Stomatal and inter conductance constrain analysis for photosynthesis of C3 and C4 crops.

To demonstrate the difference between stomatal conductivity and inter conductance of C3 and C4 crops,this paper compared the two conductivities by using soybean and corn.The results showed that the stomatal conductance in soybean was higher than corn,but inverse results were found for inter conductance.The difference indicated that leaf photosynthesis of corn was mainly constrained by stomatal conductance and leaf photosynthesis of soybean was mainly constrained by carboxylic ability.CO2 deficit could occur to corn at low CO2 concentration level,and the limitation from carboxylic ability constrained the increase of photosynthesis even under high CO2 concentration level.