High genetic diversity vs. low genetic differentiation in Nouelia insignis (Asteraceae), a narrowly distributed and endemic species in China, revealed by ISSR fingerprinting.
OBJECTIVE
Nouelia insignis Franch., a monotypic genus of the Asteraceae, is an endangered species endemic in Yunnan and Sichuan Provinces of China. Most of the populations are seriously threatened. Some of them are even at the brink of extinction. In this study, the genetic diversity and differentiation between populations of this species were examined in two drainage areas.


METHODS
DNA fingerprinting based on inter-simple sequence repeat polymorphisms was employed to detect the genetic variation and population structure in the species.


RESULTS
Genetic diversity at species level was high with P=65.05% (percentage of polymorphic loci) and Ht=0.2248 (total genetic diversity). The coefficient of genetic differentiation among populations, Gst, which was estimated by partitioning the total gene diversity, was 0.2529; whereas, the genetic differentiation between populations in the Jinsha and Nanpan drainage areas was unexpectedly low (Gst=0.0702).


CONCLUSIONS
Based on the genetic analyses of the DNA fingerprinting, recent habitat fragmentation may not have led to genetic differentiation or the loss of genetic diversity in the rare species. Spatial apportionment of fingerprinting polymorphisms provides a footprint of historical migration across geographical barriers. The high diversity detected in this study holds promise for conservation and restoration efforts to save the endangered species from extinction.
Luan
Shanshan
S
Laboratory of Biodiversity and Biogeography, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, PR China.
Chiang
Tzen-Yuh
TY
Gong
Xun
X
D019659:Asteraceae / Q000235:genetics*; D002681:China; D003247:Conservation of Natural Resources; D016172:DNA Fingerprinting; D018744:DNA, Plant; D017753:Ecosystem; D004777:Environment; D014644:Genetic Variation
D018744:DNA, Plant