干旱区生态环境知识资源中心

Wild Licorice (Glycyrrhiza uralensis) is important medical plant. It is distributed in the Asia, especially in the semi-arid zone of China and Mongolia. However wild Licorice contains the high quality of glycyrrhizin (GL), which is the active ingredient holding in the root, the cultivated Licorice in China and Japan contains it low.

The objective of this study is to establish the cultivating method of the high quality Licorice. First, field investigation of the high quality Licorice was conducted at semi-arid area of the South Mongolia in May 2010. There were many large and high quality Licorices in South Mongolia. The average low and high temperature in winter was very low.

Second, to clear the soil properties at the area of growing wild Licorice, soil physical and chemical experiment were conducted. All of soil textures were ’sand’, and the saturated and unsaturated hydraulic conductivities showed well drainage and the available moistures were little. The concentrations of Ca in south Mongolia was high, that value was 111.0 mg/100 g.

Third, the plastic tube cultivation experiments to evaluate the effects of increasing GL in Licorice by applying Ca2+ ion and low temperature as an environmental stress were conducted. In the cultivation experiment, applying Ca2+ ion made GL of Licorice increased a little. On the other hand, The concentration of GL in Licorice applied the low temperature for 7 days increased twice than growing at 20 degrees C constant conditions, although the root diameter was almost equal.

These results will contribute in the semi-arid area growing wild Licorice because the soil properties growing high quality Licorice was clarified. It is considered that environmental stresses, especially low temperature, were effective to increase GL in Licorice.