In
mycology
Mycology is the branch of biology concerned with the study of fungi, including their genetic and biochemical properties, their taxonomy and their use to humans, including as a source for tinder, traditional medicine, food, and entheogens, as ...
, the term trama is used in two ways. In the broad sense, it is the inner, fleshy portion of a
mushroom
A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground, on soil, or on its food source. ''Toadstool'' generally denotes one poisonous to humans.
The standard for the name "mushroom" is t ...
's
basidiocarp
In fungi, a basidiocarp, basidiome, or basidioma () is the sporocarp of a basidiomycete, the multicellular structure on which the spore-producing hymenium is borne. Basidiocarps are characteristic of the hymenomycetes; rusts and smuts do ...
, or fruit body. It is distinct from the outer layer of tissue, known as the
pileipellis or
cuticle, and from the
spore
In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, f ...
-bearing tissue layer known as the hymenium. In essence, the trama is the tissue that is commonly referred to as the "flesh" of mushrooms and similar fungi.
[Largent D, Johnson D, Watling R. 1977. ''How to Identify Mushrooms to Genus III: Microscopic Features''. Arcata, CA: Mad River Press. . pp. 60–70.]
The second use is more specific, and refers to the "hymenophoral trama" that supports the
hymenium. It is similarly interior, connective tissue, but it is more specifically the central layer of hyphae running from the underside of the mushroom cap to the lamella or gill, upon which the hymenium rests. Various types have been classified by their structure, including trametoid, cantharelloid, boletoid, and agaricoid, with agaricoid the most common by far. In the agarcoid type, the central trama's hyphae usually run parallel to each other, with a clear boundary area called a sub-hymenium followed by the hymenium itself on the outer layer facing the environment.
The word "trama" is
Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
for the "
weft
Warp and weft are the two basic components used in weaving to turn thread or yarn into fabric. The lengthwise or longitudinal warp yarns are held stationary in tension on a frame or loom while the transverse weft (sometimes woof) is draw ...
" or "
woof" yarns in the weaving of cloth.
This is related to the basidiocarp trama being "filler" tissue and that analogously the woof yarn in weaving is sometimes called "fill". Furthermore, the trama tends to be soft tissue, and in weaving, the woof yarn is not tightly stretched; it therefore need not as a rule be as strong as the
warp
Warp, warped or warping may refer to:
Arts and entertainment Books and comics
* WaRP Graphics, an alternative comics publisher
* ''Warp'' (First Comics), comic book series published by First Comics based on the play ''Warp!''
* Warp (comics), a ...
yarn.
References
Mycology
Fungal morphology and anatomy
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