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Haustoria
In botany and mycology, a haustorium (plural haustoria) is a rootlike structure that grows into or around another structure to absorb water or nutrients. For example, in mistletoe or members of the broomrape family, the structure penetrates the host's tissue and draws nutrients from it. In mycology, it refers to the appendage or portion of a parasitic fungus (the hyphal tip), which performs a similar function. Microscopic haustoria penetrate the host plant's cell wall and siphon nutrients from the space between the cell wall and plasma membrane but do not penetrate the membrane itself. Larger (usually botanical, not fungal) haustoria do this at the tissue level. The etymology of the name corresponds to the Latin word ''haustor'' meaning ''the one who draws, drains or drinks'', and refers to the action performed by the outgrowth. In fungi Fungi in all major divisions form haustoria. Haustoria take several forms. Generally, on penetration, the fungus increases the surface ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haustorium DSC 5361 (28948051265)
In botany and mycology, a haustorium (plural haustoria) is a rootlike structure that grows into or around another structure to absorb water or nutrients. For example, in mistletoe or members of the broomrape family, the structure penetrates the host's tissue and draws nutrients from it. In mycology, it refers to the appendage or portion of a parasitic fungus (the hyphal tip), which performs a similar function. Microscopic haustoria penetrate the host plant's cell wall and siphon nutrients from the space between the cell wall and plasma membrane but do not penetrate the membrane itself. Larger (usually botanical, not fungal) haustoria do this at the tissue level. The etymology of the name corresponds to the Latin word ''haustor'' meaning ''the one who draws, drains or drinks'', and refers to the action performed by the outgrowth. In fungi Fungi in all major divisions form haustoria. Haustoria take several forms. Generally, on penetration, the fungus increases the surface area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orobanchaceae
Orobanchaceae, the broomrapes, is a family of mostly parasitic plants of the order Lamiales, with about 90 genera and more than 2000 species. Many of these genera (e.g., ''Pedicularis'', ''Rhinanthus'', ''Striga'') were formerly included in the family Scrophulariaceae ''sensu lato''. With its new circumscription, Orobanchaceae forms a distinct, monophyletic family. From a phylogenetic perspective, it is defined as the largest crown clade containing '' Orobanche major'' and relatives, but neither ''Paulownia tomentosa'' nor ''Phryma leptostachya'' nor '' Mazus japonicus''. The Orobanchaceae are annual herbs or perennial herbs or shrubs, and most (all except ''Lindenbergia'', ''Rehmannia'' and ''Triaenophora'') are parasitic on the roots of other plants—either holoparasitic or hemiparasitic (fully or partly parasitic). The holoparasitic species lack chlorophyll and therefore cannot perform photosynthesis. Description Orobanchaceae is the largest of the 20–28 dicot fami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungal Plant Pathogens And Diseases
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''true f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loranthaceae
Loranthaceae, commonly known as the showy mistletoes, is a family of flowering plants. It consists of about 75 genera and 1,000 species of woody plants, many of them hemiparasites. The three terrestrial species are ''Nuytsia floribunda'' (the Western Australian Christmas tree), ''Atkinsonia ligustrina'' (from the Blue Mountains of Australia), and '' Gaiadendron punctatum'' (from Central/South America.) Loranthaceae are primarily xylem parasites, but their haustoria may sometimes tap the phloem, while '' Tristerix aphyllus'' is almost holoparasitic. For a more complete description of the Australian Loranthaceae, seFlora of Australia online, for the Malesian Loranthaceae seFlora of Malesia Originally, Loranthaceae contained all mistletoe species, but the mistletoes of Europe and North America (''Viscum'', ''Arceuthobium'', and ''Phoradendron'') belong to the family Santalaceae. The APG II system 2003 assigns the family to the order Santalales in the clade core eudicots. Phylog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitism
Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted structurally to this way of life. The entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as Armillaria mellea, honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the Orobanchaceae, broomrapes. There are six major parasitic Behavioral ecology#Evolutionarily stable strategy, strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), wikt:trophic, trophicallytransmitted parasitism (by being eaten), Disease vector, vector-transmitted paras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyphal
A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one or more cells surrounded by a tubular cell wall. In most fungi, hyphae are divided into cells by internal cross-walls called "septa" (singular septum). Septa are usually perforated by pores large enough for ribosomes, mitochondria, and sometimes nuclei to flow between cells. The major structural polymer in fungal cell walls is typically chitin, in contrast to plants and oomycetes that have cellulosic cell walls. Some fungi have aseptate hyphae, meaning their hyphae are not partitioned by septa. Hyphae have an average diameter of 4–6 µm. Growth Hyphae grow at their tips. During tip growth, cell walls are extended by the external assembly and polymerization of cell wall components, and the internal production of new cell membrane. The S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cordyceps
