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98-776: Moniliopsis Ruhland (1908) Thanatephorus Donk (1956) Uthatobasidium Donk (1956) Koleroga Donk (1958) Cejpomyces Svrcek & Pouzar (1970) Oncobasidium Talbot & Keane (1971) Ypsilondium Donk (1972) Aquathanatephorus Tu & Kimbrough (1978) Ceratorhiza R.T. Moore (1987) Rhizoctonia is a genus of fungi in the order Cantharellales . Species form thin, effused, corticioid basidiocarps (fruit bodies), but are most frequently found in their sterile, anamorphic state. Rhizoctonia species are saprotrophic , but some are also facultative plant pathogens , causing commercially important crop diseases . Some are also endomycorrhizal associates of orchids . The genus name

196-471: A stem , which is floating by means of buoyant bulb-like nodules at its base above the water surface. They have long, spongy, bulbous stalks. The feathery, freely hanging roots are purple-black. An erect stalk supports a single spike of 8–15 conspicuously attractive flowers , mostly lavender to pink in colour with six petals. When not in bloom, water hyacinth may be mistaken for frogbit ( Limnobium spongia ) or Amazon frogbit ( Limnobium laevigatum ). One of

294-456: A 12-month period. It is, however, costly and requires the use of both land and water vehicles, but many years were needed for the lake to become in poor condition, and reclamation will be a continual process. It can have an annual cost from $ 6 million to $ 20 million and is only considered a short-term solution to a long-term problem. Another disadvantage with mechanical harvesting is that it can lead to further fragmentation of water hyacinths when

392-601: A bold solution was put forth by the New Foods Society . Their plan was to import and release hippopotamus from Africa into the rivers and bayous of Louisiana. The hippopotamus would then eat the water hyacinth and also produce meat to solve another serious problem at the time, the American meat crisis. Known as the American Hippo Bill, H.R. 23621 was introduced by Louisiana Congressman Robert Broussard and debated by

490-474: A capacity of 40 m , per day, for 365 days to get rid of it. The water hyacinth would then be transferred to a dumping site and allowed to decompose, which releases CO 2 , methane , and nitrogen oxides. Water hyacinth has been widely introduced in North America, Europe, Asia, Australia, Africa, and New Zealand . In many areas, it has become an important and pernicious invasive species . In New Zealand, it

588-427: A hundredfold in number in a matter of 23 days. In their native range, the flowers are pollinated by long-tongued bees, and the plants can reproduce both sexually and clonally. The invasiveness of the hyacinth is related to its ability to clone itself, and large patches are likely to all be part of the same genetic form. Water hyacinth has three flower morphs and is termed " tristylous ". The flower morphs are named for

686-643: A later homonym of a validly published name is a nomen illegitimum or nom. illeg. ; for a full list refer to the International Code of Nomenclature for algae, fungi, and plants and the work cited above by Hawksworth, 2010. In place of the "valid taxon" in zoology, the nearest equivalent in botany is " correct name " or "current name" which can, again, differ or change with alternative taxonomic treatments or new information that results in previously accepted genera being combined or split. Prokaryote and virus codes of nomenclature also exist which serve as

784-621: A long time and redescribed as new by a range of subsequent workers, or if a range of genera previously considered separate taxa have subsequently been consolidated into one. For example, the World Register of Marine Species presently lists 8 genus-level synonyms for the sperm whale genus Physeter Linnaeus, 1758, and 13 for the bivalve genus Pecten O.F. Müller, 1776. Within the same kingdom, one generic name can apply to one genus only. However, many names have been assigned (usually unintentionally) to two or more different genera. For example,

882-401: A matter of concern, stating that the crew of the spraying boat would routinely catch fish from their working areas and consume them. However, spraying had little hope of completely eradicating the water hyacinth, due to the vastness of escaped colonies and the inaccessibility of some of the infested areas, and the engineer suggested that some biological means of control may be needed. In 1910,

980-427: A package of those seeds. One paper has also inquired into the role which catalog sales of seeds and plants may have played in the dissemination of invasive plants. P. crassipes was found to have been offered in the 1884 issue of Bordentown, New Jersey –based Edmund D. Sturtevant's Catalogue of Rare Water Lilies and Other Choice Aquatic Plants , and Haage & Schmidt  [ de ] of Germany has offered

1078-527: A piece penned in 1941 by the director of the wildlife and fisheries division at the Louisiana Department of Conservation, where the author writes, "the Japanese government maintained a Japanese building" at the fair, and the "Japanese staff imported from Venezuela considerable numbers of water hyacinth, which were given away as souvenirs". The claim has been repeated by later writers, with various shifts in

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1176-409: A reference for designating currently accepted genus names as opposed to others which may be either reduced to synonymy, or, in the case of prokaryotes, relegated to a status of "names without standing in prokaryotic nomenclature". An available (zoological) or validly published (botanical) name that has been historically applied to a genus but is not regarded as the accepted (current/valid) name for

