Studies On The Systematics Of Lycoris And Genetic Diversity Of Lycoris Longituba

Species included in the genus Lycoris Herb. are important ornamental and medical plants. There are about 20 species around the world. Our country is rich in wild resources of the genus, of which 15 species are native to China. In the first, the research development of Lycoris was summarized in the article, including the research of propagation and artificial cultivation, growth, breeding, chromosome, exploitation and economic value. The studies on the taxonomical systematics of Lycoris were also reviewed, and the problems in which were discussed. The problems in the taxonomical systematics are as follows: (1) the results of cytology are different from that of morphology, but results of karyotype analysis and that of RAPD are same. So it is seem too hard to divide Lycoris two subgenus according to corolla regularity; (2) the views on systematical tree of those species of Lycoris which have fairly more hybrid body are different; (3) the research of Lycoris on the systematical relationship of micro-morphology and anatomy is absent. Furthermore, the studies on the germplasmic resources of Lycoris longituba Y. Hsu et Q. J. Fan was not done, which has goodish economic value. Based on the researching of Lycoris leaf micro-morphology characters by SEM scanning, light microscope viewing and using paraffin method in the article, we try to provide the proofs of experiment to discuss the inter-species relationships on Lycoris. The useful microscope characters were as follows: the arrangement type of palisade tissue; the shape of adaxial epidermis cells; the stomata density; the stomata index; the wax ornamentation of outer stomata ledge. These characters were different among species of Lycoris. So these characters could be used as the characters indexes for differentiating species and studying systematic evolution of Lycoris. According to thirty-six morphological, anatomical, pollen morphological and cytological characters, the cladistic analysis of Lycoris was studied. Combining the results and the fingerprints of Lycoris on RAPD, the classification of Lycoris subgenus was discussed. It was suggestion that the position relation of the stamen and perianth slice could be used as the character for subgenus division. Using RAPD and ISSR, population genetic diversity and flower variation types of Lycoris longituba were also studied. The results were as follows: ①　Lycoris longituba had a high level of genetic diversity, but the differentiation among populations of which was low. And the great mass of genetic variance was found within populations, which indicated that Lycoris longituba had strong evolution potential. Therefore, under natural circumstance, Lycoris longituba would not to be in imminent danger. Thus, the breakage of the Lycoris longituba wild germplasm genetic resources mainly came from artificial interference. ②From UPGMA dendrogram using RAPD or ISSR method, three Lycoris longituba types were supported with molecular evidence, which were originally distinguished by flower color. Therefore, in the future use of Lycoris longituba germplasmic resources, different varieties of which could be cultivated.