Hyphae Sentence Examples
The internal tissue of the body of the solid higher Fungi, particularly the elongated stalks (stipes) of the fructifications of the Agarics, consists of hyphae running in a longitudinal direction, which no doubt serve for the conduction of organic food substances, just as do the trumpet-hyphae, similar in appearance, though not in origin, of the higher Brown Seaweeds.
The hyphae of the mycelium of this fungus are septate, with numerous short branches.
The food so absorbed passes to the outer cortical mycellum, and from this tc the inner hyphae, which appear to be the organs of the interchangi of substance, for they are attracted to the neighborhood of thi nuclei of the cells, which they enter, and iii which they form agglom erations of interwoven filaments.
The inability to enter the cells may be due to the lack of chemotactic bodies, to incapacity to form cellulose-dissolving enzymes, to the existence in the hostcells of antagonistic bodies which neutralize or destroy the acids, enzymes or poisons formed by the hyphae, or even to the formation and excretion of bodies which poison the Fungus.
The mildew is in its turn attacked by a fungus of the same tribe, Cicinnobolus Cesatii, which lives parasitically within the hyphae of its host, and at times even succeeds in destroying it.Advertisement
The segments of the hyphae in this group usually contain several nuclei.
A solid fungal body may usually be seen to consist of separate hyphae, but in some cases these are so bent and closely interwoven that an appearance like that of ordinary parenchymatous tissue is obtained in section, the structure being called pseudo parenchyrna.
On the under side of the leaf these patches are white and are composed of the spore-bearing hyphae.
The green (or blue-green) cells were termed gonidia by Wallroth, who looked upon them as asexual reproductive cells, but when it was later realized that they were not reproductive elements they were considered as mere outgrowths of the hyphae of the thallus which had developed chlorophyll.
The majority of the lichens, however, possess a stratified thallus in which the gonidia are found as a definite layer or layers embedded in a pseudoparenchymatous mass of fungal hyphae, i.e.Advertisement
By the fusion of the hyphae in the middle of the mycelium a pseudo-parenchymatous cortical layer has begun to form.
The exact relation of gonidia and hyphae has been investigated e specially by Bornet and also by Hedlund, and very considerable differences have been shown to exist in different genera.
In many other cases, especially those algae possessing Pleurococcus as their gonidia, there are no penetrating hyphae, but merely From Strasburger's Lehrbuck der Botanik, by permission of Gustav Fischer.
The soredia are found in a large number of lichens, and consist of a single gonidium or groups of gonidia, surrounded by a sheath and hyphae.
These were investigated by Tulasne in 1853, who gave them the name spermogonia The lower, ventral portion of the sperm09' gonium is lined by delicate hyphae, the sterigmata, which give origin to minute colourless cells, the spermatia.Advertisement
In other lichens we should expect to find the ascogenous hyphae arising directly from the vegetative hyphae as in Humaria rutilans among the ordinary fungi, where the process is associated with the fusion of vegetative nuclei.
Clavaria mucida, however, h a s apparently some claims to be considered as a Basidiolichen, since the base of the fruit body and the thallus from which it arises, according to Coker, always shows a mixture of hyphae and algae.
The algal cells are usually controlled in their growth by the hyphae and are prevented from forming zoospores, and in some cases, as already described, the algal cells are killed sooner or later by the fungus.
The wall of the hyphae of the fungus give in the young state the ordinary reactions of cellulose but older material shows somewhat different reactions, similar to those of the so-called fungus-cellulose.
The spores, which may be unior multi-cellular, are either abstricted free from the ends of hyphae (acrogenous), or formed from segments in their course (chlamydospores) or from protoplasm in their interior (endogenous).Advertisement
They extend back beyond the Carboniferous, where they occur as hyphae, &c., preserved in the fossil woods, but the best specimens are probably those in amber and in siliceous petrifactions of more recent origin.
Individual hyphae or their branches often exhibit specializations of form.
