Effect of Water Stress on Maize Photosynthetic Characteristics

Based on the measurements of maize leaf photosynthesis, the light response curves of Nongda108 and Jingke25 photosynthesis were fitted with rectangle hyperbolae. The result showed that the values of intrinsic quantum efficiency for CO2 uptake(α), light-saturated net photosynthetic rate(Pn), and dark respiration rat(Rd), light compensation point(LCP) and light saturation point(LSP) were decreased on water stress. Nongda108 decreased slowly and Jingke25 decreased rapid. The decrease of net photosynthetic rate were result from stomatal limit factor and nonstomatal limit factor under water stress. Jingke25 with low light use efficiency and water use efficiency under water stress. The affect factor is stomatal limit. Nongda108 still with high light use efficiency and water use efficiency under water stress. The affect factor is nonstomatal limit.