Studies On Breeding Of Excellent Variety Of Wild Artemisia Annua From Different Areas

Artemisinin,a kind of anti-malaria monomer and high efficient anti-malaria medicine with excellent curative effect for schistosomiasis and AIDES complication,was firstly separated from Artemisia cnnuaa L,a traditional Chinese medicine,in 1970s.The only source of artemisinin at present comes from the extraction of natural A.annua.Nowadays,A.annua cultivar is directly introduced and domesticated from wild A.annua,so the content of artemisinin is low.Owing to the discrepancy of gentic,the contents of artemisinin in simple Artemisinin are different.Understanding the biological characteristics of A.annua is the basement of choosing excellent variety as well as achievement of high yield.Economic benefit will be greatly increased through cultivation of A.annua cultivar with high and stable artemisinin content.In this dissertation.At first,.The research detected the content of A.annua in the laboratory,in order to supply the testing of selective evidence during the time of inheritance and breeding.After that,the biological characteristics and the heredity diversity of artemisinin content are studied for A.annua introduction and domestication, high yield cultivation as well as for high artemisinin content breeding,then artemisinin content variation at different growing stage and in different level branches at each stage is studied to determine the optimal harvest time as well as the optimal sampling time in A.annua breeding.In the end,the relationship between artemisinin content and A.annua morphology and structure is studied to provide simple,accurate and quick selecting criteria for breeding.The main results are as follows:1 After transforming the alkaloid,the research detecte the special peak of Ultraviolet Spectrum, the result isλ_max=292nm.Owing to analysing all kinds methods of detecting A.annua.the thesis validate the methods of detecting A.annua.The results show:By using of Ultraviolet Spectrophotometry to detect the content of A.annua,It's very simpleness and veracity,while the concentration of NaOH should be dominated the range of0.2%±0.02%,or the Absorbency of Q₂₉₂is low as well as unexact of the results.2 The seeds of A.annua have no dormancy,and can germinate when being sowed in the spring, summer or fall.The growth rate in the early seedling stage is slow.The seedlings can endure cold and smoothly pass the winter.The growth duration is different among A.annua comning from different origin.The A.annua from Xiushan district has the shortest growth duration and that from Youyang district longest and that from Zigong district sets between them.The yield and artemisinia content of A.annua introduced from Youyang district are higher.There is direct relationship Between leaf yield and growth duration,and the longer the growth duration the higher the leaf yield.3 A.annua is allogamous plant and artemisinin content varies greatly among single plants.The coefficient of differentiation of A.annua originated from Xiushan,Zigong and Youyang is 34.3%,36.9%and 38.6%respectively.The lines are obtained by selecting seeds of high artemisinin content single plants among the complex colony.The average artemisinin content and the percentage of single plants having high artemisinin content increase gradually year by year,and coefficient of differentiation of artemisinin content among single plants decreases yearly.Through selection of two generations the average artemisinin content of A.annua originated from Xiushan increases by 18.14%and by 10.13%that from Youyang,and percentage of single plants of high and second high artemisinin content increase from 8.0%,22.0%to 11.1%,35.6%respectively.On the contrary,that of low artemisinin content decreases from 12.0%to 2.2%for that originated from Xiushan,while for that from Youyang the percentage of single plants of high and second high artemisinin content increases from 14.0%and 25.0%to 22.9%and 28.6%respectively,and that of low artemisinin content plants decreases from 13.0%to 1.9%.In the 10 lines in 2007,the highest artemisinin content is 0.854%and the lowest is 0.782%,while the lines that the artemisinin,content is beyond and near 0.8%are 6 and 4 respectively.The cultivar with high and stable artemisinin content can be obtained by line pedigree breeding method.4 The artemisinin content of extracted parts decreases gradually from late vegetative stage to flowering stage.The yield of extracted parts reaches highest at full bud stage and lessen at stage of flower bud differentiation,and it even decreases at flowering stage,and the lowest is at late vegetative stage,thus,the artemisinin yield for each plant is the highest at full bud stage,then at the stage of flower bud,the third at flowering stage and the lowest at late vegetative stage.The artemisinin content of single plant at flower bud differentiation stage and full bud stage does not differ significantly.The content of artemisinin in the extracted parts of the same single plant at different stage is positively significant or obvious significant correlated,so the sample shall be taken at late vegetative stage to ensure enough time for artemisinin measurement before flowering.The artemisinin content in the extracted parts of different level branches of the same single plant at flower bud differentiation and full bud stage have no obvious difference,but the yield of artemisinin of each level benches differs significantly,because of yield difference of extracted parts,and the highest is the third level branch.Comprehensive consideration of the yield and artemisinin content of extracted parts in different level branches and that of each stage,when the leaves of the third level branches full spread at young bud stage,A,annua is harvested and the maximum economic benefit will he obtained.