Prediction Of Potential Distribution Area Of Coptis Chinensis Franch.and Analysis Of Key Environmental Factors Affecting Its Quality Formation

Coptis chinensis Franch.,a medicinal plant,belongs to the genus Coptis in Ranunculaceae,and its rhizomes are main medicinal part.C.chinensis,wild or cultivated,mainly distributes in Sichuan,Chongqing,Hubei,Hunan,Shaanxi and other places.The main active ingredient of C.chinensis is the alkaloid.Most of the previous studies are related to the pharmacological activity and the content of chemical components.Due to its huge economic value and wide range of uses,the resources of C.chinensis from different geographic source have been destroyed by humans for a long time.With global climate changes,the natural habitat of C.chinensis has been severely degraded,which has caused significant changes in the distribution pattern of C.chinensis.Existing C.chinensis is mostly artificially cultivated with small population size,making its resources increasingly endangered.In this study,the potential geographic distribution of C.chinensis was predicted based on the Max Ent model(Maximum Entropy modeling).And the potential distribution area was classified into four grades,and then samples of C.chinensis in different grades of suitable areas were collected.High performance liquid chromatography(HPLC)was used to detect the content of six alkaloids from these samples.We explored the correlation between the content of active ingredients and habitat suitability,selected the environmental factor with the greatest contribution in the prediction model to conduct stress experiments on the samples of C.chinensis and used real-time quantitative PCR(q RT-PCR)to detect the expression levels of key genes for the quality formation of C.chinensis under different stress conditions,to explore the influence of environmental factors on the quality formation of C.chinensis.The main findings are as follows:(1)A total of 99 records of C.chinensis were used to construct the prediction model.The AUC value of the model operation result is greater than 0.9,indicating that the model has high predictive ability and the prediction results are highly reliable.The prediction results showed that C.chinensis is mainly distributed in Sichuan,Hunan,Hubei,Shaanxi,Guizhou and Chongqing.And the two climatic factors,the average temperature difference and the coldest season precipitation,contributed the most to the model prediction.And the total,highly,and moderately suitable areas of C.chinensis decrease significantly in the future;(2)The HPLC results indicated that the samples of C.chinensis in different grades of suitable areas contain six kinds of alkaloids,and the alkaloid content of samples collected from the highly suitable areas was the highest,followed by moderate and general suitable areas.The content of active components in C.chinensis decreased according to the grade of suitable area.Temperature difference between day and night,rainfall in the coldest season,annual rainfall and altitude all have a significant positive correlation with the total alkaloid content of C.chinensis.(3)Key environmental factors were used to conduct stress tests on C.chinensis,and the expression levels of key genes for quality formation of C.chinensis were analyzed under different stress conditions.The results indicated that temperature difference between day and night may increase the synthesis and accumulation of berberine by inducing the expression of this key genes.And proper water deficit may increase the synthesis and accumulation of the effective components of C.chinensis by inducing high expression of Cchi078208.m1 and Cchi013467.m1.Based on the comprehensive analysis,the current potential distribution areas of C.chinensis are Sichuan,Hunan,Hubei,Shaanxi,Guizhou and Chongqing.Under the condition of climate change,the future potential distribution areas of C.chinensis will decrease significantly.The temperature difference between day and night and precipitation in the coldest season contributed the most to the model,which were the key environmental factors affecting the distribution of C.chinensis.And the key environmental factors could affect the quality formation of C.chinensis through different regulatory effects on key genes in the alkaloid biosynthesis pathway.