Limits...
Genetic diversity and population differentiation of Calanthe tsoongiana, a rare and endemic orchid in China.

Qian X, Wang CX, Tian M - Int J Mol Sci (2013)

Bottom Line: High-level genetic differentiation among populations was detected based on analysis of molecular variance (AMOVA), indicating potential limited gene flow.No significant relationship was observed between genetic and geographic distances among the sampled populations.Based on the findings, several conservation strategies were proposed for the preservation of this threatened species.

View Article: PubMed Central - PubMed

Affiliation: Research Institution of Subtropical Forestry, Chinese Academy of Forestry, 73, Daqiao Road, Fuyang 311400, Zhejiang, China. tmin115@126.com.

ABSTRACT
Calanthe tsoongiana is a rare terrestrial orchid endemic to China, and this species has experienced severe habitat loss and fragmentation. Inter-simple sequence repeat (ISSR) markers were employed to assess the genetic diversity and differentiation of six populations of C. tsoongiana. Based on 124 discernible fragments yielded by eleven selected primers, high genetic diversity was revealed at the species level; however, genetic diversity at the population level was relatively low. High-level genetic differentiation among populations was detected based on analysis of molecular variance (AMOVA), indicating potential limited gene flow. No significant relationship was observed between genetic and geographic distances among the sampled populations. These results suggested that restricted gene flow might be due to habitat fragmentation and reduced population size as a result of human activities. Based on the findings, several conservation strategies were proposed for the preservation of this threatened species.

Show MeSH

Related in: MedlinePlus

Population structure of six populations of C. tsoongiana prepared using the STRUCTURE program (Pritchard Lab, Stanford University, CA, USA).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3821621&req=5

f4-ijms-14-20399: Population structure of six populations of C. tsoongiana prepared using the STRUCTURE program (Pritchard Lab, Stanford University, CA, USA).

Mentions: The Nei’s genetic distance among the C. tsoongiana populations ranged from 0.229 (between LA and WYS) to 0.638 (between WN and WYS) (Table 3). The Mantel test indicated that there was no significant correlation between genetic distance and geographic distance (r = 0.088, p = 0.306) (Figure 1). The UPGMA dendrogram showed general separation of the six populations, but a few individuals from four populations (RJ, JR, SZ and TR) were cluster mixed (not shown). All 104 plants were clustered into two major groups, three populations (LA, WYS and RJ) and two individuals from SZ and two from TR formed the first group, while the second group included the remaining three populations (SZ, TR and WN). Two-dimensional principal coordinate analysis (PCoA) of the six populations accounted for 43.94% (first axis) and 21.14% (second axis) of total variance, respectively (Figure 2). The first axis separated the six populations into two major groups, which accorded with cluster analysis, and the LA and WYS populations occupied a similar position along the second axis. There was a clear peak in the value of ΔK (127.2) at K = 2 (Figure 3). Therefore K = 2 best fit the data. The proportions of all individuals were assigned into two clusters (Figure 4), but the RJ and SZ populations displayed some degree of mixed ancestry, which was analogous to the result of UPGMA dendrogram.


Genetic diversity and population differentiation of Calanthe tsoongiana, a rare and endemic orchid in China.

Qian X, Wang CX, Tian M - Int J Mol Sci (2013)

Population structure of six populations of C. tsoongiana prepared using the STRUCTURE program (Pritchard Lab, Stanford University, CA, USA).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3821621&req=5

f4-ijms-14-20399: Population structure of six populations of C. tsoongiana prepared using the STRUCTURE program (Pritchard Lab, Stanford University, CA, USA).
Mentions: The Nei’s genetic distance among the C. tsoongiana populations ranged from 0.229 (between LA and WYS) to 0.638 (between WN and WYS) (Table 3). The Mantel test indicated that there was no significant correlation between genetic distance and geographic distance (r = 0.088, p = 0.306) (Figure 1). The UPGMA dendrogram showed general separation of the six populations, but a few individuals from four populations (RJ, JR, SZ and TR) were cluster mixed (not shown). All 104 plants were clustered into two major groups, three populations (LA, WYS and RJ) and two individuals from SZ and two from TR formed the first group, while the second group included the remaining three populations (SZ, TR and WN). Two-dimensional principal coordinate analysis (PCoA) of the six populations accounted for 43.94% (first axis) and 21.14% (second axis) of total variance, respectively (Figure 2). The first axis separated the six populations into two major groups, which accorded with cluster analysis, and the LA and WYS populations occupied a similar position along the second axis. There was a clear peak in the value of ΔK (127.2) at K = 2 (Figure 3). Therefore K = 2 best fit the data. The proportions of all individuals were assigned into two clusters (Figure 4), but the RJ and SZ populations displayed some degree of mixed ancestry, which was analogous to the result of UPGMA dendrogram.

Bottom Line: High-level genetic differentiation among populations was detected based on analysis of molecular variance (AMOVA), indicating potential limited gene flow.No significant relationship was observed between genetic and geographic distances among the sampled populations.Based on the findings, several conservation strategies were proposed for the preservation of this threatened species.

View Article: PubMed Central - PubMed

Affiliation: Research Institution of Subtropical Forestry, Chinese Academy of Forestry, 73, Daqiao Road, Fuyang 311400, Zhejiang, China. tmin115@126.com.

ABSTRACT
Calanthe tsoongiana is a rare terrestrial orchid endemic to China, and this species has experienced severe habitat loss and fragmentation. Inter-simple sequence repeat (ISSR) markers were employed to assess the genetic diversity and differentiation of six populations of C. tsoongiana. Based on 124 discernible fragments yielded by eleven selected primers, high genetic diversity was revealed at the species level; however, genetic diversity at the population level was relatively low. High-level genetic differentiation among populations was detected based on analysis of molecular variance (AMOVA), indicating potential limited gene flow. No significant relationship was observed between genetic and geographic distances among the sampled populations. These results suggested that restricted gene flow might be due to habitat fragmentation and reduced population size as a result of human activities. Based on the findings, several conservation strategies were proposed for the preservation of this threatened species.

Show MeSH
Related in: MedlinePlus