Photosynthesis and Growth of Ardisia crenata and Ardisia punctata under Different Phosphorus Nutrition Levels

Ardisia crenata and Ardisia punctata are species of important medicinal and ornamental values.The effects of phosphorus nutrition on the gas exchange,pigment content,biomass allocation,nitrogen and phosphorus concentration of both A.crenata and A.punctata,were studied under four phosphorus nutrition levels.With the increased phosphorus supply,the net photosynthetic rate at saturated light (A),leaf area ratio (LAR),and the concentration of nitrogen and phosphorus increased in both species,and the biomass allocation of A.crenata to propagule also increased.So it was indicated that the increased phosphorus supply could facilitate the growth and reproduction of these two species.There was significant positive correlation between net photosynthetic rate and carboxylation efficiency as well as between carboxylation efficiency and phosphorus concentration in leaf,so it indicated that the enhanced photosynthetic capacity was probably correlated with the carboxylation efficiency.The positive effects of phosphorus faded when the phosphorus supply was more than 60 mg·kg^-1.The results could provide some useful information for the phosphorus supply in the culture of these two species.