Abstract

Background

Nelumbo nucifera Gaertn., a perennial aquatic macrophyte species, has been cultivated in several Asian countries for its economic importance, and medicinal uses. Two distinct ecotypes of the species are recognized based on the geographical location where the genotypes are adapted, i.e., tropical lotus and temperate lotus. The genetic diversity levels and differentiation of the tropical lotus from poorly studied geographic regions still remain unclear. Here, the population genetic diversity and structure of 15 tropical lotus populations sampled from the previous understudied natural distribution ranges, including India, Thailand, and Australia, were assessed using nine polymorphic SSR markers.

Results

The SSR markers used to genotype the 216 individuals yielded 65 alleles. The highest and lowest genetic diversity estimates were found in Thailand and Indian populations, respectively. STRUCTURE analysis revealed three distinct genetic clusters, with relatively low admixtures, supported by PCoA cluster analysis. Low levels of gene flow (mean N⁠m = 0.346) among the three genetic clusters signified the Mantel test for isolation by distance, revealing the existence of a positive correlation between the genetic and geographic distances (r = 0.448, P = 0.004). Besides, AMOVA analysis revealed a higher variation among populations (59.98%) of the three groups. Overall, the populations used in this study exposed a high level of genetic differentiation (FST = 0.596).

Conclusions

The nine polymorphic microsatellite markers used in our study sufficiently differentiated the fifteen tropical N. nucifera populations based on geography. These populations presented different genetic variability, thereby confirming that populations found in each country are unique. The low genetic diversity (HE = 0.245) could be explained by limited gene flow and clonal propagation. Conserving the available diversity using various conservation approaches is essential to enable the continued utilization of this economically important crop species. We, therefore, propose that complementary conservation approaches ought to be introduced to conserve tropical lotus, depending on the genetic variations and threat levels in populations.

Details

Title
The level of genetic diversity and differentiation of tropical lotus, Nelumbo nucifera Gaertn. (Nelumbonaceae) from Australia, India, and Thailand
Author
Mekbib Yeshitila 1 ; Shi-Xu, Huang 2 ; Ngarega, Boniface K 3 ; Zhi-Zhong, Li 3 ; Shi, Tao 4 ; Ke-Fang, Ou 5 ; Yu-Ting, Liang 5 ; Jin-Ming, Chen 4 ; Xing-Yu, Yang 5 

 Chinese Academy of Sciences, CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Wuhan, China (GRID:grid.9227.e) (ISNI:0000000119573309); Chinese Academy of Sciences, Center of Conservation Biology, Core Botanical Gardens, Wuhan, China (GRID:grid.9227.e) (ISNI:0000000119573309); University of Chinese Academy of Sciences, Beijing, China (GRID:grid.410726.6) (ISNI:0000 0004 1797 8419); Ethiopian Biodiversity Institute, Addis Ababa, Ethiopia (GRID:grid.410726.6) 
 South-Central University for Nationalities, College of Life Science, Wuhan, China (GRID:grid.412692.a) (ISNI:0000 0000 9147 9053) 
 Chinese Academy of Sciences, CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Wuhan, China (GRID:grid.9227.e) (ISNI:0000000119573309); Chinese Academy of Sciences, Center of Conservation Biology, Core Botanical Gardens, Wuhan, China (GRID:grid.9227.e) (ISNI:0000000119573309); University of Chinese Academy of Sciences, Beijing, China (GRID:grid.410726.6) (ISNI:0000 0004 1797 8419) 
 Chinese Academy of Sciences, CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Wuhan, China (GRID:grid.9227.e) (ISNI:0000000119573309); Chinese Academy of Sciences, Center of Conservation Biology, Core Botanical Gardens, Wuhan, China (GRID:grid.9227.e) (ISNI:0000000119573309) 
 Wuhan Institute of Landscape Architecture, Wuhan, China (GRID:grid.9227.e) 
Publication year
2020
Publication date
Dec 2020
Publisher
Springer Nature B.V.
e-ISSN
19993110
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2403242340
Copyright
© The Author(s) 2020. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.