Leaf photosynthetic light response of summer maize: comparison of models and analysis of parameters

Abstract

An experiment was performed in order to study the applicability of light-response models for summer maize (Zea mays L.) by using rectangular hyperbola model, nonrectangular hyperbola model, exponential model, binomial regression model, and modified rectangular hyperbola model (Ye model), respectively. Our results showed that the fitted effect of Ye model was best and photosynthetic parameters were closest to the observation. The photoinhibition coefficient was significantly negatively correlated with the light-saturation point (Is), the light-saturation coefficient (γ), and maximum net photosynthetic rate at light-saturation point (PNmax), respectively. PNmax and Is, apparent quantum yield, and γ performed significantly positive relationship, respectively. When the soil volumetric water content varied from 13 to 21%, PNmax had significant positive correlation with the soil water content and stomatal conductance. Under water and temperature stress, the net photosynthetic rate decreased and photoinhibition occurred, which could be well simulated by the Ye model. It seems that Ye model would have more applications, especially for the regions with strong solar radiation.