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Australian Journal of Botany Australian Journal of Botany Society
Southern hemisphere botanical ecosystems
RESEARCH ARTICLE

Genetic structure of the endangered, relict shrub Amygdalus mongolica (Rosaceae) in arid northwest China

Song Mei Ma A G H , Ying Bin Nie B H , Xiao Long Jiang C D , Zhe Xu E and Wan Quan Ji F G
+ Author Affiliations
- Author Affiliations

A College of Science, Shihezi University, Shihezi 832000, Xinjiang, China.

B Institute of Crop Research, Xinjiang Academy of Agri-Reclamation Sciences, Shihezi 832000, Xinjiang, China.

C Shanghai Key Laboratory of Plant Functional Genomics and Resources, Shanghai Chenshan Botanical Garden, Shanghai 201602, China.

D Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Shanghai 201602, China.

E The Key Laboratory of Biogeography and Bioresource in Arid Land, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China.

F State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy (Northwest A&F University), Yangling 712100, China.

G Corresponding authors. Email: shzmsm@126.com; jiwanquan2008@126.com

H *These author contributed equally to this work.

Australian Journal of Botany 67(2) 128-139 https://doi.org/10.1071/BT18188
Submitted: 5 October 2018  Accepted: 18 March 2019   Published: 3 May 2019

Abstract

In the present study we selected the endangered species Amygdalus mongolica to investigate the influence of climatic fluctuations on the spatial genetic patterns and evolutionary history of organisms in arid northwest China. The intraspecific genetic variation and demographic history of A. mongolica were investigated using two cpDNA sequences (psbK-psbI and trnL-trnF) from 174 individuals in 15 populations across most of its covered range. Significant genetic differentiation among populations was identified, which resulted from fragmented populations coupled with the enhanced aridification and desertification of the Pleistocene. Twelve haplotypes clustered into two clades, corresponding to the Western region (northernmost Gansu, Hexi Corridor and Alxa Left Banner) and the Eastern region (Urad Houqi, Yinshan Mountains, Urad Zhongqi and Daqing Mountains) respectively. Five independent Pleistocene refugia in different mountainous areas were identified. Amygdalus mongolica has likely experienced westward shifts from refugia along the margins of the Ulanbuhe and Tengger deserts, and also postglacial re-colonisation northward along the Hexi Corridor.

Additional keywords: demography, genetic differentiation, refugia.


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