1274-406: A researcher devoted to the study of the plant has discovered that ukiyo-e artist Utagawa Kunisada (or Utagawa Toyokuni III, d. 1865 ) produced a wood-block print featuring the water hyacinth, goldfish, and beautiful women , dated to 1855. The plant is floated on the water surface of filled (glassware) fishbowls or glazed earthenware waterlily pots ( hibachi pots serving as substitute). In

1372-621: A serious problem on Lake Tana in Ethiopia. The water hyacinth is also present on the Shire River in the Liwonde National Park in Malawi. The water hyacinth was introduced to Bengal , India, because of its ornamental flowers and shapes of leaves, but became an invasive weed, draining oxygen from the water bodies and resulting in devastation of fish stocks. The water hyacinth was referred to as

1470-565: A species resembling Thanatephorus , but having septate basidiospores . Based on their similar morphology, the genera were considered synonymous by Langer (1994). In 1971 Talbot & Keane introduced the genus Oncobasidium for a plant pathogenic species resembling Thanatephorus but lacking sclerotia and in 1972 M.A. Donk introduced the genus Ypsilondium for a species resembling Uthatobasidium but having bisterigmate (two-spored) basidia. Both genera were considered synonyms of Thanatephorus by Roberts (1999). In 1978 Tu & Kimbrough introduced

1568-427: A taxon; however, the names published in suppressed works are made unavailable via the relevant Opinion dealing with the work in question. In botany, similar concepts exist but with different labels. The botanical equivalent of zoology's "available name" is a validly published name . An invalidly published name is a nomen invalidum or nom. inval. ; a rejected name is a nomen rejiciendum or nom. rej. ;

1666-455: A total of c. 520,000 published names (including synonyms) as at end 2019, increasing at some 2,500 published generic names per year. "Official" registers of taxon names at all ranks, including genera, exist for a few groups only such as viruses and prokaryotes, while for others there are compendia with no "official" standing such as Index Fungorum for fungi, Index Nominum Algarum and AlgaeBase for algae, Index Nominum Genericorum and

1764-829: A wide range of commercially significant plant diseases. It is one of the fungi responsible for Brown patch (a turfgrass disease), damping off in seedlings, as well as black scurf of potatoes , bare patch of cereals , root rot of sugar beet , belly rot of cucumber , sheath blight of rice , and many other pathogenic conditions. Rhizoctonia oryzae-sativae causes 'aggregate sheath spot' and 'sclerotium' disease of rice. The subtropical Rhizoctonia noxia causes 'black rot' of coffee and other foliar blights, whilst Rhizoctonia theobromae causes 'vascular-streak dieback' of Theobroma cacao (cocoa tree). In Europe, Rhizoctonia butinii causes web blight of spruce. An efficient conversion of tryptophan to indole-3-acetic acid (IAA) and/or tryptophol can be achieved by some species in

1862-466: Is a liquid bromide salt that can rapidly penetrate the leaves of the water hyacinth and lead to immediate inactivity of plant cells and cellular processes. The herbicide glyphosate has a lower toxicity than the other herbicides, so takes longer for the water hyacinth mats to be destroyed (about three weeks). The symptoms include steady wilting of the plants and a yellow discoloration of the plant leaves that eventually leads to plant decay. Physical control

1960-596: Is discouraged by both the International Code of Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants , there are some five thousand such names in use in more than one kingdom. For instance, A list of generic homonyms (with their authorities), including both available (validly published) and selected unavailable names, has been compiled by the Interim Register of Marine and Nonmarine Genera (IRMNG). The type genus forms

2058-408: Is greater than 15% that of sea water (around 5 g salt per kg). In brackish water , its leaves show epinasty and chlorosis , and eventually die. Rafts of harvested water hyacinth have been floated to the sea , which kills it. Azotobacter chroococcum , a species of nitrogen-fixing bacteria , is probably concentrated around the bases of the petioles , but the bacteria do not fix nitrogen unless

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2156-422: Is limited. These organisms regulate water hyacinth by limiting its size, vegetative propagation, and seed production. They also carry microorganisms that can be pathological to the water hyacinth. These weevils eat stem tissue, which results in a loss of buoyancy for the plant, which will eventually sink. Although meeting with limited success, the weevils have since been released in many other countries. However,

2254-723: Is listed on the National Pest Plant Accord , which prevents it from being propagated, distributed, or sold. In large water areas such as Louisiana, the Kerala Backwaters in India , Tonlé Sap in Cambodia , and Lake Victoria , it has become a serious pest. The common water hyacinth has become an invasive plant species on Lake Victoria in Africa after it was introduced into the area in the 1980s. A 1.22 Gb/8 chromosome reference genome

