P van Rijckevorsel wrote:

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According to Harris & Harris it [spicule] is also used for a small spike in plants, an
outgrowth of the epidermis
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According to the APS Glossary of Plant-Pathological Terms, spicules are
paired, sclerotized structures that are the male copulatory organs of
Nematodes; or fungal needlelike outgrowths. Rust spores are, for
instance, decorated with spicules, which are believed to help spores to
be attached to host plant surface.

Regards.

--
Ivan Sache