Abstract:

The LI-6400 Portable photosynthesis was used to study the photosynthetic characteristics in leaves of Carya cathyensis Sarg sapling. The results showed that the daily variation of net photosynthetic rate in leaves presented a bimodal curve, and there is an obvious “midday depression” phenomenon，the light saturation point was about 339 μmol/(m2?s), the light compensation point was about 23.2 μmol/(m2?s).Under the condition of optimum light intensity and temperature, elevation of CO2 concentration increased the Pn and the efficiency of high utilizing in Carya cathyensis Sarg sapling. The CO2 saturation point was about 1200 μl/L and CO2 compensation point was about 60~70 μl/L. The photosynthesis was more sensitive to the higher temperature (>25℃), belonging to neutral plant. The environmental conditions of the research areas could meet the basic needs of Carya cathyensis Sarg sapling growth.