| 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 annua 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. The artemisinin content differs greatly among single plants due to the heredity differences, so both yield and content of artemisinin are low. Understanding the biological characteristics of A. annua is very important for the success of introduction 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, extraction methods and conditions of artemisinin in laboratory analysis are first studied as the basis for selection of extraction methods when artemisinin content of A. annua is measured in breeding proces. 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 % Soaking extraction under room temperature and constant temperature are simple and can extract many samples each time, but it is time consuming. These methods fit to large scale A. annua single plant selection. As for soaking extraction under room temperature, the extraction time varies with the change of environment temperature; for soaking extraction under constant temperature, the extraction time can be easily determined and artemisinin can be thoroughly extracted in five days at 40 with petroleum ether as the extracting liquid renewed each day. Stiring extraction and Soxhlet's extraction require less time but the numbers of samples extracted at the same time are limited. The latter two methods can be used for quick measurement when the numbers of samples are small. The optimal parameter for stiring extraction is extracting 3h at 45 with the stiring rate of 600r-min-1; for the Soxhlet's extraction, it is: extracting 4h at 70 . If the temperature is too high and extraction time is long, the artemisinin will be decomposed and its extracted amount will be decreased.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 canendure cold and smoothly pass the winter. The vigorous vegetative period of A. annua isbetween early June and late July, then flower bud differentiates in late July to middle August, and blossom is in late September to late October. The growth duration is different among A. annua comning from different origin. The A. annua from Changsha district has die shortest growth duration and that from Jishou district longest and that from Shuangfeng district sets between them. The yield and artemisinin content of A. annua introduced from Jishou 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 Changsha, Shuangfeng and Jishou 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...
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