The upper leaves are smaller and with lower photosynthetic rate.

上部叶片较小且光合速率较低。

youdao

Straw returned to field could increase nicotine content in upper leaves while decrease that in lower and middle leaves.

稻草还田提高产量、中上等烟、均价，从而提高产值和净效益。

youdao

Effects of different picking methods on chemical composition and content of volatile aromatic matter of upper leaves in flue-cured tobacco were studied.

研究了不同采收方式对烤烟上部烟叶化学成分和主要挥发性香气物质含量的影响。

youdao

Whitebeam trees marked the path to right and left, with their grey-green upper leaves and their sharp silver unders.

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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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Trees had lost their leaves and upper branches.

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