Chin J Plant Ecol ›› 2012, Vol. 36 ›› Issue (12): 1277-1285.DOI: 10.3724/SP.J.1258.2012.01277

• Research Articles • Previous Articles     Next Articles

Comparison between modified exponential model and common models of light-response curve

CHEN Wei-Ying1,2,*(), CHEN Zhen-Yong1, LUO Fu-Yan1, PENG Zheng-Song1, YU Mao-Qun2   

  1. 1. Key Laboratory of Southwest China Wildlife Resources Conservation, College of Life Science, China West Normal University, Nanchong, Sichuan 637009, China
    2. Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
  • Received:2012-09-11 Accepted:2012-11-01 Online:2012-09-11 Published:2012-11-28
  • Contact: CHEN Wei-Ying


Aims Our primary aim was to compare the differences and accuracies of light-response curves between C3 and C4 plants as described by five light-response curve models: modified exponential (a new model), rectangular hyperbola, modified rectangular hyperbola , non-rectangular hyperbola and exponential. Methods Light-response curves of Xizang hulless barley (Hordeum vulgare), grain sorghum (Sorghum bicolor), amaranth (Amarantus mangestbus) and Pinellia ternate were measured by a portable photosynthetic gas analysis system with a LED radiation source (LI-6400). The collected data were used to fit and test the five light-response curve models, and photosynthetic parameters, such as light saturation point and maximum net photosynthetic rate, were compared with the measured values. Important findings The results show that the light-response curves of the four plants described by the modified exponential and modified rectangular hyperbola models are better than the rectangular hyperbola, non-rectangular hyperbola and exponential models, especially when light intensity is beyond the light saturation point. The results also indicate that the modified exponential and modified rectangular hyperbola models also describe the light-response curves characteristics of C4 plants, although the two models were established based on C3 plants. Therefore, these two models provide a reference for the application of light-response curve models in plants with different photosynthetic pathways including C3 and C4.

Key words: light response curves, light saturation point, maximum net photosynthetic rate, modified exponential model