American Journal of Plant Sciences, 2014, 5, 3194-3202 Published Online October 2014 in SciRes. http://www.scirp.org/journal/ajps http://dx.doi.org/10.4236/ajps.2014.521335 Genetic Diversity and Population Structure of North China Mountain Walnut Revealed by ISSR Aiqing Ji1,2, Yina Wang1, Guoliang Wu1*, Wenjiang Wu3, Hongyan Yang4, Qihai Wang1 1College of Horticultural Science, Henan Agricultural University, Zhengzhou, China 2Department of Biology Science Technology, Jinzhong College, Jinzhong, China 3Department of Food Science and Technology, Henan Agricultural University, Zhengzhou, China 4Jinzhong Meteorological Bureau, Jinzhong, China Email: *
[email protected] Received 18 August 2014; revised 21 September 2014; accepted 17 October 2014 Copyright © 2014 by authors and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/ Abstract North China Mountain Walnut (NCMW) is one of the ancestors of extant cultivated species, and a valuable gene resource for resistance breeding of walnut in China. Inter-Simple Sequence Repeat (ISSR) primers were designed to evaluate the level and pattern of genetic diversity in eight popu- lations of NCMW. Nine ISSR primers yielded 91 amplification products with different sizes, of which 84 (92.31%) were polymorphic. A high species-level genetic diversity was detected with Nei’s (H = 0.2592) and Shannon’s diversity (I = 0.4003). In contrast, the population-level genetic diversity was relatively lower (PPB = 43.27%, H = 0.1347, I = 0.1862). Coefficient of populations differentiation (GST) was 0.5066, indicating that inter-population and intra-population variation contributed 50.66% and 49.34% respectively to the total genetic variability.