Study on Light-response Curve of Photosynthesis of Different Oat Varieties at Early Grain Filling Stage

In order to study the photosynthetic capacity of different oat varieties,the light-response curve of photosynthesis of four oat varieties were investigated at early grain filling stage.The results showed that Bayou 1 was the best on photosynthetic capacity.When light intensity increased,net photosynthetic rate,stomatal conductance and transpiration rate of all varieties increased,and cell interval concentration of CO2 decreased.The photosynthetic indicators existed significant differences between them,and the response to light intensity of Bayou 1 is more sensitive.With the increase of light intensity,net photosynthetic rate,stomatal conductance and transpiration rate increased rapidly.In different light intensities,photosynthetic rate of bayou1 was the highest.Its maximum rate was 32.3 μmol CO2·m-2·s-1 when the light intensity reached 2 000 μmol·m-2·s-1.