Effects Of Shading On Physiological,Ecological Characteristics And Pharmacodynamic Components Of Epimedium Koreanum Nakai

E.koreanum is a perennial herb of Berberidaceae.Its dried leaves are used as medicine and it is a traditional Chinese replenishing type of traditional Chinese medicine.At present,the wild resources have been shrinking due to longterm excessive utilization.The artificial cultivation of E.koreanum is an effective way to relieve the pressure on wild resources.Related studies have pointed out that the ecological environment in the producing areas affects the quality of E.koreanum,but studies on the effects of the ecological environment,especially light conditions,on the growth and medicinal quality of E.koreanum are not yet in-depth.In this study,we used artificial introduction and cultivation of E.koreanum as the experimental material to study the growth and development,photosynthetic characteristics,protective enzyme activities,and active ingredient content of E.koreanum under different light intensities,revealing the light intensity of E.koreanum yield and The influence of medicinal materials quality provides a theoretical basis for large-scale artificial cultivation and quality control of E.koreanum.The main findings are as follows:1.From April to July,E.koreanum grew faster under different light intensities,and grew slowly after July.With the decrease of light intensity,the specific leaf area of E.koreanum increased,the leaves became thin,and the area of photosynthetic leaves increased.The aboveground weight,dry weight,and dry weight of E.koreanum were significantly affected by the light intensity.The fresh weight and dry weight reached the best when the light transmittance was 70% in August,It is 6.11 g,2.99 g,higher yield can be obtained under this condition.2.With the decrease of light intensity,the chlorophyll content of E.koreanum leaves increased,and the chlorophyll content of shade-treated leaves was significantly higher than that of full-illumination.The Ci contents of E.koreanum decreased with the increase of light intensity,and Pn decreased.Under strong illumination,strong light,large stomatal conductance,and high transpiration rate cause large water loss and poor growth.The results showed that under shading conditions,the growth and photosynthetic properties of E.koreanum are better overall.Moderate shading is beneficial to increase the photosynthesis of E.koreanum and is beneficial to its growth and development.3.From June to July,the qN at 70% light transmission was significantly higher than that at other treatments,while it was significantly higher than 70% and 100% at 70% and 30% light transmittance from July to August.The total light treatment of qP and Yeild was significantly lower than other treatments,and qN was also lower under full light treatment.It shows that the PS II reaction center under full light treatment is less open,the light energy absorbed by PS II and used for photosynthesis is also less,and the PS II function is poor under this treatment,which may also be plant growth under full light treatment.4.The activity of SOD,POD,and CAT in E.koreanum was significantly increased with light transmittance,the protective enzyme change trend is basically the same,The three enzyme synergies remove oxygen free radicals from the plant to maintain its homeostatic oxygen balance.It was shown that proper light intensity can increase the activity of antioxidant enzymes in E.koreanum and reduce MDA content,which is beneficial to the protection of E.koreanum cells and promote their growth.5.The contents of each active ingredient of E.koreanum varied significantly under different light intensities.When the light transmittance was 70%,the content of each active ingredient was the highest and higher than the 2015 version of the Chinese Pharmacopoeia standard.The content of epimedin A and epimedin C was the highest in June 15,and the content of epimedin B,icariin and total flavonoids was the highest around August 15.It shows that proper light intensity and harvest time can obtain high quality E.koreanum.6.Significant or extremely significant positive correlations between growth indicators and Gs and Pn under different light intensities.There was a significant positive correlation or extremely significant positive correlation between the growth index of E.koreanum and SOD,POD,CAT activity and MDA content at 50% and 30% light transmittance.There is a complex interrelationship between the growth and development of Epimedium koreanum and ecological factors and its physiological factors.