2352-508: Is now conserved as R. solani under the International Code of Nomenclature for algae, fungi, and plants . R.T. Moore retained species having teleomorphs in the genus Thanatephorus within Rhizoctonia , but moved those with teleomorphs in the genus Ceratobasidium to the new anamorphic genus Ceratorhiza . In 1956, Dutch mycologist M.A. Donk published the new teleomorphic genera Thanatephorus and Uthatobasidium simultaneously, reserving

2450-428: Is performed by land-based machines, such as bucket cranes, draglines, or boom, or by water-based machinery such as aquatic weed harvesters , dredges , or vegetation shredder. Mechanical removal is seen as the best short-term solution to the proliferation of the plant. A project on Lake Victoria in Africa used various pieces of equipment to chop, collect, and dispose of 1,500 hectares (3,700 acres) of water hyacinth in

2548-533: Is rearing M. scutellaris and the water hyacinth weevils N. eichhorniae and N. bruchi en masse for biological control at dams in South Africa, including the Hartbeespoort Dam . The moth Niphograpta albiguttalis (Warren) (Lepidoptera: Pyralidae) has been introduced to North America, Africa, and Australia. Larvae of this moth bore in the stems and flower buds of water hyacinth. Since water hyacinth

2646-460: Is somewhat arbitrary. Although all species within a genus are supposed to be "similar", there are no objective criteria for grouping species into genera. There is much debate among zoologists about whether enormous, species-rich genera should be maintained, as it is extremely difficult to come up with identification keys or even character sets that distinguish all species. Hence, many taxonomists argue in favor of breaking down large genera. For instance,

2744-474: Is the type species , and the generic name is permanently associated with the type specimen of its type species. Should the specimen turn out to be assignable to another genus, the generic name linked to it becomes a junior synonym and the remaining taxa in the former genus need to be reassessed. In zoological usage, taxonomic names, including those of genera, are classified as "available" or "unavailable". Available names are those published in accordance with

2842-522: Is the causal agent of violet root rot of carrots and other root vegetables. Subsequent authors added over 100 additional names to the genus, most of them plant pathogens bearing only a superficial resemblance to the type species . Rhizoctonia thus became an artificial form genus of anamorphic fungi comprising a diverse range of unrelated species. As part of a move towards a more natural classification of fungi, American mycologist Royall T. Moore proposed in 1987 that Rhizoctonia should be restricted to

2940-419: Is the least used of the three controls of water hyacinth, because of its long-term effects on the environment and human health. The use of herbicides requires strict approval from governmental protection agencies and skilled technicians to handle and spray the affected areas. The use of chemical herbicides is only used in case of severe infiltration of water hyacinth. However, the most successful use of herbicides

3038-492: Is the sole species of the subgenus Oshunae within the genus Pontederia . Anecdotally, it is known as the "terror of Bengal" due to its invasive growth tendencies. Water hyacinth is a free-floating perennial aquatic plant (or hydrophyte) native to tropical and subtropical South America. With broad, thick, glossy, ovate leaves, water hyacinth may rise above the surface of the water as much as 1 m (3 ft) in height. The leaves are 10–20 cm (4–8 inches) across on

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3136-416: Is when it is used for smaller areas of infestation, because in larger areas, more mats of water hyacinths are likely to survive the herbicides and can fragment to further propagate a large area of water hyacinth mats. In addition, it is more cost-effective and less laborious than mechanical control, yet it can lead to environmental effects, as it can penetrate into the ground water system and can affect not only

3234-621: The International Code of Zoological Nomenclature ; the earliest such name for any taxon (for example, a genus) should then be selected as the " valid " (i.e., current or accepted) name for the taxon in question. Consequently, there will be more available names than valid names at any point in time; which names are currently in use depending on the judgement of taxonomists in either combining taxa described under multiple names, or splitting taxa which may bring available names previously treated as synonyms back into use. "Unavailable" names in zoology comprise names that either were not published according to

3332-799: The International Plant Names Index for plants in general, and ferns through angiosperms, respectively, and Nomenclator Zoologicus and the Index to Organism Names for zoological names. Totals for both "all names" and estimates for "accepted names" as held in the Interim Register of Marine and Nonmarine Genera (IRMNG) are broken down further in the publication by Rees et al., 2020 cited above. The accepted names estimates are as follows, broken down by kingdom: The cited ranges of uncertainty arise because IRMNG lists "uncertain" names (not researched therein) in addition to known "accepted" names;

3430-635: The United States Army Corps of Engineers to solve the water hyacinth problem plaguing Gulf states such as Florida and Louisiana. Thus, in the early 20th century, the U.S. War Department (i.e., the Army Corps of Engineers) tested various means of eradicating the plants, including the jet-streaming of steam and hot water, application of various strong acids , and application of petroleum followed by incineration. Spraying with saturated salt solution (but not dilute solutions) effectively killed

