Gastrodia tuber and its component gastrodin have many pharmacological effects. The chemical fingerprints and gastrodin contents of eight Gastrodia populations were determined, and the genomic DNA polymorphism of the populations was investigated. Genetic distance coefficients among the populations were calculated using the DNA polymorphism data. A dendrogram of the genetic similarities between the populations was constructed using the genetic distance coefficients. The results indicated that the genomic DNA of Gastrodia tubers was highly polymorphic; the eight populations clustered into three major groups, and the gastrodin content varied greatly among these groups. There were obvious correlations among genetic makeup, gastrodin content, and place of origin. The ecological environments in Guizhou and Shanxi may be conducive to evolution and to gastrodin biosynthesis, and more suitable for cultivation of Gastrodia tubers. These findings may provide a scientific basis for overall genetic resource management and for the selection of locations for cultivating Gastrodia tubers.

The Gastrodia tuber, as well as the gastrodine extract derived from it, has been found to have many pharmacological effects. The gastrodine content of different tuber populations was determined, and their genomic DNA fingerprints were investigated. Through recovery, cloning, sequencing and bioinformatics analyses of DNA fragments, five DNA sequences were proved to be new discoveries. Using the PCR technique, we further studied the distribution of the sequences in eight Gastrodia populations, as well as their correlation with gastrodine content. The distribution of the five DNA sequences varied greatly among the populations. DNA sequences 1 and 5 were found in all the populations studied and determined to be specific DNA molecular markers that differentiate Gastrodia from other species. DNA sequence 2 was found only in the populations showing the highest gastrodine content. Hence, these sequences can be applied to identify genuine Gastrodia tubers and to optimise the selection of better populations.