对叶片的解剖学分析发现突变体中脉缺少细胞和近轴小维管束，导致披叶表型的产生。

Leaf anatomy results revealed the central vein lacks both clear cells and the adaxial small vascular bundle in dl2 mutant, which seemed to cause the drooping leaf phenotype.

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茎的初生维管束中有3大束和5～7小束，两个大维管束之间夹有2～3个小维管束，所有维管束在茎的横切面上呈环状排列；

There were 3 big vascular bundles and 5~7 small vascular bundles in young stem, and there were 2~3 small vascular bundles between two big vascular bundles, they were all arranged in circularity.

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维管束植物会产生一系列不同的小分子信号物质，就是所说的植物激素，它们调控着植物的生长分化进程。

Vascular plants produce an entire series of different small signalling molecules, so-called phytohormones, which regulate growth and differentiation processes.

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