3528-457: The family Ceratobasidiaceae . The genus is only monophyletic , however, if species of Ceratobasidium (excluding the type) and Ceratorhiza are included as synonyms, since there is no apparent distinction between these species and species of Rhizoctonia . DNA sequencing has also confirmed the synonymy of Uthatobasidium , Oncobasidium , and Koleroga . Following changes to the International Code of Nomenclature for algae, fungi, and plants ,

3626-419: The nomenclature codes , which allow each species a single unique name that, for animals (including protists ), plants (also including algae and fungi ) and prokaryotes ( bacteria and archaea ), is Latin and binomial in form; this contrasts with common or vernacular names , which are non-standardized, can be non-unique, and typically also vary by country and language of usage. Except for viruses ,

3724-404: The platypus belongs to the genus Ornithorhynchus although George Shaw named it Platypus in 1799 (these two names are thus synonyms ) . However, the name Platypus had already been given to a group of ambrosia beetles by Johann Friedrich Wilhelm Herbst in 1793. A name that means two different things is a homonym . Since beetles and platypuses are both members of the kingdom Animalia,

3822-420: The type species and its relatives, with unrelated species moved to other genera. Unfortunately, this meant that the best-known but unrelated species, Rhizoctonia solani , would have undergone a name change to Moniliopsis solani . To avoid this, it was subsequently proposed that R. solani should replace R. crocorum as the type species of Rhizoctonia . This proposal was passed and the type of Rhizoctonia

3920-626: The "(beautiful) blue devil" in Bengal and "Bengal terror" elsewhere in India; it was called "German weed" (Bengali: Germani pana ) in Bangladesh out of belief the German Kaiser submarine mission was involved in introducing them at the outbreak of World War I. Concerted efforts were made to eradicate water hyacinths, which affected navigability in Bengal's rivers. The Bengal Water Hyacinth Act, 1936 prohibited

4018-643: The 1930s, water hyacinth was introduced into China as a feed , ornamental plant , and sewage -control plant, and it was widely planted in the south as an animal feed. Beginning in the 1980s, with the rapid development of China's inland industry, the eutrophication of inland waters has intensified. With the help of its efficient asexual reproduction and environmental adaptation mechanisms, water hyacinth began to spread widely in river basins. The hyacinths has blocked rivers and hindered water traffic. For example, many waterways in Zhejiang and other provinces have been blocked by

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4116-582: The Agricultural Committee of the U.S. House of Representatives. The chief collaborators in the New Foods Society and proponents of Broussard's bill were Major Frederick Russell Burnham , the celebrated American Scout , and Captain Fritz Duquesne , a South African Scout who later became a notorious spy for Germany. Presenting before the Agricultural Committee, Burnham made the point that none of

4214-566: The European Union banned any sales of the water hyacinth in the EU. The species features on the list of Invasive Alien Species of Union Concern. This means that not only the sales but also importation, cultivation, or intentional release into the environment are forbidden in the whole of the European Union. In Papua New Guinea , water hyacinth blocks sunlight to other aquatic organisms, creates habitat for malaria-carrying mosquitoes, clogs waterways to

4312-699: The animals that Americans ate (chickens, pigs, cattle, sheep, or lambs) were native to the U.S. and had all been imported by European settlers centuries before, so Americans should not hesitate to introduce hippopotamus and other large animals into the American diet. Duquesne, who was born and raised in South Africa, further noted that European settlers on that continent commonly included hippopotamus, ostrich, antelope, and other African wildlife in their diets and suffered no ill effects. The American Hippo Bill fell one vote short of passage. Water hyacinths have also been introduced into waters inhabited by manatees in Florida, for

4410-442: The base for higher taxonomic ranks, such as the family name Canidae ("Canids") based on Canis . However, this does not typically ascend more than one or two levels: the order to which dogs and wolves belong is Carnivora ("Carnivores"). The numbers of either accepted, or all published genus names is not known precisely; Rees et al., 2020 estimate that approximately 310,000 accepted names (valid taxa) may exist, out of

4508-500: The bottom of the water, causing secondary pollution to the water body, destroying the natural water quality, and may even affect the quality of residents' drinking water in severe cases. Water where water hyacinth grows heavily is often a breeding place for disease vectors (e.g. mosquitoes and snails ) and harmful pathogens, posing a potential threat to the health of local residents. It is very critical to monitor areas quickly that are infested in order to efficiently reduce or control

4606-546: The cultivation of the plants. By 1947, the problem was resolved, and navigability was restored to the rivers, although the plants still exist in wetlands. Water hyacinths were called "Japanese trouble" in Sri Lanka because there was a rumor that the British had planted them to entice Japanese aircraft to land on the insecure pads. The plant entered Japan in 1884 for horticultural appreciation, according to conventional wisdom, but

