loci ( PPL ) from 69.23% to 100%, an expected heterozygosity ( He ) of 0.504 and an average Shannon's Information Index ( I ) 0.912. Analysis of molecular variance (AMOVA) indicated that most of the variance (71%) resided within populations and the estimated gene flow ( Nm ) was 0.61. The results of UPGMA cluster tree, STRUCTURE analyses together with the Mantel test (R 2 = 0.352, P < 0.01) indicated that geographically closely located populations are cluster together with some exceptions.Conclusions Our results showed that A. albus still possesses moderate genetic variation in most of the studied populations, and for now, most cultivated populations were naturally distributed but still some reintroduction exists. For sustaining the present genetic variation, some protections measures are necessary for the wild populations and also for the cultivated ones with high genetic diversity.


BMC Genetics ◽  
2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Rong Tang ◽  
Erxi Liu ◽  
Yazhou Zhang ◽  
Johann Schinnerl ◽  
Weibang Sun ◽  
...  

Abstract Background Amorphophallus albus P. Y. Liu & J. F. Chen (Araceae) is a plant species with extremely small populations (PSESP) and an important economic crop endemic to dry-hot valleys along the Jinsha River. In order to gain information for sustaining the development and conservation of A. albus, we studied the genetic diversity and population structure of this species using microsatellite markers (SSR). In this study, we analysed 364 individuals belonging to 24 populations, including four wild populations and three ex-situ cultivated populations, collected in the provinces Yunnan, Sichuan and Hubei. Results The population genetic analyses indicated that A. albus possesses moderate genetic diversity with the percentage of polymorphic loci (PPL) from 69.23 to 100%, an expected heterozygosity (He) of 0.504 and an average Shannon’s Information Index (I) 0.912. Analysis of molecular variance (AMOVA) indicated that most of the variance (71%) resided within populations and the estimated gene flow (Nm) was 0.61. The results of UPGMA cluster tree, STRUCTURE analyses together with the Mantel test (R2 = 0.352, P < 0.01) indicated that geographically closely located populations are clustered together with some exceptions. Conclusions Our results showed that A. albus still possesses moderate genetic variation in most of the studied populations, and for now, most cultivated populations were naturally distributed but still some reintroduction exists. For sustaining the present genetic variation, some protections measures are necessary for the wild populations and also for the cultivated ones with high genetic diversity.


PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10274 ◽  
Author(s):  
Mirella Pupo Santos ◽  
João V.S. Rabelo Araujo ◽  
Arthur V. Sant’anna Lopes ◽  
Julio Cesar Fiorio Vettorazzi ◽  
Marcela Santana Bastos Boechat ◽  
...  

Background Two endemic lycophyte species Isoetes cangae and Isoetes serracarajensis have been recently described in the State of Pará in the Amazon forest located in northern Brazil. Isoetes L. has survived through three mass extinctions. Plants are considered small-sized, heterosporous, and can display a great diversity of physiological adaptations to different environments. Thus, the current study aimed to estimate the genetic variation of the populations of I. cangae and I. serracarajensis to generate information about their different mechanisms for survival at the same geographical location that could point to different reproductive, adaptative and dispersal strategies and should be considered for effective conservation strategies. Methods The genetic diversity and population structure of I. cangae and I. serracarajensis were investigated using Inter Simple Sequence Repeat (ISSR) molecular markers. Total genomic DNA was isolated, and the genetic diversity parameters were calculated. Results The sixteen primers produced 115 reproducible bands, 87% of which were polymorphic. A high level of polymorphic loci (81.74% and 68.48%) and a high Shannon index (Sh = 0.376 and 0.289) were observed for I. cangae and I. serracarajensis, respectively. The coefficient of genetic differentiation between population areas (GST) showed a higher value in I. serracarajensis (0.5440). Gene flow was higher in I. cangae (1.715) and lower in I. serracarajensis populations (0.419). Overall, the results further show that I. serracarajensis and I. cangae are two species with considerable genetic variation and that these differences may reflect their habitats and modes of reproduction. These results should be considered in the development of effective conservation strategies for both species.


2019 ◽  
Vol 11 (20) ◽  
pp. 5863 ◽  
Author(s):  
Qingqing Yu ◽  
Qian Liu ◽  
Yi Xiong ◽  
Yanli Xiong ◽  
Zhixiao Dong ◽  
...  