Many parasitic hyphae put out minute lateral branches, which pierce the cell-wall of the host and form a peg-like (Trichosphaeria), sessile (Cystopus), or stalked (Hemileia), knot-like, or_a B FIG.
In Rhizopus certain hyphae creep horizontally on the surface of the substratum, and then anchor their tips to it by means of a tuft of short branches (appressorium), the walls of which soften and gum themselves to it, then another branch shoots out from the tuft and repeats the process, like a strawberry-runner.
Many fungi (Phallus, Agaricus, Fumago, &c.) when strongly growing put out ribbon-like or cylindrical cords, or sheet-like mycelial plates of numerous parallel hyphae, all growing together equally, and fusing by anastomoses, and in this way extend long distances in the soil, or over the surfaces of leaves, branches, &c. These mycelial strands may be white and tender, or the outer hyphae may be hard and black, and very often the resemblance of the subterranean forms to a root is so marked that they are termed rhizomorphs.Advertisement
The outermost hyphae may even put forth thinner hyphae, radiating into the soil like root-hairs, and the convergent tips may be closely appressed and so divided by septa as to resemble the root-apex of a higher plant (Armillaria mellea).
These reserve stores may be packed away in single hyphae or in swollen cells, but the hyphae containing them are often gathered into thick cords or mycelial strands (Phallus, mushroom, &c.), or flattened and anastomosing ribbons and plates, often containing several kinds of hyphae (Merulius lacrymans).
In other cases the strands undergo differentiation into an outer layer with blackened, hardened cell-walls and a core of ordinary hyphae, and are then termed rhizomorphs (Armillaria mellea), capable not only of extending the fungus in the soil, like roots, but also of lying dormant, protected by the outer casing.
Such aggregations of hyphae frequently become knotted up into dense masses of interwoven and closely packed hyphae, varying in size from that of a pin's head or a pea (Peziza, Coprinus) to that of a man's fist or head, and weighing io to 25 lb or more (Polyporus Mylittae, P. tumulosus, Lentinus Woermanni, P. Sapurema, &c.).
The interwoven hyphae fuse and branch copiously, filling up all interstices.
In many cases the swollen cell-walls serve as reserves, and sometimes the substance is so thickly deposited in strata as to obliterate the lumen, and the hyphae become nodular (Polyporus sacer, P. rhinoceros, Lentinus Woermanni).
The simpler mycelia consist of hyphae all alike and thin-walled, or merely differing in the diameter of the branches of various orders, or in their relations to the environment, some plunging into the substratum like roots, others remaining on its surface, and others (aerial hyphae) rising into the air.
Such hyphae may be multicellular, or they may consist of simple tubes with numerous nuclei and no septa (Phycomycetes), and are then non-cellular.
In the more complex tissue-bodies of higher fungi, however, we find considerable differences in the various layers or strands of hyphae.
An epidermis-like or cortical protective outer layer is very common, and is usually characterized by the close septation of the densely interwoven hyphae and the thickening and dark colour of their outer walls (sclerotia, Xylaria, &c.).
Fibre-like hyphae with the lumen almost obliterated by the thick walls occur in mycelial cords (Merulius).
In Merulius lacrymans Hartig has observed thin-walled hyphae with large lumina, the septa of which are perforated like those of sieve-tubes.
The oidia of Erysipheae contain fibrosin bodies and the hyphae of Saprolegnieae cellulin bodies, but starch apparently never occurs.
That such enzymes are formed in the protoplasm is evident from the behaviour of hyphae, which have been observed to pierce cell-membranes, the chitinous coats of insects, artificial collodion films and layers of wax, &c. That a fungus can secrete more than one enzyme, according to the materials its hyphae have to attack, has been shown by the extraction of diastase, inulase, trehalase, invertase, maltase, raffinase, malizitase, emulsin, trypsin and lipase from Aspergillus by Bourquelot, and similar events occur in other fungi.