4704-577: The details. Thus National Academy of Sciences fellow Noel D. Vietmeyer (1975) wrote that "Japanese entrepreneurs" introduced the plant into the U.S., and the plants had been "collected from the Orinoco River in Venezuela." This claim was echoed by a pair of NASA researchers ( Wolverton & McDonald 1979 ), who asserted that the souvenir plants were carelessly dumped in various waterways. Canadian biologist Spencer C. H. Barrett (2004) meanwhile favored

4802-402: The effects of the biological control agent in extensive host-range studies since 2006 and concluded that the insect is highly host-specific and will not pose a threat to any other plant population other than the targeted water hyacinth. Researchers also hope that this biological control will be more resilient than existing biological controls and the herbicides that are already in place to combat

4900-489: The environment. Therefore, the process is very time-intensive. As chemical and mechanical removals are often too expensive, polluting, and ineffective, researchers have turned to biological control agents to deal with water hyacinth. The effort began in the 1970s, when USDA researchers released into the United States three species of weevils known to feed on water hyacinth, Neochetina bruchi , N. eichhorniae , and

4998-441: The fastest-growing plants known, water hyacinth reproduces primarily by way of runners or stolons , which eventually form daughter plants. Each plant additionally can produce thousands of seeds each year, and these seeds can remain viable for more than 28 years. Common water hyacinths are vigorous growers, and mats can double in size in one to two weeks. In terms of plant count rather than size, they are said to multiply by more than

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5096-446: The form "author, year" in zoology, and "standard abbreviated author name" in botany. Thus in the examples above, the genus Canis would be cited in full as " Canis Linnaeus, 1758" (zoological usage), while Hibiscus , also first established by Linnaeus but in 1753, is simply " Hibiscus L." (botanical usage). Each genus should have a designated type , although in practice there is a backlog of older names without one. In zoology, this

5194-424: The former for plant-pathogenic species producing sclerotia-bearing Rhizoctonia anamorphs (with T. cucumeris as the type) and the latter for saprotrophic species not producing anamorphs (with U. fusisporum as the type). In 1996, on the basis of their similar morphology, the two genera were considered to be synonymous by K. Hauerslev and P. Roberts. in 1970 Svrček & Pouzar introduced the genus Cejpomyces for

5292-727: The generic name (or its abbreviated form) still forms the leading portion of the scientific name, for example, Canis lupus lupus for the Eurasian wolf subspecies, or as a botanical example, Hibiscus arnottianus ssp. immaculatus . Also, as visible in the above examples, the Latinised portions of the scientific names of genera and their included species (and infraspecies, where applicable) are, by convention, written in italics . The scientific names of virus species are descriptive, not binomial in form, and may or may not incorporate an indication of their containing genus; for example,

5390-428: The genus Aquathanatephorus for an isolate from water hyacinth which produced a teleomorph with swollen, inwardly curving sterigmata . This was redetermined as Thanatephorus cucumeris by Andersen (1996). Ceratobasidium was introduced in 1935 by American mycologist D.P. Rogers to accommodate species of the old form genus Corticium that showed affinities with the heterobasidiomycetes . These affinities were

5488-469: The genus Rhizoctonia . Genus The composition of a genus is determined by taxonomists . The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: Moreover, genera should be composed of phylogenetic units of

5586-504: The growth of these species. On the other hand, water hyacinth can also provide a food source for goldfish, keep water clean and help to provide oxygen. The invasion of water hyacinth also has socioeconomic consequences. Since water hyacinth is composed of up to 95% water, its evapotranspiration rate is high. As such, small lakes that have been covered with the species can dry out and leave communities without adequate water or food supply. In some areas, dense mats of water hyacinth prevent

5684-464: The hydrological cycle within an ecosystem, but also negatively affect the local water system and human health. Also of note, the use of herbicides is not strictly selective of water hyacinths; keystone species and vital organisms such as microalgae can perish from the toxins and can disrupt fragile food webs. The chemical regulation of water hyacinths can be done using common herbicides such as 2,4-D, glyphosate , and diquat. The herbicides are sprayed on

5782-467: The introduced range. Further, the genomic study also revealed the adaptation in four key pathways; plant-pathogen interaction, plant-hormone signal transduction, photosynthesis and abiotic stress tolerance, which provide water hyacinth to expand its niche and compete with other native flora Various accounts are given as to how the water hyacinth was introduced to the United States . The claim that

5880-426: The invasive water hyacinth. Another insect being considered as a biological control agent is the semiaquatic grasshopper Cornops aquaticum . This insect is specific to the water hyacinth and its family, and besides feeding on the plant, it introduces a secondary pathogenic infestation. This grasshopper has been introduced into South Africa in controlled trials. The Rhodes University Centre for Biological Control

5978-628: The largest component, with 23,236 ± 5,379 accepted genus names, of which 20,845 ± 4,494 are angiosperms (superclass Angiospermae). By comparison, the 2018 annual edition of the Catalogue of Life (estimated >90% complete, for extant species in the main) contains currently 175,363 "accepted" genus names for 1,744,204 living and 59,284 extinct species, also including genus names only (no species) for some groups. The number of species in genera varies considerably among taxonomic groups. For instance, among (non-avian) reptiles , which have about 1180 genera,

