抄録
Chemical constituents in root and evolutionarily neutral DNA base sequences were studied for L. duciformis, L. kongkaligensis, and L. nelumbifolia collected in Sichuan and Yunnan Provinces of China. The three species were indistinguishable genetically and morphologically. Twenty-eight samples were classified into four chemo-types (types 1-4). Sesquiterpenoids having eremophilane 1-3 and oplopane skeletons 4-7 were isolated from two (type 1) and three (type 2) samples, respectively. The structure of two new oplopane compounds 6 and 7 were determined spectroscopically. In 18 samples, phenylpropenoids 8-11 were the major component (type 3). In five samples, neither phenylpropenoids nor sesquiterpenoids were found (type 4). DNA analysis suggested that hybridization and introgression are extensive. All the present samples were not separated from one another or from L. franchetiana with the exception of sample 5. Since the sesquiterpenoid-producing samples (types 1 and 2) consist of minor group, the genetic analysis suggests that the ability of the production of eremophilane and oplopane sesquiterpenes was obtained by introgression. These samples were collected in the east or south edge of the distribution area. Thus the present results gave supports on the hypothesis that introgression occurs more frequently in the outer regions.
