Editing Blight

{{Short description|Specific symptom affecting plants in response to infection by a pathogenic organism}}
{{about|plant diseases}}
{{Redirect|Bacterial blight|the barley blight|Bacterial blight (barley)}}
'''Blight''' is a specific [[symptom]] affecting [[plant]]s in response to infection by a [[pathogenic]] [[organism]].

==Description==
Blight is a rapid and complete [[chlorosis]], browning, then death of plant [[Tissue (biology)|tissue]]s such as leaves, branches, twigs, or floral organs.<ref>Agrios, George N. 2005. ''Plant Pathology''. 5th ed, Burlington, MA: Elsevier Academic Press.</ref>  Accordingly, many diseases that primarily exhibit this symptom are called blights. Several notable examples are:{{citation needed|date=August 2022}}
* [[Phytophthora infestans|Late blight of potato]], caused by the [[water mold]] ''[[Phytophthora infestans]]'' (Mont.) de Bary, the disease which led to the [[Great Irish Famine]]
* Southern corn leaf blight, caused by the [[fungus]] ''[[Cochliobolus heterostrophus]]'' (Drechs.) Drechs, [[anamorph]] ''[[Bipolaris maydis]]'' (Nisikado & Miyake) Shoemaker, incited a severe loss of corn in the United States in 1970.<ref>Partridge, J.E. "Southern Corn Leaf Blight." 2003. 8 August 2006. {{cite web|url=http://nu-distance.unl.edu/homer/disease/agron/corn/CoSCLB.html|title=Plant Pathology 369 - Southern Corn Leaf Blight Key words: Plant Disease, Bipolaris maydis, Helminthosporium maydis, Cochliobolus heterostrophus, Corn, Sorghum, Teosinte|access-date=2012-03-02|url-status=dead|archive-url=https://web.archive.org/web/20100723184952/http://nu-distance.unl.edu/homer/disease/agron/corn/CoSCLB.html|archive-date=2010-07-23}}</ref>
* [[Chestnut blight]], caused by the fungus ''Cryphonectria parasitica'' (Murrill) Barr, has nearly completely eradicated mature [[American chestnut]]s in North America.
* [[Citrus blight]], caused by an unknown agent, infects all citrus [[Grafting|scions]].
* [[Fire blight|Fire blight of pome fruits]], caused by the [[bacterium]] ''[[Erwinia amylovora]]'' (Burrill) Winslow et al., is the most severe disease of [[pear]] and also is found in [[apple]] and [[raspberry]], among others.
* Bacterial leaf blight of [[rice]], caused by the bacterium ''[[Xanthomonas oryzae]]'' (Uyeda & Ishiyama) Dowson.<ref>Oda, M., Sekizawa, Y., and Watanabe, T. 1966. "[[Phenazine]]s as Disinfectants Against Bacterial Leaf Blight of the Rice Plant." ''Applied Microbiology'' 14(3):365-367.</ref>
* Bacterial seedling blight of rice (''Oryza sativa''), caused by pathogen ''[[Burkholderia plantarii]]''<ref>{{cite journal|last1=Tanaka|first1=T.|last2=Katoh|first2=T.|last3=Satoh|first3=T.|title=Role of the rice seedlings [''Oryza sativa''] and Kouyawarabi (''Onoclea sensibilis L.'') infested with ''Burkholderia plantarii'' as the source of bacterial seedling blight of rice|journal=Annals of the Phytopathological Society of Japan|date=2002|volume=68|issue=3|pages=283–290|doi=10.3186/jjphytopath.68.283|url=https://www.jstage.jst.go.jp/article/jjphytopath1918/68/3/68_3_283/_article/-char/en|access-date=15 December 2021|language=ja|issn=0031-9473|doi-access=free }}</ref>
* Early blight of potato and tomato, caused by species of the ubiquitous fungal genus ''[[Alternaria]]''
* Leaf blight of the grasses e.g. ''[[Ascochyta]]'' species<ref>{{cite web|last1=Tisserat|first1=N.|title=Ascochyta Leaf Blight of Turf|url=https://extension.colostate.edu/topic-areas/yard-garden/ascochyta-leaf-blight-of-turf-2-901/|website=Colorado State University|access-date=11 September 2019}}</ref> and ''[[Alternaria triticina]]'' that causes blight in wheat<ref>{{cite web|title=Alternaria triticina (leaf blight of wheat)|url=https://www.cabi.org/isc/datasheet/4534|website=www.cabi.org|access-date=11 September 2019|language=en|date=27 September 2018}}</ref>
* [[Bur oak blight]], caused by the fungal pathogen ''Tubakia iowensis''.
* South American leaf blight, caused by the [[Ascomycota|ascomycete]] ''[[Pseudocercospora]] [[Pseudocercospora ulei|ulei]]'',<ref name="Guyot-Guen-2018">{{cite journal|last1=Guyot|first1=Jean|last2=Le Guen|first2=Vincent|title=A Review of a Century of Studies on South American Leaf Blight of the Rubber Tree|journal=[[Plant Disease (journal)|Plant Disease]]|publisher=[[American Phytopathological Society]]|volume=102|issue=6|year=2018|issn=0191-2917|doi=10.1094/pdis-04-17-0592-fe|pages=1052–1065|pmid=30673445|doi-access=free }}</ref><ref name="EPPO-GD">{{cite web|title=''Pseudocercospora ulei'' (MICCUL){{bracket|Overview}}|website=Global Database|publisher=EPPO ([[European and Mediterranean Plant Protection Organization]])|date=2002-04-09|url=http://gd.eppo.int/taxon/MICCUL|access-date=2021-08-28}}</ref><ref>[http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0104750#pone-0104750-g006 Erasing the Past: A New Identity for the Damoclean Pathogen Causing South American Leaf Blight of Rubber]</ref> also called ''Microcyclus ulei'',<ref>[http://www.plantwise.org/knowledgebank/datasheet.aspx?dsid=33893 South American Leaf Blight of rubber (''Microcyclus ulei'')], plantwise.org</ref> ended the cultivation of the rubber tree (''[[Hevea brasiliensis]]'') in South America.<ref name="Guyot-Guen-2018"/>

