Relationships among Net Photosynthetic Rate of Osmanthus fragrans,Physiological Factors and Environmental Factors

[Objective]The research aimed to study the relationships among net photosynthetic rate of Osmanthus fragrans,physiogical factors and environmental factors.[Method]Net photosynthetic rate of O.fragrans under natural condition was measured by using LICOR-6400XT portable photosynthesis system.Some physiological factors and environmental factors were measured at the same time,too.Then the relationships among net photosynthetic rate,physiological factors and environmental factors were analyzed.[Result]The results showed that photosynthetic active radiation was the dominant factor which affected net photosynthetic rate most.As photosynthetic active radiation was lower than 200 μmol/(m2·s),net photosynthetic was linear relative with photosynthetic active radiation.The equation was y=0.023 6x-0.437 7(R2=0.835 8).The trends of net photosynthetic rate and transpiration rate were more consistent,but there was no direct correlation between them.[Conclusion]Stomatal conductance and intercellular CO2 concentration were the main physiological factors that affected the net photosynthetic rate.They affected the net photosynthetic rate of O.fragrans directly.