Effect of Gibberellic Acid and Chlormequat Chloride on Growth, Coumarin Content and Root Yield of Angelica dahurica var. Formosana

The effects of the plant growth promoter gibberellic acid (ga3) and plant growth retardant chlormequat chloride (ccc) on biomass and quality of angelica dahurica var. formosana plants were investigated employing physiological and biochemical methods. plants were sprayed with ga3 or ccc at rosette stage and coumarin content was analyzed by high performance liquid chromatography (hplc) after harvest. two coumarins in root were detected: isoimperatorin and imperatorin. the root content of imperatorin was not affected by application either ga3 or ccc, while isoimperatorin was increased to 127% after treatment with ccc (400 mg l-1). the lowest concentrations of ga3 (50 mg l^-1) and ccc (400 mg l^-1) increased root yield to 157 and 139%, respectively. we note here that ga3 and ccc might be used in improving the yield of a. dahurica var. formosana and maintaining the coumarin content.