The upper leaves are smaller and with lower photosynthetic rate.

上部叶片较小且光合速率较低。

youdao

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 the upper leaves.

下位叶比上位叶对土壤氮的供应状况更为敏感，随着施氮量的增加，水稻叶片氮素含量、叶绿素含量、SPAD值相应的增加，而下位叶的增幅更明显。

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The upper leaves 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.

以烤烟品种NC89、K326、RG11的上部叶为材料，对变黄期至定色期烟叶厚度及解剖结构的变化进行了切片观察。

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The rare leaf is a part of the tobacco plant called the medio tiempo, taken from the upper leaves of the plant, but which not every plant produces, making it rare.

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