Theupperleaves are smaller and with lower photosynthetic rate.
上部叶片较小且光合速率较低。
2
Leaf N/ chlorophyll content and SPAD value increased with the increasing N fertilizer, and the lower leaves were more sensitive to the soil N supply than theupperleaves.
Theupperleaves of flue_cured tobacco CV. NC89, K326, RG11 were sliced, and their changes of thickness and dissecting structure were observed from the stages of yellowing to color fixing.