Elymus breviaristatus is a grass species only distributed in the southeast of Qinghai-Tibetan Plateau (QTP), which has suffered from serious habitat fragmentation. Therefore, understanding patterns of genetic diversity within and among natural E. breviaristatus populations could provide insight for future conservation strategies. In this study, sequence-related amplified polymorphism markers were employed to investigate the genetic diversity and hierarchical structure of seven E. breviaristatus populations from QTP, China. Multiple measures of genetic diversity indicated that there is low to moderate genetic variation within E. breviaristatus populations, consistent with its presumed mating system. In spite of its rarity, E. breviaristatus presented high genetic diversity that was equivalent to or even higher than that of widespread species. Bayesian clustering approaches, along with clustering analysis and principal coordinate analysis partitioned the studied populations of E. breviaristatus into five genetic clusters. Differentiation coefficients (Fst, GST, etc.) and AMOVA analysis revealed considerable genetic divergence among different populations. BARRIER analyses indicated that there were two potential barriers to gene flow among the E. breviaristatus populations. Despite these patterns of differentiation, genetic distances between populations were independent of geographic distances (r = 0.2197, p = 0.2534), indicating little isolation by distance. Moreover, despite detecting a common outlier by two methods, bioclimatic factors (altitude, annual mean temperature, and annual mean precipitation) were not related to diversity parameters, indicating little evidence for isolation caused by the environment. These patterns of diversity within and between populations are used to propose a conservation strategy for E. breviaristatus.


2011 ◽  
Vol 9 (3) ◽  
pp. 411-422 ◽  
Author(s):  
M. R. Ahuja

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.


2021 ◽  
Vol 22 (10) ◽  
Author(s):  
Zulfahmi Zulfahmi ◽  
Parjanto Parjanto ◽  
Edi Purwanto ◽  
Ahmad Yunus

Abstract. Zulfahmi, Parjanto, Purwanto E, Yunus A. 2021. Genetic diversity and population structure of Eurycoma apiculata in Eastern Sumatra, Indonesia. Biodiversitas 22: 4431-4439. Information on genetic variation within and among populations of Eurycoma apiculata plants is important to develop strategies for their conservation, sustainable use, and genetic improvement. To date, no information on genetic variation within and among populations of the E. apiculata has been reported. This study aims to assess genetic diversity within and among populations of E. apiculata based on RAPD markers, and to determine populations to collect E. apiculata genetic material for conservation and breeding programs. Young leaves of E. apiculata were collected from six natural populations. Fifteen RAPD primers were used to assess the genetic diversity of each population. The data obtained were analyzed with POPGEN and Arlequin software. The amplification results of 15 selected primers produced 3-16 loci with all primers 100% polymorphic. At the species level, the mean allele per locus (Na), number of effective alleles (Ne), percentage of polymorphic loci (PPL), Nei’s gene diversity index (He) and Shannon information index (I) were 2.000, 1.244, 100%, 0.167, and 0.286, respectively. At the population level, the mean values for Na, Ne, PPL, He and I were 1.393, 1.312, 39.27%, 0.119, and 0.186, respectively. The highest value of gene diversity within population (He) was found in the Lingga-1 population and the lowest value was found in the Rumbio population. The value of genetic differentiation among populations (GST) of E. apiculata is 0.284, consistent with the results of the AMOVA analysis which found that genetic variation among populations was 23.14%, indicates that the genetic variation of E. apiculata was more stored within populations than among populations. The gene flow (Nm) value of E. apiculata was 1.259 migrants per generation among populations. The Nm value of this species was high category, and could inhibit genetic differentiation among populations. The clustering of E. apiculata population based on the UPGMA dendrogram and PCA was inconsistent with its geographic distribution, reflecting the possibility that genes migration occurred between islands in the past. The main finding of this study was the genetic variation of the E. apiculata mostly stored within the population. Therefore, the population with the highest genetic diversity is a priority for in-situ conservation, and collection of E. apiculata genetic material for ex-situ conservation and breeding programs should be carried out minimum from Lingga-1 and Pokomo populations.


