4. Discussion
4.1. The classification of spring orchid variants
There has been much discussion on the botanical classification of Orchidaceae due to the large number of cultivars with tremendously varied morphological traits. C. goeringiivar. longibracteatum have been classified previously as variants of spring orchid as early as 1980 ( Wu and Chen, 1980). However, further AFLP analysis of the relationship between cultivars contained in C. goeringii var. longibracteatum showed that they were quite distant from spring orchid ( Chen and Liu, 2003). The results of the clustered analysis obtained in this study, based on the EST-SSR allelic data of 129 spring orchid cultivars, provided evidence that the cultivars in this variant have a quite close relationship with other cultivars from C. goeringii ( Fig. 1). Similarly, although cultivars from C. goeringii var. tortisepalum clustered together in a clade they were also mixed together with cultivars from C. goeringii ( Fig. 1). Furthermore, results of studies on the genetic diversity of Yunnan Orchidaceae with RAPD techniques were consistent with our EST-SSR analysis, as C. goeringii var. serratum was clustered into the same group withC. goeringii ( Cheng et al., 2006). Taken together, all cultivars from three C. goeringiivariants were mixed together with some cultivars from C. goeringii in subgroup A1 ( Fig. 1). Therefore, it can be suggested that the establishment of these variants is not genetically supported. The taxonomy of spring orchid, especially previously recognized variants, therefore, needs further study