scholarly journals How much genetic variation is stored in the endangered and fragmented shrub Tetraena mongolica Maxim?

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5645 ◽  
Author(s):  
Yingbiao Zhi ◽  
Zhonglou Sun ◽  
Ping Sun ◽  
Kai Zhao ◽  
Yangnan Guo ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Background ◽  
Yellow River ◽  
Demographic History ◽  
Population Decline ◽  
Mountain Range ◽  
Population Demography ◽  
High Genetic Diversity ◽  
Nuclear Microsatellite ◽  
Over Exploitation

Tetraena mongolica Maxim (Zygophyllaceae) is an endangered species endemic to western Inner Mongolia and China, and is currently threatened by habitat loss and human over-exploitation. We explored the genetic background, its genetic diversity, population structure, and demographic history, based on 12 polymorphic nuclear microsatellite loci. Our results indicated high genetic diversity in extant populations, but no distinguishable gene cluster corresponding with a specific biogeography. Population demography analysis using a MSVAR indicated a strong, recent population decline approximately 5,455 years ago. These results suggest that the Yellow River and Zhuozi Mountain range may not prevent pollination between populations. Finally, we surmised that the population demography of T. mongolica was likely to have been affected by early mankind activities.

scholarly journals Genetic assessment reveals no population substructure and divergent regional and sex-specific histories in the Chachapoyas from northeast Peru

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0244497
Author(s):  
Evelyn K. Guevara ◽  
Jukka U. Palo ◽  
Sanni Översti ◽  
Jonathan L. King ◽  
Maria Seidel ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Demographic History ◽  
Population Decline ◽  
Population Substructure ◽  
Gene Pools ◽  
Population Declines ◽  
Montane Forests ◽  
High Genetic Diversity ◽  
Spanish Conquest

Many native populations in South America have been severely impacted by two relatively recent historical events, the Inca and the Spanish conquest. However decisive these disruptive events may have been, the populations and their gene pools have been shaped markedly also by the history prior to the conquests. This study focuses mainly on the Chachapoya peoples that inhabit the montane forests on the eastern slopes of the northern Peruvian Andes, but also includes three distinct neighboring populations (the Jívaro, the Huancas and the Cajamarca). By assessing mitochondrial, Y-chromosomal and autosomal diversity in the region, we explore questions that have emerged from archaeological and historical studies of the regional culture (s). These studies have shown, among others, that Chachapoyas was a crossroads for Coast-Andes-Amazon interactions since very early times. In this study, we examine the following questions: 1) was there pre-Hispanic genetic population substructure in the Chachapoyas sample? 2) did the Spanish conquest cause a more severe population decline on Chachapoyan males than on females? 3) can we detect different patterns of European gene flow in the Chachapoyas region? and, 4) did the demographic history in the Chachapoyas resemble the one from the Andean area? Despite cultural differences within the Chachapoyas region as shown by archaeological and ethnohistorical research, genetic markers show no significant evidence for past or current population substructure, although an Amazonian gene flow dynamic in the northern part of this territory is suggested. The data also indicates a bottleneck c. 25 generations ago that was more severe among males than females, as well as divergent population histories for populations in the Andean and Amazonian regions. In line with previous studies, we observe high genetic diversity in the Chachapoyas, despite the documented dramatic population declines. The diverse topography and great biodiversity of the northeastern Peruvian montane forests are potential contributing agents in shaping and maintaining the high genetic diversity in the Chachapoyas region.

scholarly journals High genetic diversity and demographic history of captive Siamese and Saltwater crocodiles suggest the first step toward the establishment of a breeding and reintroduction program in Thailand

PLoS ONE ◽  
2017 ◽  
Vol 12 (9) ◽  
pp. e0184526 ◽  
Author(s):  
Sorravis Lapbenjakul ◽  
Watcharaporn Thapana ◽  
Panupon Twilprawat ◽  
Narongrit Muangmai ◽  
Thiti Kanchanaketu ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Demographic History ◽  
High Genetic Diversity ◽  
History Of

scholarly journals Population Genetic Structure and Genetic Diversity in Twisted-Jaw Fish, Belodontichthys truncatus Kottelat & Ng, 1999 (Siluriformes: Siluridae), from Mekong Basin

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Surapon Yodsiri ◽  
Komgrit Wongpakam ◽  
Adisak Ardharn ◽  
Chadaporn Senakun ◽  
Sutthira Khumkratok
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Demographic History ◽  
Hydropower Plant ◽  
Mekong River ◽  
Demographic Expansion ◽  
High Genetic Diversity ◽  
History Analysis ◽  
History Of ◽  
Important Food Source