Although many fungi have been regarded as devoid of nuclei, and all have not as yet been proved to contain them, the numerous investigations of recent years have revealed them in the cells of all forms thoroughly examined, and we are justified in concluding that the nucleus is as essential to the cell of a fungus as to that of other organisms. The hyphae of many contain numerous, even hundreds of nuclei (Phycomycetes); those of others have several (Aspergillus) in each segment, or only two (Exoascus) or one (Erysiphe) in each cell.
Morphologically considered, spores are marked by peculiarities of form, size, colour, place of origin, definiteness in number, mode of preparation, and so forth, such that they can be distinguished more or less sharply from the hyphae which produce them.
The term "receptacle" sometimes applied to these spore-bearing _ hyphae is better replaced by sporophore.
The sporophore is obsolete when the spore-bearing hyphae are not sharply distinct from the mycelium, simple when the constituent hyphae are isolated, and compound when the latter are conjoined.
The chief distinctive characters of the sporogenous hyphae are their orientation, usually vertical; their limited apical growth; their peculiar branching, form, colour, contents, consistency; and their spore-production.
Compound sporophores arise when any of the branched or unbranched types of spore-bearing hyphae described above ascend into the air in consort, and are more or less crowded into definite layers, cushions, columns or other complex masses.
The same laws apply to the individual hyphae and their branches as to simple sporophores, and as long as the conidia, sporangia, gametes, &c., are borne on their external surfaces, it is quite consistent to speak of these as compound sporophores, &c., in the sense described, however complex they may become.
Among the simplest cases are the sheet-like aggregates of sporogenous hyphae in Puccinia, Uromyces, &c., or of basidia in Exobasidium, Corticium, &c., or of asci in Exoascus, Ascocorticium, &c. In the former, where the layer is small, it is often termed a sorus, but where, as in the latter, the sporogenous layer is extensive, and spread out more or less sheet-like on the supporting tissues, it is more frequently termed a hymenium.
Another simple case is that of the columnar aggregates of sporogenous hyphae in forms like Stilbum, Coremium, &c. These lead FIG.
Solenia, Cyphella - and even simpler cases are met with in Mortierella, where the zygospore is invested by the overgrowth of a dense mat of closely branching hyphae, and in Gymnoascus, where a loose mat of similarly barren hyphae covers in the tufts of asci as they develop.
In other cases (Diplodia, Aecidium, &c.) conidial or oidial "fructifications" arise by a number of hyphae interweaving themselves into a knot, as if they were forming a sclerotium.
Much more complicated are the processes in a large series of "fructifications," where the mycelium first develops a densely packed mass of hyphae, all alike, in which labyrinths of cavities subsequently form by separation of hyphae in the previously homogeneous mass, and the hymenium covers the walls of these cavities and passages as with a lining layer.
Pythium is a semiaquatic form attacking seedlings which are too plentifully supplied with water; its hyphae penetrate the cell-walls and rapidly destroy the watery tissues of the living plant; then the fungus lives in the dead remains.
When the free ends of the hyphae emerge again into the air they swell up into spherical bodies which may either fall off and behave as conidia, each putting out a germ-tube and infecting the host; or the germ-tube itself swells up into a zoosporangium which develops a number of zoospores.
Plasmopara, &c. In Cystopus (Albugo) the "conidia" are abstricted in basipetal chain-like series from the ends of hyphae which come to the surface in tufts and break through the epidermis as white pustules.
Those parts nearest the fly and best supplied develop barren hyphae only; in a zone at the periphery, where the products of putrefaction dissolved in the water form a dilute but easily accessible supply, the zoosporangia are developed in abundance; oogonia, however, are only formed in the depths of this radiating mycelium, where the supplies of available food materials are least abundant.
They are often devoid of hyphae, or put forth fine protoplasmic filaments into the cells of their hosts.
