The secondary structure of rhizome include epiderm, cortex and vascular tissue, pith ray is developed.

根状茎的次生结构由外向内为表皮，皮层和维管柱，髓射线发达。

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Having the epidermis, cortex, starch sheath, perivascular sclerenchyma, six vascular bundles, pith and pith ray, the stem is similar to the root in their structure.

该植物茎与根茎的构造相似，均有表皮、皮层、淀粉鞘、周维纤维、六束维管束、髓及髓射线。

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Latent root primordium was not found in shoots in test tubes. The induced root primordium which originated from the division and differentiation of pith ray cell developed into the adventitious roots.

并对四倍体刺槐无性系试管苗不定根的发育过程进行了解剖观察，结果表明试管苗嫩梢无潜伏根原基，不定根由诱生根原基发育形成，诱生根原基源于髓射线细胞的分裂和分化。

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