Development of a Molecular Marker to Identify a Candidate Line of Turmeric (Curcuma longa L.) with a High Curcumin Content

Abstract

Dried and fresh rhizomes of the spice turmeric (Curcuma longa L.) are well known in traditional medicine, and curcu- min is widely used in various geographic regions. Although there are differences in the amount of curcumin within this species, identification of the candidate line by rhizome is difficult because of the relative simplicity of its morphological characteristics. To accurately identify lines of C. longa with a high content of curcumin, we analysed several sequences of chloroplast DNA. First, to determine the appropriate outgroup taxa in which to conduct infras-pecific analyses of C. longa, we reconstructed the molecular phylogenetic tree of C. longa and its allied species. The results showed that C. aromatica and C. zedoaria are closely related to C. longa. Next, to develop a molecular marker for identifying lines of C. longa with a high content of curcumin, a network analysis using chloroplast microsatellite regions was performed. Results showed that a unique haplotype within C. longa corresponds to the high curcumin content line. Therefore, the chloroplast microsatellite regions used for the analysis allowed us to determine the lines of this species with high cur- cumin content.