Most genera are saprophytes, but some - Chaetocladium, Piptocephalis - are parasites on other Mucorini, and one or two are associated casually with the rotting of tomatoes and other fruits, bulbs, &c., the fleshy parts of which are rapidly destroyed if once the hyphae gain entrance.
The ascocarps can be distinguished into two portions, a mass of sterile or vegetative hyphae forming the main mass of the fruit bod y, and surrounding the fertile ascogenous hyphae which bear at their ends the asci.
When the ascogonium (female organ) is present the ascogenous hyphae arise from it, with or without its previous fusion with an antheridium.
The asci may be derived from the terminal cell of the branches of the ascogenous hyphae, but usually they are derived from the penultimate cell, the tip curving over to form the so-called crozier.
Concerning the second question, the recent investigations of Buchner ascogenous hyphae with their asci represent the sporophyte since they are derived from the fertilized ascogonium.
They form a superficial mycelium on the surface of the plant, the hyphae not usually penetrating the tissues but merely sending haustoria into the epidermal cells.
The conidia are fragrant and are carried by bees to the stigma of the bilberry; here they germinate with the pollen and the hyphae pass with the pollen tubes down the style; the former infect the ovules and produce sclerotia, therein reducing the fruits to a mummified condition.
The cytological details of development of the perithecia are not well known; most of them appear to develop their ascogenous hyphae in an apogamous way without any connexion with an ascogonium.
Owing to the presence of oily globules of an orange-yellow or rusty-red colour in their hyphae and spores they are termed Rust-Fungi.
The gleba is usually differentiated into a number of chambers which are lined directly by the hymenium (basidial layer), or else the chambers contain an interwoven mass of hyphae, the branches of which bear the basidia.
Pfeffer showed that certain substances in definite concentrations cause the tips of hyphae to turn towards them; other substances, though not innutritious, repel them, as also do nutritious bodies if too highly concentrated.
Marshall Ward showed that the hyphae of Botrytis pierce the cell-walls of a lily by secreting a cytase and dissolving a hole through the membrane.
Miyoshi then demonstrated that if Botrytis is sown in a lamella of gelatine, and this lamella is superposed on another similar one to which a chemotropic substance is added, the tips of the hyphae at once turn from the former and enter the latter.
If a thin cellulose membrane is interposed between the lamellae, the hyphae nevertheless turn chemotropically from the one lamella to the other and pierce the cellulose membrane in the process.
The hyphae will also dissolve their way through a lamella of collodion, paraffin, parchment paper, elder-pith, or even cork or the wing of a fly, to do which it must excrete very different enzymes.
If the membrane is of some impermeable substance, like gold leaf, the hyphae cannot dissolve its way through, but the tip finds the most minute pore and traverses the barrier by means of it, as it does a stoma on a leaf, We may hence conclude that a parasitic hyphae pierces some plants or their stomata and refuses to enter others, because in the former case there are chemotropically attractive substances present which are absent from the latter, or are there replaced by repellent poisonous or protective substances such as enzymes or antitoxins.
The developing seed thus encloses fungal hyphae, which remain dormant within the seed and in spring develop symbiotically with the growth of the wheat plant, doing no apparent injury until the time of fruiting is reached, when the fungus takes complete possession and fills the new seed with a mass of darkcoloured spores.
Radially placed gaps in the tissue (at first erroneously interpreted as medullary rays, but subsequently more aptly compared to the air-spaces of large Algae) contain very sparse hyphae, which here branch more freely than elsewhere.
Transverse septa have occasionally, but rarely, been detected in the smaller hyphae.
Later writers, influenced by the occasional occurrence of transverse walls in the smaller hyphae, have laid more stress on Laminariaceous affinities.
In examining the tissues of fossil plants of that epoch nothing is more common than to meet with mycelial hyphae in and among the cells; in many cases the hyphae are septate, showing that the higher Fungi (Mycomycetes), as distinguished from the more algoid Phycomycetes, already existed.
