Abstract:Camptotheca acuminata Decaisne (Nyssaceae) is a native Chinese tree that produces camptothecin (CPT), a pentacyclic quinoline alkaloid, which is known for its remarkable inhibitory activity against tumour cells. To investigate the effects of shading on the biomass, chlorophyll content, photosynthesis and CPT content on leaves of C. acuminata, the seedlings of C. acuminata with 4 pairs of leaves were shaded by yellow, red, and blue film in plots in a greenhouse. The resulting relative light intensity were 60...