Comparison of the genetic diversity in two species of cycads
Longqian Xiao A B , Xun Gong A D , Gang Hao C , Xuejun Ge C , Bo Tian A and Sixiang Zheng BA Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, P.R. China.
B Yunnan Agriculture University, Kunming 650201, P.R. China.
C South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, P.R. China.
D Corresponding author. Email: gongxun@mail.kib.ac.cn
Australian Journal of Botany 53(3) 219-223 https://doi.org/10.1071/BT04052
Submitted: 20 April 2004 Accepted: 23 December 2004 Published: 26 May 2005
Abstract
Inter-simple sequence repeat (ISSR) markers were used to examine the level and distribution of genetic diversity in two cycad species: Cycas parvula S.L.Yang and C. balansae Warburg. The former is found in only two adjacent populations and the latter in a relatively wider distribution. Although genetic diversity in C. balansae (He = 0.1301) is higher than that in C. parvula (He = 0.0538), both are still low in comparison with the mean value (He = 0.169) in gymnosperms. This confirms the general opinion that cycads are genetic relics. The genetic differentiation in both species, however, presents a striking contrast: Gst is 0.0978 in C. parvula, but 0.4003 in C. balansae, which may be ascribed to the difference in distances between their populations.
Acknowledgments
This work is supported by the National Natural Science Foundation of China (No. 30070081). The manuscript was much improved by comments and suggestions from two anonymous reviewers.
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