包括根或茎的维管组织及相关薄壁组织，若有维管束鞘和内皮包被则这二者也属于中柱结构。

Stele the vascular tissue and associated parenchyma tissue and (if present) the surrounding pericycle and endodermis of a stem or root.

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茎中维管组织的排列方式多种多样，由此产生多种类型的中柱。

The arrangement of vascular tissue ( the vascular system ) in the stem is very varied , giving a number of different types of stele.

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