Effects of Climatic Factors on Contents of Major Medical Components in Smilax china from Different Regions in Western Hunan

To study the impact of climatic factors on the major medical component in Smilax china, and to supply a scientific and standard operation protocol on the introduction and cultivation.Detect the content of major medical components, such as baicalin and astibin, in Smilax china from eight counties of Xiangxi Autonomous Prefecture. And establish their relationship with annual average temperature, Jan average temp, Jul average temp, valid accumulative temp (≥ 10 degress C), annual maximum temp, annual minimum temp, annual precipitation, annual sunshine amount, non-frost period and relative humidity by using the methods of partial least squares regression analysis (PLS).Relative humidity, annual minimum temp and annual precipitation are the dominant factors. Annual minimum temp, annual average temp and valid accumulative temp were significantly correlated to the content of major medical components, thus, relative humidity, annual precipitation and non-frost period were negatively related to them.This study provides a scientific basis for resources protection,introduction and cultivation of Smilax china.