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Related to protostele: eustele, siphonostele


 (prō′tə-stēl′, prō′tə-stē′lē)
n. Botany
A stele that forms a solid core of xylem encased by phloem.

pro′to·ste′lic (-stē′lĭk) adj.


(ˈprəʊtəˌstiːl; -ˌstiːlɪ)
(Botany) a simple type of stele with a central core of xylem surrounded by a cylinder of phloem: occurs in most roots and the stems of ferns, etc
ˌprotoˈstelic adj


(ˈproʊ təˌstil, -ˌsti li)

the solid stele of most plant roots, having a central core of xylem enclosed by phloem.
pro`to•ste′lic, adj.
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References in periodicals archive ?
The anatomy was simple, the central strand of sclerenchyma of the algal progenitors becoming a strand of tracheids forming the earliest type of stele, the protostele. The predecessors of sieve tubes were elongated parenchymatous cells which differentiated around the central strand.
It is doubtful whether the terminology used to describe the Matteuccia apex would be as appropriate in analyzing structurally similar shoot apices of ferns with protosteles or ferns with highly dissected or polycyclic steles.