The Mekong River and its tributaries possess the second highest diversity in fish species in the world. However, the fish biodiversity in this river is threatened by several human activities, such as hydropower plant construction. Understanding the genetic diversity and genetic structure of the species is important for natural resource management. Belodontichthys truncatus Kottelat & Ng is endemic to the Mekong River basin and is an important food source for people in this area. In this study, the genetic diversity, genetic structure, and demographic history of the twisted-jaw fish, B. truncatus, were investigated using mitochondrial cytochrome b gene sequences. A total of 124 fish specimens were collected from 10 locations in the Mekong and its tributaries. Relatively high genetic diversity was found in populations of B. truncatus compared to other catfish species in the Mekong River. The genetic structure analysis revealed that a population from the Chi River in Thailand was genetically significantly different from other populations, which is possibly due to the effect of genetic drift. Demographic history analysis indicated that B. truncatus has undergone recent demographic expansion dating back to the end of the Pleistocene glaciation.

scholarly journals Genetic characterization of Cycas panzhihuaensis (Cycadaceae): crisis lurks behind a seemingly bright prospect

2018 ◽  
Author(s):  
Siyue Xiao ◽  
Yunheng Ji ◽  
Jian Liu ◽  
Xun Gong
Keyword(s):  
Genetic Diversity ◽  
Genetic Characterization ◽  
Extinction Risk ◽  
Demographic History ◽  
Single Copy ◽  
Jinsha River ◽  
High Genetic Diversity ◽  
Natural Reserve ◽  
Endangered Status

Background Cycas panzhihuaensis L. Zhou & S. Y. Yang (Cycadaceae) is an endangered gymnosperm species endemic in the dry-hot valley of Jinsha River basin from southwest China. Although the wild C. panzhihuaensis population from Panzhihua Cycad Natural Reserve is well protected, other known populations that fall outside the natural reserve may preserve specific genetic resources while face with larger extinction risk because of lacking essential monitoring. Methods In this study, we analyzed the genetic diversity, phylogeographical structure and demographic history of C. panzhihuaensis from seven known locations so far by sequencing three chloroplastic DNA regions (psbA-trnH, psbM-trnD, and trnS-trnG), four single-copy nuclear genes (PHYP, AC5, HSP70, and AAT) from 61 individuals, and eleven microsatellite loci (SSR) from 102 individuals. Results and Discussion We found relative high genetic diversity within populations and high genetic differentiation among the populations of C. panzhihuaensis, which is similar with the other Asian inland cycads. Despite no significant phylogeographical structure was detected, small and unprotected populations possess higher genetic diversity and more unique haplotypes, which deserve due attention. Results of demographic dynamics suggest that human activity is the key factor that leads C. panzhihuaensis to endangered status. Basing on the genetic characterization of C. panzhihuaensis, we proposed several practical guidelines for the conservation of this species, especially for its small populations.

scholarly journals Yangtze River, an insignificant genetic boundary in tufted deer (Elaphodus cephalophus): the evidence from a first population genetics study

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2654 ◽  
Author(s):  
Zhonglou Sun ◽  
Tao Pan ◽  
Hui Wang ◽  
Mujia Pang ◽  
Baowei Zhang
Keyword(s):  
Gene Flow ◽  
Yangtze River ◽  
Population Decline ◽  
Molecular Ecology ◽  
Population Increase ◽  
The Yangtze River ◽  
Population Demography ◽  
Vector Autoregressions ◽  
High Genetic Diversity ◽  
Geographical Barrier

Great rivers were generally looked at as the geographical barrier to gene flow for many taxonomic groups. The Yangtze River is the third largest river in the world, and flows across South China and into the East China Sea. Up until now, few studies have been carried out to evaluate its effect as a geographical barrier. In this study, we attempted to determine the barrier effect of the Yangtze River on the tufted deer (Elaphodus cephalophus) using the molecular ecology approach. Using mitochondrial DNA control region (CR) sequences and 13 nuclear microsatellite loci, we explored the genetic structure and gene flow in two adjacent tufted deer populations (Dabashan and Wulingshan populations), which are separated by the Yangtze River. Results indicated that there are high genetic diversity levels in the two populations, but no distinguishable haplotype group or potential genetic cluster was detected which corresponded to specific geographical population. At the same time, high gene flow was observed between Wulingshan and Dabashan populations. The tufted deer populations experienced population decrease from 0.3 to 0.09 Ma BP, then followed by a distinct population increase. A strong signal of recent population decline (T= 4,396 years) was detected in the Wulingshan population by a Markov-Switching Vector Autoregressions(MSVAR) process population demography analysis. The results indicated that the Yangtze River may not act as an effective barrier to gene flow in the tufted deer. Finally, we surmised that the population demography of the tufted deer was likely affected by Pleistocene climate fluctuations and ancient human activities.

