The Photosynthetic Characteristics of Camellia euphlebia

The photosynthetic characteristics of leaves in Camellia euphlebia were studied with LI-6400 (Li-Cor Inc., USA) portable photosynthesis system. The results showed that the diurnal changes of photosynthetic rate (Pn) in C. euphlebia exhibited a mono-peak style, and the maximum value of Pn appeared at 11:00 am in summer. The maximum photosynthetic rate(Pmax), light saturation point(LSP), light compensation point(LCP)for the leaves of C. euphlebia were 3.81 μmol·m-2·s-1, 459.9 μmol·m-2·s-1 and 6.9 μmol·m-2·s-1, respectively. The light saturation and compensation point were very low, which indicated that C. euphlebia was a shade plant. Under the condition of optimum light intensity and temperature, the net photosynthetic rate of Camellia euphlebia increased linearly when the concentration of CO2 enhanced from 50 μmol·mol-1 to 800 μmol·mol-1. Elevation of CO2 concentration increased the Pn and the efficiency of ligh utilizing in Camellia euphlebia. The CO2 saturation (CSP), compensation point(Г), the maximum carboxylation rate (Vcmax)and maximum rate of electron transport(Jmax) were about 1 200 μmol·mol-1, 70.1 μmol·mol-1 , 17.5 μmol·m-2 ·s-1, respectively.