Abstract: Taking sweet pepper cultivar Shujiao 13 as test material, a greenhouse experiment with different color (white, red, yellow, blue, green, and purple) plastic films was conducted in 2010 to study the effects of light quality on the cultivar’s dry matter formation and its partitioning. In all treatments, the correlation between the dry matter production per unit area (W_t) and the daily photosynthetic active radiation integral intercepted by plant canopy (PARi, MJ·m^-2) was accorded with exponential function W_t=22.07×e^0.0054λPARi. The plant total dry weight per unit area, fruit dry matter partitioning index (DMPI), fruit harvest index (HI), and fruit yield per unit area were the highest under red film but the lowest under purple film, the stem DMPI was the highest under blue film but the lowest under red film, the leaf DMPI was obviously higher under blue, green, and purple films than under red and yellow films, whereas the shoot DMPI had no significant difference among the treatments. It was considered that red and yellow films could promote the dry matter accumulation and fruit growth, while purple and blue films had obvious inhibitory effects. This study could provide a decision-making support for the light quality selection and environment optimization for the sweet pepper cultivation in greenhouse.

Key words: DNDC model, greenhouse gas emission, climate change.