Photoresponse Characteristics of Carallia brachiata Seedlings and Selection of Optimal Curve Models

In order to reveal the photosynthetic physiological characteristics of Carallia brachiata, C.brachiata seedlings were selected as the research object. The photosynthetic-light response curves was measured by Li-6400, and photosynthetic-optical response models suitable for C.brachiata seedlings were screened from the commonly used 6 photosynthetic curve fitting models. The results showed that the photosynthetic-optical response curve fitted by the right-angle hyperbola correction model was the best, and had a photo-inhibition phenomenon in accordance with the plant growth law. The P_max, I_sat, I_c, R_d were the closest to the measured values in the modified rectangular hyperbola model. The correlation coefficient R² was 0.998, which was the largest among the 6 models. The MAE and MSE were the smallest and the model had higher fitting accuracy. Therefore, the hyperbola correction model was the best fitting model for the photosynthesis-photoresponse curve of C.brachiata.