Correlation Between Soil Microorganism And Medicinal Secondary Metabolites Of Artemisia Annua L.

Artemisia annua L.,as a traditional medicinal plant,has a medical history of more than two thousand years.It has a variety of secondary metabolites,such as terpenoids,polyphenols,flavonoids and so on.A.annua is affected by various environmental factors,such as soil microorganism,light,nutrients,Water content,pH,enzymetic activity,etc.,these factors further affect the accumulation of its'secondary metabolites.Soil microorganism is an important component of soil ecosystem.It plays an important role in biological process of nutrient cycling and energy flow in soil ecosystem,between aboveground plant growth and underground microorganisms.To explore the relationships of soil microorganism on medicinal secondary metabolites,In this paper A.annua was used as the research materials to investigate the relationships between the accumulation of secondary metabolites and soil microorganism by analyzing the concentrations of secondary metabolites and the soil characteristics of A.annua in 54samples from 18 sites in Guiyang City(GY),Luodian County(LD),Sansui County(SS),Jianhe County(JH),Liping County(LP)and Suiyang County(SY).The results obtained were following:1.Soil physicochemical properties and enzymetic activity of A.annuaThe contents of organic matter(OM),nitrogen,phosphorus,potassium,Sucrase,urease and phosphatase activities in the soils greatly varied among all sample sites of A annua.,and the plant can grow in soils with different percentage of stone,indicating that A.annua is widely adaptable.The contents of soil OM and total potassium(TK)were higher,and the content of Available nitrogen(AN)is lower than other nutrients,and the soil pH is mostly neutral;The sucrase activity was higher,and the activity of urease and phosphatase is lower.Soil enzyme activity was related to soil physicochemical properties.Sucrase,urease and phosphatase activities were extremely significantly related to TK,soil soil moisture(SM)and Available nitrogen(AN)(P<0.01),and sucrase?urease were significantly related to OM(P<0.05).2.Soil microorganism of A.annua24 PLFAs were detected in A.annua soil of different sample sites,ane the soil microorganism biomass(SMB)(Total PLFA content)of soil was varied greatly,the dominsnt strain was bacterium.Judging by the total PLFAs contents of all kinds of microbes,the dominant trend was bacteria>fungi>actinomycetes>nematodes,respectively account for 87.92%,5.73%,5.26%and 0.55%of the total SMB.The content of SMB and the total bacteria PLFAs were relatively higher in GY,SS,LP and SY,and the content of JH3 and LD3 were lower.The highest Shannon indexes of soil microbial community composition was 2.10(GY1),and the lowest was1.26(JH3).The highest of evenness indexes was 0.66(GY1),the lowest was 0.40(JH3),and the highest of Simpson indexes was 0.83(LD2),the lowest was 0.55(JH3).Based on 24 PLFAs,soil microbial community composition was closely related to environmental factors.Through canonical correspondence analysis(CCA)and Mantel tests of Microbial community compositions with environmental factors,the partial correlations between altitude,soil pH?total phosphorus(TP)?AN(P=0.001),TK(P=0.009)and microbial PLFAs were extremely significant or significant.3.Content of Secondary metabolites of A.annuaThe contents of artemisinin?artemisinic acid?total polyphenols?scopoletin?chrysosplenol-D?chrysosplenetin were different among different sample sites.The level of the contents from high to low in turn was artemisinin,total polyphenols,scopoletin,chrysosplenetin,artemisinic acid,chrysosplenol-D.The content range of artemisinin was from 0.54 to 20.82 g/kg,the range of total polyphenols was from 2.99 to 8.29 g/kg,the range of scopoletin was from 0.41to 1.53 g/kg,the range of chrysosplenetin comcentrations was from 0.20 to 0.56 g/kg,the content range of artemisinic acid was from 0.02 to 0.47 g/kg,and the range of chrysosplenol-D was from0.08 to 0.33 g/kg.4.Correlation between Soil microorganism,environmental factors and secondary metabolites of A.annuaThe soil microorganism is related to the secondary metabolites of A.annua.The artemisinin were extremely significantly positively related to the fungi,actinmycetes and nematode respectively(P<0.01);The Artemisinin and chrysosplenol-D had extremely significantly negative connection with the G~-(P<0.01);The artemisinin was significantly positively related to the SMB(P<0.05);The artemisinic acid was significantly positively related to the actinmycetes(P<0.05);Total polyphenols were significantly negatively related to the actinmycetes and nematode(P<0.05);The scopoletin was significantly negatively related to the SMB and total bacteria(P<0.05);The chrysosplenetin were extremely significantly negatively related to the G~-and total bacteria(P<0.01).In addition,environmental factors also affected the contents of secondary metabolites of A.annua.The artemisinin was extremely significantly negatively related to the TN,TP and TK in the soil(P<0.01);The artemisinic acid was significantly related to the TP and pH(P<0.05);total polyphenols were extremely significantly positively related to the TN and TK(P<0.01);The scopoletin and chrysosplenetin were significantly or extremely significantly related to the TP and pH(P<0.05 or P<0.01);The chrysosplenol-D was extremely significantly negative related to the pH(P<0.01);The chrysosplenol-D and chrysosplenetin were significantly or extremely significantly positive related to the urease(P<0.05 or P<0.01).5.P-solubilizing capability of 3 inorganic phosphorus bacteria in soil of A.annua.Three inorganic P-solubilizing bacteria were selected from the A.annua soil,named as P1,P2 and P3.The growth rate from high to low in turn is:P2>P1>P3.The P-solubilizing capabilities were measured with inorganic phosphorus culture medium,and the P-solubilizing capability was P2>P1>P3.The growth rates(OD values)of 3 strains gradually increased with time increasing When cultured in organic phosphorous medium,while the pH decreased gradually,and the organic acids also changed.Morphological identification of the strains was made,then the16S r RNA of the phosphorus bacteria was sequenced and the Retrieving homologous sequences was done by BLAST and phylogenetic tree were constructed.Combined with the above results,three strains were identified as Acinetobacter sp..