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6076-586: The late 18th to early 19th century during Muhammad Ali of Egypt 's era, but was not recognized as an invasive threat until 1879. The invasion into Egypt is dated between 1879 and 1892 by Brij Gopal . The plant (Afrikaans: waterhiasint ) arguably invaded South Africa in 1910, although earlier dates have been claimed. A waterbody extensively threatened by water hyacinth is the Hartebeespoort Dam near Brits in North West Province . The plant

6174-565: The length of their pistils: long (L), medium (M), and short (S). Tristylous populations are, however, limited to the native lowland South American range of water hyacinth; in the introduced range, the M-morph prevails, with the L-morph occurring occasionally and the S-morph is absent altogether. This geographical distribution of the floral morphs indicates that founder events have played a prominent role in

6272-433: The lizard genus Anolis has been suggested to be broken down into 8 or so different genera which would bring its ~400 species to smaller, more manageable subsets. Water hyacinth Pontederia crassipes (formerly Eichhornia crassipes ), commonly known as common water hyacinth , is an aquatic plant native to South America , naturalized throughout the world, and often invasive outside its native range. It

6370-403: The most (>300) have only 1 species, ~360 have between 2 and 4 species, 260 have 5–10 species, ~200 have 11–50 species, and only 27 genera have more than 50 species. However, some insect genera such as the bee genera Lasioglossum and Andrena have over 1000 species each. The largest flowering plant genus, Astragalus , contains over 3,000 species. Which species are assigned to a genus

6468-448: The most effective control method remains the control of excessive nutrients and prevention of the spread of this species. In May 2010, the USDA's Agricultural Research Service released Megamelus scutellaris as an additional biological control insect for the invasive water hyacinth species. M. scutellaris is a small planthopper insect native to Argentina. Researchers have been studying

6566-428: The name could not be used for both. Johann Friedrich Blumenbach published the replacement name Ornithorhynchus in 1800. However, a genus in one kingdom is allowed to bear a scientific name that is in use as a generic name (or the name of a taxon in another rank) in a kingdom that is governed by a different nomenclature code. Names with the same form but applying to different taxa are called "homonyms". Although this

6664-843: The plant is suffering extreme nitrogen deficiency. Fresh plants contain prickly crystals . This plant is reported to contain hydrogen cyanide , alkaloids , and triterpenoids , and may induce itching . Plants sprayed with 2,4-dichlorophenoxyacetic acid (2,4-D) may accumulate lethal doses of nitrates and other harmful elements in polluted environments . Water hyacinth grows and reproduces quickly, so it can cover large portions of ponds and lakes. It can easily coexist with other invasive plants and native plants in an area. Particularly vulnerable are bodies of water that have already been affected by human activities, such as artificial reservoirs or eutrophied lakes that receive large amounts of nutrients. It outcompetes native aquatic plants, both floating and submerged. In 2011, Wu Fuqin et al. tracked

6762-446: The plant since 1864 (when the firm was founded). By 1895, it was offered by seed purveyors in the states of New Jersey, New York, California, and Florida. Harper's Weekly magazine (1895) printed an anecdotal account stating that a certain man from New Orleans collected and brought home water hyacinths from Colombia, around 1892, and the plant proliferated in a matter of 2 years. As the hyacinths multiply into mats, they eliminate

6860-413: The plant's propensity for absorbing contaminants, and it is considered toxic to humans. Furthermore, the practice of mechanical harvesting is not effective in large-scale infestations, because this aquatic invasive species grows much more rapidly than it can be eliminated. Only one to two acres ( 1 ⁄ 2 to 1 ha) of water hyacinth can be mechanically harvested daily because of the vast amounts in

6958-410: The plants are broken up by spinning cutters of the plant-harvesting machinery. The fragments of water hyacinth that are left behind in the water can easily reproduce asexually and cause another infestation. Transportation and disposal of the harvested water hyacinth is a challenge, though, because the vegetation is heavy in weight. The harvested water hyacinth can pose a health risk to humans because of

7056-401: The plants; unfortunately this was considered prohibitively expensive, and the engineers selected Harvesta brand herbicide, whose active ingredient was arsenic acid , as the optimal cost-effective tool for eradication. This herbicide was used until 1905, when it was substituted with a different, white arsenic –based compound. An engineer charged with the spraying did not think the poison to be

7154-477: The point that boats cannot get through, and reduces the quality of water for purposes such as cooking, washing, and drinking. People have lost income or even died due to being unable to travel to get food or medical care, or due to diseases from contaminated water or mosquitoes. Control depends on the specific conditions of each affected location such as the extent of water hyacinth infestation, regional climate, and proximity to human and wildlife. Chemical control