''Cordyceps'' is a genus of ascomycete fungi (sac fungi) that includes about 600 species. Most ''Cordyceps'' species are endoparasitoids, parasitic mainly on insects and other arthropods (they are thus entomopathogenic fungi); a few are parasitic on other fungi. The generic name ''Cordyceps'' is derived from the Greek word κορδύλη ''kordýlē'', meaning "club", and the Greek word κεφαλή ''cephali'', meaning "head". The genus has a worldwide distribution and most of the approximately 600 species that have been described are from Asia (notably Nepal, China, Japan, Bhutan, Korea, Vietnam, and Thailand). ''Cordyceps'' species are particularly abundant and diverse in humid temperate and tropical jungles. Subtaxa There are two recognized subgenera: *''Cordyceps'' subgen. ''Cordyceps'' Fr. 1818 *''Cordyceps'' subgen. ''Cordylia'' Tul. & C. Tul. 1865 ''Cordyceps'' subgen. ''Epichloe'' was at one time a subgenus, but is now regarded as a separate genus, ''Epichloë''. ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flowering Plant
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants that produce their seeds enclosed within a fruit. They are by far the most diverse group of land plants with 64 orders, 416 families, approximately 13,000 known genera and 300,000 known species. Angiosperms were formerly called Magnoliophyta (). Like gymnosperms, angiosperms are seed-producing plants. They are distinguished from gymnosperms by characteristics including flowers, endosperm within their seeds, and the production of fruits that contain the seeds. The ancestors of flowering plants diverged from the common ancestor of all living gymnosperms before the end of the Carboniferous, over 300 million years ago. The closest fossil relatives of flowering plants are uncertain and contentious. The earliest angiosperm fossils ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endosperm
The endosperm is a tissue produced inside the seeds of most of the flowering plants following double fertilization. It is triploid (meaning three chromosome sets per nucleus) in most species, which may be auxin-driven. It surrounds the embryo and provides nutrition in the form of starch, though it can also contain oils and protein. This can make endosperm a source of nutrition in animal diet. For example, wheat endosperm is ground into flour for bread (the rest of the grain is included as well in whole wheat flour), while barley endosperm is the main source of sugars for beer production. Other examples of endosperm that forms the bulk of the edible portion are coconut "meat" and coconut "water", and corn. Some plants, such as orchids, lack endosperm in their seeds. Origin of endosperm Ancestral flowering plants have seeds with small embryos and abundant endosperm. The evolutionary development of flowering plants trends towards plants with mature seeds with little or no endosp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viscaceae
Viscaceae is a taxonomic family name of flowering plants. In this circumscription, the family includes the several genera of mistletoes. This family name is currently being studied and under review as in past decades, several systems of plant taxonomy recognized this family, notably the 1981 Cronquist system. However, the APG II system of 2003 does not recognize the family, treating it as a synonym of Santalaceae. This did not end the taxonomic debate among botanists and there are many that still think Viscaceae should be an accepted family name. According to the APG IV system Der and Nickrent (2008) found seven well supported clades in Santalaceae, but relationships between these clades are still poorly understood. The traditional and cultural uses of species within the Viscaceae merit further attention. Clades or genera treated as belonging to the currently debated family name Viscaceae include: *''Arceuthobium'' *''Dendrophthora'' *''Ginalloa'' *''Korthalsella'' *''Notothixos'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thallus
Thallus (plural: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. Many of these organisms were previously known as the thallophytes, a polyphyletic group of distantly related organisms. An organism or structure resembling a thallus is called thalloid, thallodal, thalliform, thalline, or thallose. A thallus usually names the entire body of a multicellular non-moving organism in which there is no organization of the tissues into organs. Even though thalli do not have organized and distinct parts (leaves, roots, and stems) as do the vascular plants, they may have analogous structures that resemble their vascular "equivalents". The analogous structures have similar function or macroscopic structure, but different microscopic structure; for example, no thallus has vascular tissue. In exceptional cases such as the Lemnoideae, where ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron
The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no known components or substructure. The electron's mass is approximately 1/1836 that of the proton. Quantum mechanical properties of the electron include an intrinsic angular momentum ( spin) of a half-integer value, expressed in units of the reduced Planck constant, . Being fermions, no two electrons can occupy the same quantum state, in accordance with the Pauli exclusion principle. Like all elementary particles, electrons exhibit properties of both particles and waves: They can collide with other particles and can be diffracted like light. The wave properties of electrons are easier to observe with experiments than those of other particles like neutrons and protons because electrons have a lower mass and hence a longer de Broglie wavele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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