Tree Genetics & Genomes

, 12:111 | Cite as

Genetic diversity and population structure of common walnut (Juglans regia) in China based on EST-SSRs and the nuclear gene phenylalanine ammonia-lyase (PAL)

  • Huan Han
  • Keith E. Woeste
  • Yiheng Hu
  • Meng Dang
  • Tian Zhang
  • Xiao-Xiao Gao
  • Huijuan Zhou
  • Xiaojia Feng
  • Guifang Zhao
  • Peng ZhaoEmail author
Original Article
Part of the following topical collections:
  1. Germplasm Diversity


Common walnut (Juglans regia L.) is an economically important temperate tree species valued for both its nut and wood. We investigated the genetic diversity and population structure of J. regia germplasm from 13 locations in China using 10 markers derived from expressed sequences (EST-SSR) and sequence polymorphisms within the phenylalanine ammonia-lyase (PAL) gene. Analysis of the population genetic structure based on EST-SSRs showed distinct populations in northern versus southern China that were not reflected in the spatial distribution of PAL haplotypes. High levels of population differentiation were probably the result of reproductive isolation and in southern China, hybridization with Juglans sigillata. The results indicate the possible presence of distinct evolutionary lineages of J. regia in the Qinling and Daba Mountains of China and in Yunnan province that may require ecological management if they are to be retained as in situ resources.


Qinling-Daba MountainsPersian walnutGenetic structureJuglans sigillataMicrosatellites 



The authors wish to thank Jia Yang, Li Feng, and Tao Zhou for sample collection. This work was supported by the National Natural Science Foundation of China (nos. 41471038, 31200500, J1210063), the Program for Excellent Young Academic Backbones funding by Northwest University (no. 338050070), the Northwest University Training Programs of Innovation and Entrepreneurship for Undergraduates (nos. 2015159 and 2016171), Changjiang Scholars and Innovative Research Team in University (no. IRT1174). Mention of a trademark, proprietary product, or vendor does not constitute a guarantee or warranty of the product by the U.S. Department of Agriculture and does not imply its approval to the exclusion of other products or vendors that also may be suitable.

Data archiving statement

The different haplotypes of amino acid positions based on sequence of Jr5680 was submitted on the National Center for Biotechnology Information (NCBI), the accession numbers were: KT820730, KT820731, KT820732, KT820733. The Unigene sequences and BLAST search results for 11 SSR-containing ESTs were provided as Supplementary Table S2. The total unigene sequence of Jr5680 was provided as Supplementary Table S4.

Supplementary material

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Table S6 (DOC 29 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Huan Han
    • 1
  • Keith E. Woeste
    • 2
  • Yiheng Hu
    • 1
  • Meng Dang
    • 1
  • Tian Zhang
    • 1
  • Xiao-Xiao Gao
    • 1
  • Huijuan Zhou
    • 1
  • Xiaojia Feng
    • 1
  • Guifang Zhao
    • 1
  • Peng Zhao
    • 1
    Email author
  1. 1.Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life SciencesNorthwest UniversityXi’anChina
  2. 2.USDA Forest Service Hardwood Tree Improvement and Regeneration Center (HTIRC), Department of Forestry and Natural ResourcesPurdue UniversityWest LafayetteUSA

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