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A columella (pl. columellae) is a sterile (non-reproductive) structure that extends into and supports the sporangium of some species. In fungi, the columella, which may be branched or unbranched, may be of fungal or host origin. Secotium species have a simple, unbranched columella, while in Gymnoglossum species, the
Zygote fungus sporangium, with columella labelled. Columella (in plants) is an axis of sterile tissue which passes through the center of the spore-case of mosses. [1] In fungi, it refers to a centrally vacuolated part of a hypha, bearing spores. The word finds analogous usage in myxomycetes. [citation needed]
An extension of the sporangiophore called the columella protrudes into the sporangium. The sporangium walls are easily ruptured to release the spores, which germinate readily to form a new mycelium on appropriate substrates. During sexual reproduction, compatible strains form short, specialized hyphae called gametangia. At the point where two ...
Stemonitis axifera requires about 20 hours to finish making its fruit bodies. Of this, eight hours are needed for induction of the sporangia and the development of the stalk and the columella, six hours more for the sporocarps to produce pigment and mature, and an additional six until the spores are discharged.
They reproduce by forming asexual and sexual spores. In asexual reproduction, sporangiospores are produced inside a spherical structure, the sporangium. Sporangia are supported by a large apophysate columella atop a long stalk, the sporangiophore. Sporangiophores arise among distinctive, root-like rhizoids.
While the fossil record of crown group hornworts only begins in the upper Cretaceous, the lower Devonian Horneophyton may represent a stem group to the clade, as it possesses a sporangium with central columella not attached at the roof. [22]
2. Of a columella, extending throughout the entire length, from the base of the gleba through to the peridium's apex. Found in gastromycetes such as Podaxis. Also called a stipe-columella or dendritic columella. [289] peridium The outer wall of a sporangium or other fruiting body. Can be either acellular or composed of plectenchyma. [290 ...
In the sporangia, there is an accumulation of nutrients, cytoplasm, and nuclei. An extension of the sporangiophore called the columella protrudes into the sporangium, and upon the maturation of the sporangiospores, burst of the sporangium allows for the dispersion of the spores, where wind is the primary dissemination method.