Adaptability Analysis Of Medicinal Plants Based On Photosynthetic Characteristics

On account of the different climate,soil and so on,the content of effective constituent is not same,which come from the same kind of herb but different areas.The purpose of this study is to explore the relationship between photosynthetic characteristics of medicinal plants and their adaptability to light conditions.The study mainly determined light response curves of 51 herbs.Plants are classified in suitable growth environment by light saturation point or maximum photosynthetic rate.The main results are as follows:The main China provinces are divided into 4 categories by different sunshine duration data through Cluster analysis.Sunshine hours are more than 2700 hours,2300 to 2500 hours,1700 to 2100 hours,and less than 1600 hours respectively.The herbal 51 kinds according to the light saturation point is divided into 3 groups,The light saturation point is more than1500μmol·m^-2·s^-1,1000 to 1500μmol·m^-2·s^-1,and less than 1000μmol·m^-2·s^-1,respectively.According to the distribution area of medicinal plants,analyze the photoperiod of the corresponding areas where three groups of medicinal plants grow.Without considering precipitation,temperature and other factors,medicinal plants with LSP>1500μmol·m^-2·s^-11 can adapt to the sunshine hours greater than 2300h,and LSP at 1000-1500μmol·m^-2·s^-1.The medicinal plants can adapt to the sunshine hours in the area of 1700-2500h,and the medicinal plants with LSP<1000μmol·m^-2·s^-11 can adapt to the areas with the sunshine hours less than1600h.The maximum photosynthetic rate of herbs have been computed,and the change rate of maximum photosynthetic rate in 600μmol·m^-2·s^-11 and 2000μmol·m^-2·s^-1.Based on the research of medicinal materials of suitable growth conditions,the herbs is divided into two groups in tolerance to shade according to changes in the maximum photosynthetic rate.When the photosynthetic effective radiation is 600μmol·m^-2·s^-1,the medicinal plants whose net photosynthetic rate decrease below 15%have good adaptability to shading,and the plants whose photosynthetic rate decrease more than 15%doesn’t like shade;When the photosynthetic effective radiation is 2000μmol·m^-2·s^-1,Plants with significant inhibition of net photosynthetic rate should not be planted in open field,and plants with no significant changes in photosynthetic rate（<10%）have a certain ability to adapt to full sunlight.This study provides reference for the standardized cultivation of medicinal plants in theory,and provides a theoretical basis for the introduction and cultivation of medicinal plants and the selection of medicinal plant species grown under the forest.