The origin and germplasm collection for cultivated Dendrobium officinale K. Kimura & Migo individuals revealed by EST-SSR markers

摘要

Dendrobium officinale K. Kimura et Migo is an endangered and valuable medicinal herb. In order to understand the origin of D. officinale cultivars and the differences in germplasm resources, 81 D. officinale individuals including wild-collected, market-collected, and two germplasm resources from Zhejiang and Jiangxi province was scanned with 75 EST-SSRs. The number of alleles detected at each locus ranged from 1 to 14 with an average of 3.703. The mean expected heterozygosity (0.492), and Shannon's information index (0.915) indicated a high level of hybridization rate among the individuals tested. Principal component analysis and cluster analysis based on UPGMA illustrated that almost all the germplasm resources from Jiangxi were grouped together, then the germplasm resources from Zhejiang, wild-collected and market-collected were divided into three clusters, indicated that the origin of market-collected individuals were derived from Zhejiang and the germplasm resources from Jiangxi were well preserved and waited for development. Eight recovered sequences of fructose-bisphosphate aldolase 1 from wild-collected and two germplasm resources showed that the similarity of these sequences ranged from 71.15 to 93.42%, and base insertion, deletion and base varieties occurred in almost all the 7 recovered sequences. On the basis of EST-SSR analysis and keeping in view the purity and stability, the D. officinale germplasm resources from Jiangxi was recommended for hybridization in order to develop superior cultivars.