On leaf tissue, symptoms of blight are the initial appearance of lesions which rapidly engulf surrounding tissue. However, [[leaf spot]]s may, in advanced stages, expand to kill entire areas of leaf tissue and thus exhibit blight symptoms.

Blights are often named after their causative agent. For example, ''Colletotrichum'' blight is named after the fungus ''[[Colletotrichum capsici]]'', and ''Phytophthora'' blight is named after the water mold ''[[Phytophthora parasitica]]''.<ref>{{Cite web|author=Chase, A. R.|year=1984|title=Diseases of Foliage Plants - Revised List 1984|publisher=Agricultural Research Center - Apopka, University of Florida|url=http://ufdc.ufl.edu/UF00065331/00004|archive-url=https://web.archive.org/web/20141030060419/http://ufdc.ufl.edu/UF00065331/00004|archive-date=30 October 2014|url-status=live}}</ref>

When blights have been particularly vast and consequential in their effects, they have become named historical events, such as the 19th Century [[European Potato Failure|Potato Blight]], also known locally from its primary consequence as the ''Great famine'', the [[Great Famine (Ireland)|Great Famine of Ireland]], and [[Highland Potato Famine]], and the near extinction of the [[Juniperus bermudiana|Bermuda cedar]] during the 1940s and 1950s in the event described as ''The Blight'' or ''The Cedar Blight''.<ref>{{cite web|url=https://www.plantsnap.com/plantblog/types-of-cedar-trees/|title=13 Different Types of Cedar Trees (All Cedar Tree Varieties)|last=Undlin|first=Siri|date=2020-12-23|website=PlantSnap|publisher=PlantSnap Inc.|access-date=2021-10-05|quote=This tree-covered much of the island, but the forest was decimated first by settlers, and then later by an infestation of scale. It is an event known today as “the blight.” This caused a variety of pollinators to become extinct and is a harrowing example of how unchecked human development can cause a catastrophe in the natural world.}}</ref><ref>{{cite web|url=https://evolvingshores.weebly.com/speciation-at-spittal-pond.html|title=Speciation at Spittal Pond|author=<!--Not stated-->|date=<!--Not stated-->|website=Evolving Shores|publisher=Explorations in Biology, Bermuda College|access-date=2021-10-05|quote=in the 1940s, two species of scale were accidentally introduced, and, unable to deal with this foreign pest, 95% of Bermuda’s cedar trees were killed. The 5% of trees who survived the blight were found to be resistant to the scale. These have been propagated since then, and the Bermuda cedar survives today. Unfortunately the cedar was Bermuda’s main tree cover up until the blight, with little diversity to fill the void when the trees died off. Thus, some species who depended on and thrived in its branches, such as bluebirds and white-eyed vireo became critically endangered along with it. Others, such as the endemic cicada went extinct without it.}}</ref><ref>{{cite web|url=https://www.worldwildlife.org/ecoregions/na0301|title=Bermuda|last=Mastny|first=Lisa|date=|website=World Wildlife Fund|access-date=2021-10-05|quote=An estimated 95 percent of the surviving population of native Bermuda cedar (Juniperus bermudiana) was destroyed between 1946 and 1951 (Rueger and von Wallmenich 1996), following the accidental introduction of two coccoid scale insects (Sterrer 1998a). Only an estimated one percent of the original cedar forest survived the blight (BBP 1997).}}</ref><ref>{{cite web|url=https://www.frommers.com/destinations/bermuda/introduction/the-best-places-to-get-away-from-it-all|title=Bermuda: The Best Places to Get Away from It All in Bermuda|author=<!--Not stated-->|date=<!--Not stated-->|website=Frommer's|publisher=FrommerMedia LLC|access-date=2021-10-05|quote=Seymour's Pond Nature Reserve. Under the management of the Bermuda Audubon Society, this 1-hectare (2 1/2-acre) site attracts the occasional birder as well as romantic couples looking for a little privacy. Just past the pond, you'll spot pepper trees and old cedars that escaped the blight;}}</ref><ref>{{cite news|author=<!--Staff writer(s)/no by-line.-->|date=2011-02-10|title=Leader of fight against tree blight dies|url=https://www.royalgazette.com/international-business/article/20110210/leader-of-fight-against-tree-blight-dies|work=The Royal Gazette|location=Bermuda|access-date=2021-10-05|quote=Mr. Groves, who was made an Officer of the Order of the British Empire for his services to Bermuda and agriculture, was Assistant Director of Agriculture in the late 1940s when a blight decimated the Island's cedar forests.}}</ref><ref>{{cite news|last=Calnan|first=Patricia|date=2011-02-10|title=Learning about the cedar tree|url=https://www.royalgazette.com/other/lifestyle/article/20110210/learning-about-the-cedar-tree|work=The Royal Gazette|location=Bermuda|access-date=2021-10-05|quote=The accidental introduction of the Oyster-shell Scale and the Juniper Scale caused the demise of at least 85 percent of the cedar population by 1952, with more than 100,000 being felled during and after the scale infestation.}}</ref><ref>{{cite news|last=Hardy|first=Jessie Moniz|date=2020-10-14|title= Dark Bottom, a 1950s haven and horror|url=https://www.royalgazette.com/lifestyle/article/20201014/dark-bottom-a-1950s-haven-and-horror/|work=The Royal Gazette|location=Bermuda|access-date=2021-10-05|quote=Dark Bottom, a dense forest of cedar trees just below the lighthouse where he and his friends played. <br>“It was not scary by day, but at night if you had to cross that going somewhere you made time,” the 75-year-old said. “There was no stopping.”<br>He thinks the story was made up to ensure the neighbourhood children were home on time.<br>“We thought it was extraordinary that the beast had five fingers,” he said.<br>The trees were killed by the cedar blight in the late early 1950s}}</ref>