7252-574: The possession of large sterigmata ("cerato-basidium" means "horned basidium ") and the production of basidiospores that produce secondary spores. The genus Koleroga was proposed by Donk (1958) to accommodate K. noxia , a plant pathogen morphologically similar to Ceratobasidium but not known to produce secondary spores. Talbot (1965) demonstrated that such spores were present in some collections and suggested that Koleroga be synonymized with Ceratobasidium . Molecular research, based on cladistic analysis of DNA sequences , places Rhizoctonia within

7350-489: The practice of giving different names to teleomorph and anamorph forms of the same fungus was discontinued, meaning that Thanatephorus became a synonym of the earlier name Rhizoctonia . In its current sense, therefore, the genus Rhizoctonia includes both anamorphic and teleomorphic fungi. Not all species referred to Ceratobasidium or Thanatephorus have yet been combined in Rhizoctonia , however. A comprehensive survey and redisposition of old species names in Rhizoctonia

7448-443: The presence of fish, and choke waterways for boating and shipping. This effect was well underway in the state of Louisiana by the turn of the 20th century. The plant invaded Florida in 1890, and an estimated 50 kg/m of the plant mass choked Florida's waterways. The clogging of the St. Johns River was posing a serious threat, and in 1897 the government dispatched a task force of

7546-526: The provisions of the ICZN Code, e.g., incorrect original or subsequent spellings, names published only in a thesis, and generic names published after 1930 with no type species indicated. According to "Glossary" section of the zoological Code, suppressed names (per published "Opinions" of the International Commission of Zoological Nomenclature) remain available but cannot be used as the valid name for

7644-514: The purpose of bioremediation (cf. §Phytoremediation below) of the waters that have become contaminated and fallen victim to algal blooming . The manatees include the water hyacinth in their diet, but it may not be the food of first choice for them. In 1956, E. crassipes was banned for sale or shipment in the United States, subject to a fine and/or imprisonment. This law was repealed by HR133 [116th Congress (2019–2020)] on 12/27/2020. The water hyacinth may have been introduced into Egypt in

7742-436: The rapidly growing water hyacinth. In addition, a large number of water hyacinths floating in the water block sunlight from entering the water, and its decay consumes dissolved oxygen in the water, pollutes water quality, and can kill other aquatic plants. The outbreak of water hyacinth has seriously affected the biodiversity of the local ecosystem and threatened the production, life, and health of community residents. In 2016,

7840-407: The results of Yunnan Dianchi Lake and also showed that water hyacinth could affect the photosynthesis of phytoplankton, submerged plants, and algae by water environment quality and inhibit their growth. The decay process depletes dissolved oxygen in the water, often killing fish. Water hyacinth can absorb a large amount of harmful heavy metals and other substances. After death, it rots and sinks to

7938-466: The same kind as other (analogous) genera. The term "genus" comes from Latin genus , a noun form cognate with gignere ('to bear; to give birth to'). The Swedish taxonomist Carl Linnaeus popularized its use in his 1753 Species Plantarum , but the French botanist Joseph Pitton de Tournefort (1656–1708) is considered "the founder of the modern concept of genera". The scientific name (or

8036-408: The scientific epithet) of a genus is also called the generic name ; in modern style guides and science, it is always capitalised. It plays a fundamental role in binomial nomenclature , the system of naming organisms , where it is combined with the scientific name of a species : see Botanical name and Specific name (zoology) . The rules for the scientific names of organisms are laid down in

8134-406: The species' worldwide spread. Its habitat ranges from tropical desert to subtropical or warm, temperate desert to rainforest zones. The temperature tolerance of the water hyacinth is: Its pH tolerance is estimated at 5.0–7.5. Leaves are killed by frost and plants do not tolerate water temperatures more than 34 °C (93 °F). Water hyacinths do not grow where the average salinity

8232-497: The specific name particular to the wolf. A botanical example would be Hibiscus arnottianus , a particular species of the genus Hibiscus native to Hawaii. The specific name is written in lower-case and may be followed by subspecies names in zoology or a variety of infraspecific names in botany . When the generic name is already known from context, it may be shortened to its initial letter, for example, C. lupus in place of Canis lupus . Where species are further subdivided,

8330-412: The standard format for a species name comprises the generic name, indicating the genus to which the species belongs, followed by the specific epithet, which (within that genus) is unique to the species. For example, the gray wolf 's scientific name is Canis lupus , with Canis ( Latin for 'dog') being the generic name shared by the wolf's close relatives and lupus (Latin for 'wolf') being

8428-403: The taxon is termed a synonym ; some authors also include unavailable names in lists of synonyms as well as available names, such as misspellings, names previously published without fulfilling all of the requirements of the relevant nomenclatural code, and rejected or suppressed names. A particular genus name may have zero to many synonyms, the latter case generally if the genus has been known for