Biologia ◽  
2014 ◽  
Vol 69 (3) ◽  
Author(s):  
Manikantan Kuttapetty ◽  
Padmesh Pillai ◽  
Reji Varghese ◽  
Soorimuthu Seeni

AbstractRhododendron arboreum of the family Ericaceae represents one of the ancient relict tree species of the genus showing extreme disjunction in the Indian subcontinent. It is represented by two sub-species viz., ssp. arboreum Smith in the forests of north-eastern India (temperate) and spp. nilagiricum (Zenker) Tagg distributed in the southern Western Ghats (tropical) of India with apparently no distribution in the intervening plains. 35 Samples corresponding to different locations in the tropical montane forests of Nilgiris and temperate forests of northeast India were analyzed for distribution of genetic variation using 25 random primers. Relatively high genetic diversity was measured in the temperate populations (Ht = 0.21; Nm = 1.13) than tropical Rhododendrons. The hierarchical analysis of molecular variance showed that among the total variance, 25% is residing within populations while 63% of variance is among regions apparently revealing that disjunct distribution has structured genetic differentiation pattern in this species. Grouping of samples was in conformity with their spatial distribution, which was confirmed by UPGMA cluster analysis and PCA scatter plot. The taxon with its unique distribution pattern and wide cross compatibility between sub-species is however threatened by low genetic variation and gene flow that catalyses it’s shifting towards genetic drift and hence long-term conservation strategies need to be formulated particularly for the tropical Rhododendron sub-species. Among the various hypotheses and theory proposed to explain the Malayan affinity in the flora and fauna of Western Ghats, Satpura hypothesis based on dispersal model of distribution largely explains the discontinues distribution of R. arboreum.


PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0260651
Author(s):  
Sintayehu Admas ◽  
Kassahun Tesfaye ◽  
Teklehaimanot Haileselassie ◽  
Eleni Shiferaw ◽  
K. Colton Flynn

Evaluation of the genetic diversity and an understanding of the genetic structure and relationships of chickpea genotypes are valuable to design efficient germplasm conservation strategies and crop breeding programs. Information is limited, in these regards, for Ethiopian chickpea germplasms. Therefore, the present study was carried out to estimate the genetic diversity, population structure, and relationships of 152 chickpea genotypes using simple sequence repeats (SSR) markers. Twenty three SSR markers exhibited polymorphism producing a total of 133 alleles, with a mean of 5.8 alleles per locus. Analyses utilizing various genetic-based statistics included pairwise population Nei’s genetic distance, heterozygosity, Shannon’s information index, polymorphic information content, and percent polymorphism. These analyses exemplified the existence of high genetic variation within and among chickpea genotypes. The 152 genotypes were divided into two major clusters based on Nei’s genetic distances. The exotic genotypes were grouped in one cluster exclusively showing that these genotypes are distinct to Ethiopian genotypes, while the patterns of clustering of Ethiopian chickpea genotypes based on their geographic region were not consistent because of the seed exchange across regions. Model-based population structure clustering identified two discrete populations. These finding provides useful insight for chickpea collections and ex-situ conservation and national breeding programs for widening the genetic base of chickpea.


2019 ◽  
Vol 110 (7) ◽  
pp. 844-856 ◽  
Author(s):  
Chin-Hong Ng ◽  
Soon-Leong Lee ◽  
Lee-Hong Tnah ◽  
Kevin K S Ng ◽  
Chai-Ting Lee ◽  
...  

Abstract Southeast Asian rainforests at upper hill elevations are increasingly vulnerable to degradation because most lowland forest areas have been converted to different land uses. As such, understanding the genetics of upper hill species is becoming more crucial for their future management and conservation. Shorea platyclados is an important, widespread upper hill dipterocarp in Malaysia. To elucidate the genetic structure of S. platyclados and ultimately provide guidelines for a conservation strategy for this species, we carried out a comprehensive study of the genetic diversity and demographic history of S. platyclados. Twenty-seven populations of S. platyclados across its range in Malaysia were genotyped at 15 polymorphic microsatellite loci and sequenced at seven noncoding chloroplast DNA (cpDNA) regions. A total of 303 alleles were derived from the microsatellite loci, and 29 haplotypes were identified based on 2892 bp of concatenated cpDNA sequences. The populations showed moderately high genetic diversity (mean HE = 0.680 for microsatellite gene diversity and HT = 0.650 for total haplotype diversity) and low genetic differentiation (FST = 0.060). Bayesian clustering divided the studied populations into two groups corresponding to western and eastern Malaysia. Bottleneck analysis did not detect any recent bottleneck events. Extended Bayesian skyline analyses showed a model of constant size for the past population history of this species. Based on our findings, priority areas for in situ and ex situ conservation and a minimum population size are recommended for the sustainable utilization of S. platyclados.


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