==Gallery==
<gallery>
File:Chestnut blight.jpg|Chestnut blight
File:Brown Felt Blight.jpg|Brown felt blight
File:Late blight on potato leaf 2.jpg|Potato late blight
File:Fire blight appletree fruit closeup.JPG|Fire blight appletree fruit
File:Three dead Bermuda cedars (Juniperus bermudiana) at Prospect Camp, Bermuda in 2019.jpg|Three dead [[Juniperus bermudiana|Bermuda cedars]] in 2019
</gallery>

==References==
{{Reflist}}

==External links==
{{Commons category|Blight}}
{{Wiktionary}}

*Berg A. 1926. Tomato Late Blight and its Relation to Late Blight of Potato.
*Bonn WG, Zwet TVD. Distribution and economic importance of fire blight. Fire blight: the disease and its causative agent, Erwinia amylovora.:37–53.
*Erskine JM. 1973. Characteristics of Erwinia amylovora bacteriophage and its possible role in the epidemiology of fire blight. Canadian Journal of Microbiology; 19(7):837–845.
*Johnson KB, Stockwell VO. 1998. MANAGEMENT OF FIRE BLIGHT: A Case Study in Microbial Ecology. Annual Review of Phytopathology 36:227–248.
*M. N. Schroth, S. V. Thomson, D. C. Hildebrand, W. J. Moller. 1974. Epidemiology and Control of Fire Blight. Annual Review of Phytopathology, 12:1, 389-412.
*Mcmanus PS. 1994. Role of Wind-Driven Rain, Aerosols, and Contaminated Budwood in Incidence and Spatial Pattern of Fire Blight in an Apple Nursery. Plant Disease 78:1059.
*Puławska J, Sobiczewski P. 2011. Phenotypic and genetic diversity of Erwinia amylovora: the causal agent of fire blight. Trees 26:3–12.
*Rico A, Ortiz-Barredo A, Ritter E, Murillo J. 2004. Genetic characterization of Erwinia amylovora strains by amplified fragment length polymorphism. Journal of Applied Microbiology; 96(2):302–310.
*Ritchie DF. 1977. Isolation of Erwinia amylovora Bacteriophage from Aerial Parts of Apple Trees. Phytopathology 77:101.
*Steiner PW. 1996. What We Don’t Know About Fire Blight. Acta Horticulture; (411):3–6.
*Thomas TM. 1992. Severity of Fire Blight on Apple Cultivars and Strains in Michigan. Plant Disease 76:1049.
*Vanneste JL. What is fire blight? Who is Erwinia amylovora? How to control it? Fire blight: the disease and its causative agent, Erwinia amylovora.:1–6.

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[[Category:Mycology]]
[[Category:Plant pathogens and diseases]]