Genetic Diversity and Genetic Differentiation of Rheum palmatum by Chloroplast matK Sequences

2020 ◽  
Vol 10 (2) ◽  
pp. 96-103
Author(s):  
Xiaoqin Zhang ◽  
Na Lin ◽  
Liping Chen ◽  
Zunjing Zhang ◽  
Houxing Lei ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Distance ◽  
Diversity Index ◽  
Geographic Distance ◽  
High Genetic Diversity ◽  
Rheum Palmatum ◽  
Wild Resources ◽  
Nj Tree ◽  
Matk Sequence ◽  
Over Exploitation

Background: Rheum palmatum is a medically important plant in the Polygonaceae family. Its wild resources have been declining due to over-exploitation. It is important and urgent to investigate the genetic diversity for the conservation of R. palmatum. Methods: The Chloroplast DNA matK sequences were used to assess genetic diversity among and within populations in this species. The genetic diversity index was calculated by Dnasp, PERMUT and Arlequin 3.0 software, and a Neighbor-Joining (NJ)-tree was constructed by MEGA 5.0 software. Results: Nine haplotypes were obtained based on the matK sequence analysis in fifteen populations. We found a relatively high genetic diversity in species level (Hd = 0.7414), and the genetic diversity among populations (FST = 0.81582) was higher than that within populations (FSC = 0.69526) according to the AMOVA analysis. The genetic distance between populations ranged from 0 to 0.0044, which within populations ranged from 0 to 0.001761. There was a significant correlation between genetic distance and geographic distance (r = 0.601, P < 0.001) according to the SPSS analysis. Conclusion: The genetic diversity among populations was higher than that within populations due to geographic isolation and decline in gene flow among populations. This study is significant for further studies concerned with efficient collection and preservation of wild resource of R. palmatum.

scholarly journals Estimating the genetic diversity and structure of Quercus trojana Webb populations in Italy by SSRs: implications for management and conservation

2017 ◽  
Vol 47 (3) ◽  
pp. 331-339 ◽  
Author(s):  
Maddalena Carabeo ◽  
Marco Cosimo Simeone ◽  
Marcello Cherubini ◽  
Chiara Mattia ◽  
Francesca Chiocchini ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Eastern Mediterranean ◽  
Conservation Strategies ◽  
Gene Pools ◽  
High Genetic Diversity ◽  
Genetic Diversity And Structure ◽  
Main Gene ◽  
Nuclear Microsatellite ◽  
Fragmented Distribution ◽  
Management And Conservation

Studying the genetic diversity and structure of the current forest populations is essential for evaluating the ability to survive future biotic and abiotic changes and planning conservation strategies. Quercus trojana Webb is an eastern Mediterranean tree species with a fragmented distribution range, and its westernmost outposts are located in southern Italy. The demand for timber and cropland over the centuries has severely reduced its occurrence in this part of the range. We assessed the genetic diversity and structure of the extant Italian populations of Q. trojana and derived conservation guidelines. A total of 322 samples were genotyped with six polymorphic nuclear microsatellite markers. A high genetic diversity in all populations, two main gene pools, and a highly divergent single population were observed. Based on the allelic richness and heterozygosity estimation, we identified populations that can be considered as valuable source material for conservation programs and those requiring adequate measures to reestablish gene flow and reduce fragmentation. Finally, a comparison with a set of eastern Mediterranean samples indicated a relationship between the Italian and the Greek gene pools. The need to protect these marginal, disjunct populations was further reinforced.

scholarly journals Microsatellite variability reveals high genetic diversity and low genetic differentiation in a critical giant panda population

2011 ◽  
Vol 57 (6) ◽  
pp. 717-724 ◽  
Author(s):  
Jiandong Yang ◽  
Zhihe Zhang ◽  
Fujun Shen ◽  
Xuyu Yang ◽  
Liang Zhang ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Differentiation ◽  
Giant Panda ◽  
Population Decline ◽  
Management Strategies ◽  
Ailuropoda Melanoleuca ◽  
High Genetic Diversity ◽  
Giant Pandas ◽  
Allele Number ◽  
High Level

