Abstract:In order to understand the photosynthetic characteristics of Podocarpus nagi, the photosynthetic pigment content and gas exchange parameters of green and striped leaves of 3-year-old P. nagi seedlings were measured. The results showed that the chlorophyll (Chl) a, Chl b, carotenoid (Car), Chl a+b, Chl a/b and Chl a+b/Car in green leaves were significantly higher than those in striped leaves. The initial quantum efficiency, maximum photosynthetic rate and dark respiration rate in green leaves were significantly higher than those in striped leaves, and the light saturation point and light compensation point were significantly lower than those in striped leaves (P<0.05). The initial carboxylation efficiency, photosynthetic capacity, CO2 saturation point and photorespiration rate of green leaves were higher than those of striped leaf, and CO2 compensation point of green leaves was lower than that of striped leaves. The stomatal conductance, transpiration rate and water use efficiency increased with the increment of photosynthetic active radiation with the order of green leaf>striped leaf, while the intercellular CO2 concentration had opposite trend with striped leaf>green leaf. So, it could be rationally planted according to the photosynthetic characteristics of two different color leaves according to the different phytosynthetic characteristics of two color leaves of P. nagi, which green leaf had strong ability to use weak light and striped leaf had strong ability to use stronger light.
