Agronomic Characters And Chemical Contents Analysis Of Artemisia Annua L.

Artemisia annua L.is a traditional herbal medicine used since two thousand years ago in China.Artemisin distilled from A.annua is a new drug with the highest efficiency and lowest toxicity in treating malarial.Nowadays,the only source of artemisinin still comes from the extraction of A.annua.But,at present,the content of artemisin in A.annua is very low rifely and the trace amount of artemisinin in wild A.annua is a bottleneck to meet the urgent need at the maximum extent for malaria therapy.And the essential oil of A.annua has the functions of clearing heat,cooling the blood and allaying a fever,et al..A.annua resources wildly distributs in Sichuan Province.In recents years,A.annua were introduced and cultivated in Sichuan Province by many enterprises.This study determined the contents of artemisinin and essential oil by HPLC and GC/MS,and measured the main agronomic characters of A.annua resources wildly growing and introduced in Sichuan Province,in order to provide some scientific proofs to breed the high yield and Artemisinin content of A.annua.The main results were summarized as follows:1.The wild and introduced A.annua differed significantly in the following charactors, such as plant height,the yield per plant,the weight of dried stem per plant,the angle of the divarication,the number of primary branches,the diameter of stem,the bud dates,the first flowering dates and the florescence dates.They also significantly differed in the artemisinin percentage contents.Accession L06-45 had the highest yield per plant(0.23 kg per plant).Accession L06-32 was the top in the artemisinin percentage contents,which can reach 0.762%;The following was Huanghuahao 2.While L06-45 have the highest artemisinin contents per plant(1.29 per plant).2.There were no significant difference on yields of per plant between Sichuan wild resources and the introduced A.annua.The artemisinin content was generally lower in wild A.annua,but the introduced cultivar still had higher artemisinin content after cultivation in Sichuan.So Sichuan Province can be the promoting area for a number of excellent varieties of A.annua.The test also indicated that,the artemisinin content of purple-stem A.annua was significantly higher than that of dark green-stem A.annua.3.It was showed that the main agronomic characters had positive correlation with the yield per plant,and the weight of dried stem per plant had extremely significant positive correlation with the yield per plant,the coefficient of correlation is 0.9284,and number of primary branches and the diameter of stem with the yield per plant were positively significantly correlation.The main agronomic characters had positive correlation with the total artemisinin content per plant except for the angle of the divarication.And that the florescence had extremely significant positive correlation with the yield per plant and the total artemisinin content per plant,That is to say,the A.annua with the late florescence dates are usually higher in the artemisinin percentage contents and the artemisinin contents, which is the guide for breeding A.annua from florescence dates aspect.4.Through the multiple regression analysis of the main agronomic characters with the yield per plant and the artemisinin percentage contents and the total artemisinin content per plant,it was showed that plant height,the bud dates,florescence were the key factors to affect the yield per plant among various after anglicizing their relationships with the yield per plant according to the multiple regression equation Y=0.061 21-0.000 08X₁+0.303 78X₃-0.000 51X₄-0.000 31X₅.That plant height,the bud dates,florescence were the key factors to affect the artemisinin percentage content among various after anglicizing their relationships with the artemisinin percentage contents.The classic multiple regression equation of the artemisinin percentage content was Y=-1.458 49-0.000 99X₁-0.240 79X₃+0.133 62X₆-0.007 19X₇+0.014 54X₉.The plant height,the weight of dried stem per plant,the diameter of stem and florescence were the key factors to affect the yield per plant among various after anglicizing their relationships with the yield per plant,the classic multiple regression equation of the total artemisinin content per plant was Y=-2.670 01-0.002 49X₁+0.988 73X₃+0.300 37X₆+0.011 13X₉.5.The results showed that breeding new varieties of A.annua high in yield and the artemisinin percentage contents should focus on those materials with the proper branches numbers and the plant height,as well as with the smaller angle of divarication.To cater to the profits of the farmer and the enterprise,when we breed new varieties of A.annua,we should mainly focus on the artemisinin percentage contents,and at the same time consider the yielding characters,focusing on the higher plant with the rough and purple stems, proper branches and florescence dates,and the smaller angle of divarication.6.Fifty-five chemical constituents were identified from 41 A.annua accessions.And according chemical structure and character of those constituents,compartmentalize 19 Monoterpene,22 Sesquiterpene,13 Non-terpenoids and 1Diterpene.The average coments of ten chemical components were higher in those resources,includingβ-Cubebene, D-(+)-Camphor,β-Caryophyllen,β-Farnesene,Eudesma-4(14),11-diene,Eucalyptol, Artemisia ketone,Camphene,Borneol and z-Elemene.β-Cubebene,D-(+)-Camphor,β-Caryophyllen,β-Farnesene and z-Elemene are the common contents in all of the volatile oils.7.The result of cluster analysis of the contents of volatile oil showed that 55 A.aunnu accessions could be divided into 5 chemical types based on that the similarity coefficient 0.17.The five chemotypes related to the color of stem and the shape of leaves,and had little relationships with the geographical distribution.According to the contents of monoterpene and sesquiterpene in 41 accessions,the chemotype of A.annua could be concluded into three types.They were sesquiterpene-rich type with sesquiterpene more than 85%,mid-type with the proportion of sesquiterpene/monoterpene 3:1,and the monoterpene-sesquiterpene type was 1:1.8.The study also showed that the artemisinin percentage content had some relationships with the volatile oil contents.The accessions with more monoterpene in essential oils usually had higher artemisinin percentage contents,and that had more sesquiterpene often had lower artemisinin percentage contents.The artemisinin percentage contents from low to high in order were sesquiterpene-rich type＜mid-type＜monoterpene-sesquiterpene type.