Wang Hui-Zhong, Wu Zhen-Xing, Lu Jiang-Jie, Shi Nong-Nong, Zhao Yan, Zhang Zhi-Tao, Liu Jun-Jun
Key Laboratory of Biochemistry and Molecular Biology, Hangzhou Normal University, Hangzhou, China.
Genetica. 2009 Jul;136(3):391-9. doi: 10.1007/s10709-008-9340-0. Epub 2008 Dec 17.
Spring orchid (Cymbidium goeringii) is a popular flowering plant species. There have been few molecular studies of the genetic diversity and conservation genetics on this species. An assessment of the level of genetic diversity in cultivated spring orchid would facilitate development of the future germplasm conservation for cultivar improvement. In the present study, DNA markers of intersimple sequence repeats (ISSR) were identified and the ISSR fingerprinting technique was used to evaluate genetic diversity in C. goeringii cultivars. Twenty-five ISSR primers were selected to produce a total of 224 ISSR loci for evaluation of the genetic diversity. A wide genetic variation was found in the 50 tested cultivars with Nei's gene diversity (H = 0.2241) and 93.75% of polymorphic loci. Fifty cultivars were unequivocally distinguished based on ISSR fingerprinting. Cultivar-specific ISSR markers were identified in seven of 50 tested cultivars. Unweighted pair-group mean analysis (UPGMA) and principal coordinates analysis (PCA) grouped them into two clusters: one composed the cultivars mainly from Japan, and the other contained three major subclusters mainly from China. Two Chinese subclusters were generally consistent with horticultural classification, and the third Chinese subcluster contained cultivars from various horticultural groups. Our results suggest that the ISSR technique provides a powerful tool for cultivar identification and establishment of genetic relationships of cultivars in C. goeringii.
春兰（Cymbidium goeringii）是一种广受欢迎的开花植物物种。关于该物种的遗传多样性和保护遗传学的分子研究较少。评估栽培春兰的遗传多样性水平将有助于未来为品种改良进行种质保护。在本研究中，鉴定了简单序列重复区间（ISSR）的DNA标记，并使用ISSR指纹技术评估春兰品种的遗传多样性。选择了25个ISSR引物，共产生224个ISSR位点用于遗传多样性评估。在50个测试品种中发现了广泛的遗传变异，Nei氏基因多样性（H = 0.2241），多态性位点占93.75%。基于ISSR指纹图谱明确区分了50个品种。在50个测试品种中的7个中鉴定出了品种特异性ISSR标记。非加权组平均分析（UPGMA）和主坐标分析（PCA）将它们分为两个聚类：一个聚类主要由来自日本的品种组成，另一个聚类包含三个主要亚聚类，主要来自中国。两个中国亚聚类总体上与园艺分类一致，第三个中国亚聚类包含来自不同园艺组的品种。我们的结果表明，ISSR技术为春兰品种鉴定和品种间遗传关系的建立提供了一个强大的工具。
