A Preliminary Study Of The Dwarf Lilyturf Root Development

In this paper, the structure of the root tubers of Ophiopogon(Ophiopogon japonicus (L.f.) Ker-Gawl.) and Liriope spicata (Liriope spicata (Thunb.) Lour.) at different developmental stages was observed under light microscope by anatomical methods. The results indicated that root tubers enlargement was initiated from the apical part of adventitious root and that both the cell layer number and cell size in cortex changed dramatically during development in both species, which finally enlarged the root tubers. But we found that the cell layer number increasing in Liriope spicata contributed more than cell size change to the root tuber enlargement, while in O.japonicus both cell layer number and cell size contribute equally to the root tuber development.By ELISA to determine the content of four endogenous hormones in the underground parts of O.japonicus during the development process. During four periods the content of four kinds endogenous hormones measured in the tuberous roots were lower than in the adventitious roots, and trends were different. In the tuber, the contents of GA and ZR increased gradually, and ZR increased lowlier. The content of IAA changed little, and ABA showed a decreasing trend. In adventitious roots the GA content increased firstly and then decreased. The IAA content are stability, the content of ZR and ABA firstly increased and then decreased, and then increased to the maximum. As tuber developing GA/ABA ratio gradually increased, and ABA/ZR decreased gradually with the development of the root tubers.We established a method to determine Sucrose and glucose by HPLC-ELSD in the process of O.japonicus tuber development, the contents of sucrose and glucose firstly increased and then decreased, and in the adventitious roots the contents of sucrose and glucose showed the same changing trend, but in the same period the contents were lower than in the tuber content. Sucrose and glucose contents in the nutrition root changed very slowly.There were31kinds of of compounds be found in the metabolic compounds in the underground parts which is the determination of O.japonicus.31kinds of compounds was detected in tubers which is the most in the three part of O.japonicus, in additon, we detected28kinds and24kinds in nutritive roots and in adventitious roots respectively. Principal component analysis showed that the substances contained during the last three period is different from the other parts of the period the tuber development, which suggested that the metabolic processes may be different.According the Transcription sequence of O.japonicus, we have got106113unigene with the mean unigene size was332bp,28335Unigenes have GO functional classifica-tion,35305unigene assigned to121KEGG pathway and34746genes have a COG classification. In the expression profiles of O.japonicus, we have got10146Differentially Expressed Genes(DEG) between tuberous roots and adventitious roots,3527DEG between tuberous roots and nutritive roots,4770DEG between nutritive roots and adventitious roots. We have got980target DEG at last. From the angle of morphological development to analysis the date, we have got some genes which have possibility to influence the enlargement of O.japonicus tubers, including actions, pectinesterase and microtublin. These genes provide a basis for further studying of the mechanism of tuber development.