Abstract: Under full exposure and 20% exposure to light, the field-cultivated Catharanthus roseus(L.) Don. was used to investigate the changes of biomass distribution, antioxidative secondary metabolites and contents of objective active products such as vindolin, catharanthine and vinblastine after a growing season. The results indicated that the total biomass of C.roseus was extremely restrained by the low light intensity, especially the investment of generative propagation; the contents of total phenolics and total flavonoids in leaves under low light intensity decreased distinctly, and the contents of dry weight were 62.50% and 50.00% of the control, respectively, while the content of proanthocyanidins increased slightly, but not remarkably as compared to the full exposure group; vindolin and catharanthine contents under low light intensity were much higher than that of control while vinblastine content increased slightly; the contents of three alkaloids all reduced, which was affected by the reduction of biomass. In conclusion, C.roseus could regulate physiological metabolism to adapt the low light environment, including the remarkable increased content of vindolin and catharanthine. Land resource was fully utilized by planting C.roseus in low light environment. Meanwhile, the needs of vindolin and row material of vinblastine were satisfied as well.

Key words: Catharanthus roseus(L.) Don., low light stress, biomass distribution, objective active products, spatial planting