Abstract Understanding present patterns of genetic diversity is critical in order to design effective conservation and management strategies for endangered species. Tangjiahe Nature Reserve (NR) is one of the most important national reserves for giant pandas Ailuropoda melanoleuca in China. Previous studies have shown that giant pandas in Tangjiahe NR may be threatened by population decline and fragmentation. Here we used 10 microsatellite DNA markers to assess the genetic variability in the Tangjiahe population. The results indicate a low level of genetic differentiation between the Hongshihe and Motianling subpopulations in the reserve. Assignment tests using the Bayesian clustering method in STRUCTURE identified one genetic cluster from 42 individuals of the two subpopulations. All individuals from the same subpopulation were assigned to one cluster. This indicates high gene flow between subpopulations. F statistic analyses revealed a low FIS-value of 0.024 in the total population and implies a randomly mating population in Tangjiahe NR. Additionally, our data show a high level of genetic diversity for the Tangjiahe population. Mean allele number (A), Allelic richness (AR) and mean expected heterozygosity (HE) for the Tangjiahe population was 5.9, 5.173 and 0.703, respectively. This wild giant panda population can be restored through concerted effort.

scholarly journals Genetic Diversity among Cowpea (Vigna unguiculata (L.) Walp.) Landraces Suggests Central Mozambique as an Important Hotspot of Variation

Agronomy ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1893
Author(s):  
Ana Maria Figueira Gomes ◽  
David Draper ◽  
Pedro Talhinhas ◽  
Paula Batista Santos ◽  
Fernanda Simões ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Vigna Unguiculata ◽  
African Countries ◽  
High Genetic Diversity ◽  
Ecological Zones ◽  
Nuclear Microsatellite ◽  
Tropical Areas ◽  
Other World ◽  
High Level

Cowpea is a multiple-purpose drought-tolerant leguminous pulse crop grown in several dry tropical areas. Its domestication center is thought to be East or West Africa, where a high level of genetic diversity is apparently still found. However, detailed genetic information is lacking in many African countries, limiting the success of breeding programs. In this work, we assessed the genetic variation and gene flow in 59 Vigna unguiculata (cowpea) accessions from 10 landraces spanning across six agro-ecological zones of Mozambique, based on nuclear microsatellite markers. The results revealed the existence of high genetic diversity between the landraces, even in comparison to other world regions. Four genetic groups were found, with no specific geographic pattern, suggesting the presence of gene flow between landraces. In comparison, the two commercial varieties had lower values of genetic diversity, although still close to the ones found in local landraces. The high genetic diversity found in Mozambique sustains the importance of local genetic resources and farm protection to enhance genetic diversity in modern varieties of cowpea worldwide.

scholarly journals Bottlenecked but long-lived: high genetic diversity retained in white-tailed eagles upon recovery from population decline

2006 ◽  
Vol 2 (2) ◽  
pp. 316-319 ◽  
Author(s):  
Frank Hailer ◽  
Björn Helander ◽  
Alv O Folkestad ◽  
Sergei A Ganusevich ◽  
Steinar Garstad ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Generation Time ◽  
Population Decline ◽  
High Genetic Diversity ◽  
Effective Time ◽  
Total Genetic Diversity ◽  
Persistent Pollutants ◽  
Conservation Actions ◽  
Ringing Data ◽  
Loss Of Genetic Diversity

Most of the white-tailed eagle ( Haliaeetus albicilla ) populations in Europe experienced dramatic declines during the twentieth century. However, owing to intense conservation actions and the ban of DDT and other persistent pollutants, populations are currently recovering. We show that despite passing through demographic bottlenecks, white-tailed eagle populations have retained significant levels of genetic diversity. Both genetic and ringing data indicate that migration between populations has not been a major factor for the maintenance of genetic variability. We argue that the long generation time of eagles has acted as an intrinsic buffer against loss of genetic diversity, leading to a shorter effective time of the experienced bottleneck. Notably, conservation actions taken in several small sub-populations have ensured the preservation of a larger proportion of the total genetic diversity than if conservation had focused on the population stronghold in Norway. For conservation programmes targeting other endangered, long-lived species, our results highlight the possibility for local retention of high genetic diversity in isolated remnant populations.

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