%A Shen-Bin YANG, Sha-Sha XU, Xiao-Dong JIANG, Chun-Lin SHI, Ying-Ping WANG, Shuang-He SHEN %T Correcting the Response of Maximum Leaf Photosynthetic Rate to Temperatures in Crop Models %0 Journal Article %D 2018 %J Acta Agronomica Sinica %R 10.3724/SP.J.1006.2018.00750 %P 750-761 %V 44 %N 05 %U {https://zwxb.chinacrops.org/CN/abstract/article_6513.shtml} %8 2018-05-20 %X

Crop photosynthesis is sensitive to temperature variations, and the temperature dependence of photosynthesis is known to vary with growth environments and crop varieties. Crop models based on light use efficiency model, seldom correct parameter values related to the temperature dependence of photosynthesis for a specific crop, which unavoidably increases the simulation errors in dry biomass. In this paper, a scheme used to correct those parameter values was put forward with the rice crop model ORYZA2000 as an example to evaluate the scheme’s performance. The temperature-controlled experiments were conducted to observe photosynthesis at heading stage of rice variety Liangyoupeijiu in 2012 and 2013. The data were first analyzed to retrieve photosynthetic characteristics from light response curves and CO2 response curve. Based on their relationship with temperatures, temperature effect functions were established for all temperature sensitive photosynthetic parameters using Arrhenius and Peaked functions. A biochemical photosynthesis model was applied to simulate the changes of maximum leaf photosynthetic rate with temperatures, based on which temperature response curve for maximum leaf photosynthetic rate was produced and normalized to replace the default parameter values in ORYZA2000. The observations of above ground biomass (WAGT) of Liangyoupeijiu in two years were used to validate simulations before and after the correction. The normalized temperature response curve for maximum leaf photosynthetic rate of Liangyoupeijiu was different from the default response curve in ORYZA2000. From the corrected response curve, the optimal temperature for photosynthesis was between 38-40°C, higher than the default, and temperature effect coefficient was lower than the default between 10-20°C. Compared with the default parameter values, average relative error of the corrected parameter values was reduced by 3.3%. In conclusion, the method used in this paper can be an important reference for improving biomass simulation accuracy and analyzing temperature dependence of photosynthesis for different crop varieties.