Such particles can include small pieces of silica, pollen grains, fungal hyphae and other organic detritus 1.
The main body of most fungi is made up of fine, branching, usually colorless threads called hyphae.
Note the intact immature nodules and the ruptured lesions showing white hyphae.
Spores carried in the air land on dead or dying trees and produce hyphae which ramify through the wood.
Molds are composed of numerous, microscopic, branching hyphae known collectively as a mycelium.
The antibody recognizes a water soluble thermostable antigen that is present in the extracellular matrix surrounding the hyphae.
It takes only a few days for mold spores to germinate, and only a few weeks to extend hyphae and grow extensively.
At the onset of sporulation large amounts of aerial hyphae are produced.
It has a mycelium of narrow, branched and septate hyphae.
The directional growth of germ tubes in relation to stomata and veins, and of intercellular hyphae in relation to veins, were recorded.
However, it is not present in secondary necrotrophic hyphae, which suggests that it is specific to biotrophic infection structures.
This allows a narrow penetration peg to enter the leaf epidermis and colonize the tissue, later forming large bulbous infection hyphae.
Each fungus will have vast numbers of these hyphae, all intertwining to make up a tangled web called the mycelium.
Grows to form a fungus-like, branching mycelium with aerial hyphae bearing conidia.
Ephebe pubescens) the form of thallus is the form of the filamentous alga which is merely surrounded by the fungal hyphae (fig.
In some of the simpler fungi the spores are not borne on or in hyphae which can be distinguished from the vege A tative parts or mycelium, but in the vast majority of cases the sporogenous hyphae either ascend free into the air or radiate into the surrounding water as distinct branches, or are grouped into special columns, cushions, layers or complex masses obviously different in colour, consistency, shape and other characters from the parts which gather up and assimilate the food-materials.
When the flowers form, however, the mycelium sends hyphae into the young ovaries and rapidly replaces the stores of sugar and starch, &c., which would have gone to make the grain, by the soot-like mass of spores so well known as smut, &c. These spores adhere to the grain, and unless destroyed, by "steeping" or other treatment, are sown with it, and again produce sporidia and yeast-conidia which infect the seedlings.
The remarkable case of life in common first observed in lichens, where a fungus and an alga unite to form a compound organism - the lichen - totally different from either, has now been proved to be universal in these plants, and lichens are in all cases merely algae enmeshed in the interwoven hyphae of fungi (see Lichens).
Cells of this type are often called trumpet-hyphae (though they have no connection with the hyphae of Fungi), and in some genera of Laminariaceae those at the periphery of the medulla simulate the sieve-tubes of the higher plants in a striking degree, even (like these latter) developing the peculiar substance callose on or in the perforated cross-walls or sieve-plates.
In many forms its hyphae are particularly thick-walled, and may strikingly resemble the epidermis of a vascular plant.
The formation of a massive body naturally involves the localization of the absorptive region, and the function of absorption (which in the simpler forms is carried out by the whole of the vegetative part of the mycelium penetrating a solid or immersed in a liquid substratum) is subserved by the outgrowth of the hyphae of the surface-layer of that region into rhizoids, which, like those of the Algae living on soil, resemble the root-hairs of the higher plants.
The internal tissues, either consisting of obvious hyphae or of pseudoparenchyma, may also serve as a storehouse of plastic food substances.
Some make their way through the cells of the outer part of the cortex towards the root-tip, and form a mycelium or feltwork of hyphae, which generally occupies two or three layers of cells.
The mycelium of Sphaceloma grows just beneath the cuticle of the vine, through which it soon bursts, giving rise to a number of minute hyphae, which bear conidia.
The enclosed alga is protected by the threads (hyphae) of the fungus, and supplied with water and salts and, possibly, organic nitrogenous substances; in its turn the alga by means of its green or blue-green colouring matter and the sun's energy manufactures carbohydrates which are used in part by the fungus.