8526-400: The theory they were first cultivated in garden ponds, after which they multiplied and escaped to the environs. The account gains different details as told by children's story-teller Carole Marsh (1992), who says "Japan gave away water hyacinth seeds" during the exposition, and another Southern raconteur, Gaspar J. "Buddy" Stall (1998), assured his readership that the Japanese gave each family

8624-412: The use of a waterway, leading to the loss of transportation (both human and cargo), as well as a loss of fishing possibilities. Large sums of money are allocated to the removal of water hyacinth from the water bodies as well as figuring out how to destroy the remains harvested. Harvesting water hyacinth mechanically requires considerable effort. A million tons of fresh biomass would require 75 trucks with

8722-566: The values quoted are the mean of "accepted" names alone (all "uncertain" names treated as unaccepted) and "accepted + uncertain" names (all "uncertain" names treated as accepted), with the associated range of uncertainty indicating these two extremes. Within Animalia, the largest phylum is Arthropoda , with 151,697 ± 33,160 accepted genus names, of which 114,387 ± 27,654 are insects (class Insecta). Within Plantae, Tracheophyta (vascular plants) make up

8820-429: The virus species " Salmonid herpesvirus 1 ", " Salmonid herpesvirus 2 " and " Salmonid herpesvirus 3 " are all within the genus Salmonivirus ; however, the genus to which the species with the formal names " Everglades virus " and " Ross River virus " are assigned is Alphavirus . As with scientific names at other ranks, in all groups other than viruses, names of genera may be cited with their authorities, typically in

8918-474: The water hyacinth borer Sameodes albiguttalis . The weevil species were introduced into the Gulf Coast states, such as Louisiana, Texas, and Florida, where thousands of acres were infested by water hyacinth. A decade later, a decrease was found in water hyacinth mats by as much as 33%, but because the lifecycle of the weevils is 90 days, the use of biological predation to efficiently suppress water hyacinth growth

9016-552: The water hyacinth leaves and leads to direct changes to the physiology of the plant. The use of the herbicide known as 2,4-D leads to the death of water hyacinth through inhibition of cell growth of new tissue and cellular apoptosis. Almost a two-week period may be needed before mats of water hyacinth are destroyed with 2, 4-D. Between 75,000 and 150,000 acres (30,000 and 61,000 ha) of water hyacinth and alligator weed are treated annually in Louisiana. The herbicide known as diquat

9114-632: The water hyacinth was introduced to the U.S. in 1884 at the World's Fair in New Orleans , also known as the World Cotton Centennial , has been characterized as the "first authentic account", as well as "local legend". At some point, a legend arose that the plants had been given away as a gift by a Japanese delegation at the fair. This claim is absent in a pertinent article published in a military engineer's trade journal dating to 1940, but appears in

9212-587: Was assembled to study nuclear and chloroplast genomes between 10 water hyacinth lines from 3 continents. Results indicating the spread of a limited genotype of water hyacinth from South America, where it has the highest genetic diversity. The paper proposing the spread potentially originating from ships travelling from Itajaí Port on the Brazilian East Coast. Although genetic studies on samples from Bangladesh and Indonesia demonstrate different genotypes, potentially implicating multiple introductions to

9310-686: Was first reported in 1965 at the Koka Reservoir and in the Awash River , where the Ethiopian Electric Light and Power Authority has managed to bring it under moderate control at considerable cost of human labor. Other infestations in Ethiopia include many bodies of water in the Gambela Region , the Blue Nile from Lake Tana into Sudan , and Lake Ellen near Alem Tena . By 2018, it has become

9408-502: Was formerly used to accommodate many superficially similar, but unrelated fungi. Rhizoctonia was introduced in 1815 by French mycologist Augustin Pyramus de Candolle for anamorphic plant pathogenic fungi that produce both hyphae and sclerotia . The name is derived from Ancient Greek, ῥίζα ( rhiza , "root") + κτόνος ( ktonos , "murder"), and de Candolle's original species, Rhizoctonia crocorum ( teleomorph Helicobasidium purpureum ),

9506-487: Was introduced by Belgian colonists to Rwanda to beautify their holdings. It then advanced by natural means to Lake Victoria, where it was first sighted in 1988. There, without any natural enemies, it has become an ecological plague, suffocating the lake, diminishing the fish reservoir, and hurting the local economies. It impedes access to Kisumu and other harbors. The water hyacinth has also appeared in Ethiopia , where it

9604-524: Was published in 1994 by Andersen & Stalpers. Only a few frequently used names are listed below. Many older names are of uncertain application or were never validly published, or both. Species are saprotrophic , often occurring in soil and producing basidiocarps (fruit bodies) on dead stems and plant detritus. They are also opportunistic plant pathogens, with an almost unlimited host range, and have been isolated from orchid mycorrhiza . Distribution appears to be cosmopolitan . Rhizoctonia solani causes

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