''Phytophthora'' (from

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

(''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of plant-damaging

oomycete The Oomycetes (), or Oomycota, form a distinct phylogenetic lineage of fungus-like eukaryotic microorganisms within the Stramenopiles. They are filamentous and heterotrophic, and can reproduce both sexually and asexually. Sexual reproduction o ...

s (water molds), whose member species cause economic losses on crops worldwide, as well as

environmental damage Environment most often refers to: __NOTOC__ * Natural environment, referring respectively to all living and non-living things occurring naturally and the physical and biological factors along with their chemical interactions that affect an organism ...

in natural

ecosystem An ecosystem (or ecological system) is a system formed by Organism, organisms in interaction with their Biophysical environment, environment. The Biotic material, biotic and abiotic components are linked together through nutrient cycles and en ...

s. The cell wall of ''Phytophthora'' is made up of

cellulose Cellulose is an organic compound with the chemical formula, formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of glycosidic bond, β(1→4) linked glucose, D-glucose units. Cellulose is an important s ...

. The genus was first described by

Heinrich Anton de Bary Heinrich Anton de Bary (26 January 183119 January 1888) was a German surgeon, botanist, microbiologist, and mycologist (fungal systematics and physiology). He is considered a founding father of plant pathology (phytopathology) as well as the fou ...

in 1875. Approximately 210 species have been described, although 100–500 undiscovered ''Phytophthora'' species are estimated to exist.

Pathogenicity

''Phytophthora''

spp. A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of classification and a ...

are mostly pathogens of

dicotyledon The dicotyledons, also known as dicots (or, more rarely, dicotyls), are one of the two groups into which all the flowering plants (angiosperms) were formerly divided. The name refers to one of the typical characteristics of the group: namely, ...

s, and many are relatively host-specific parasites. '' P. cinnamomi'', though, infects thousands of species ranging from

club moss Lycopodiopsida is a class of vascular plants also known as lycopsids, lycopods, or lycophytes. Members of the class are also called clubmosses, firmosses, spikemosses and quillworts. They have dichotomously branching stems bearing simple leaves ...

es,

fern The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissue ...

cycad Cycads are seed plants that typically have a stout and woody (ligneous) trunk (botany), trunk with a crown (botany), crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants o ...

conifer Conifers () are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a sin ...

grass Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family (biology), family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos, the grasses of natural grassland and spe ...

es,

lilies ''Lilium'' ( ) is a genus of herbaceous flowering plants growing from bulbs, all with large and often prominent flowers. Lilies are a group of flowering plants which are important in culture and literature in much of the world. Most species are ...

, to members of many dicotyledonous families. Many species of ''Phytophthora'' are

plant Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they are predominantly Photosynthesis, photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with c ...

pathogen In biology, a pathogen (, "suffering", "passion" and , "producer of"), in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a Germ theory of d ...

s of considerable economic importance. '' P. infestans'' was the infective agent of the potato blight that caused the Great Famine of Ireland, and still remains the most destructive pathogen of

solanaceous Solanaceae (), commonly known as the nightshades, is a family of flowering plants in the order Solanales. It contains approximately 2,700 species, several of which are used as agricultural crops, medicinal plants, and ornamental plants. Many mem ...

crops, including tomato and potato.Ristaino, J. B., Cooke, D.E.L., Acuña, I., Muñoz, M. 2020. The Threat of Late Blight to Global Food Security. Pages 101-133 in: In Emerging Plant Disease and Global Food Security. A. Records and J. B. Ristaino, eds. American Phytopathological Society Press, St. Paul. https://doi.org/10.1094/9780890546383.006 The soya bean root and stem rot agent, '' P. sojae'', caused longstanding problems for the agricultural industry. In general, plant diseases caused by this genus are difficult to control chemically, thus the growth of resistant

cultivar A cultivar is a kind of Horticulture, cultivated plant that people have selected for desired phenotypic trait, traits and which retains those traits when Plant propagation, propagated. Methods used to propagate cultivars include division, root a ...

s is the main management strategy. Other important ''Phytophthora'' diseases are: * '' P. agathidicida''—causes collar-rot on

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

kauri (''

Agathis australis ''Agathis australis'', commonly known as kauri, is a species of coniferous tree in the family Araucariaceae, found north of 38°S in the northern regions of New Zealand's North Island. It is the largest (by volume) but not tallest species ...

''), New Zealand's most voluminous tree, an otherwise successful survivor of the

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. ...

* '' P. cactorum''—causes

rhododendron root rot ''Phytophthora cactorum'' is a fungal-like plant pathogen belonging to the Oomycota phylum. It is the causal agent of root rot on rhododendron and many other species, as well as leather rot of strawberries. . Hosts, symptoms, and diagnosis ''Ph ...

affecting rhododendrons, azaleas, and

orchids Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Orchids are cosmopolitan plants that are found in almost every habitat on Earth ...

, and causes bleeding canker in hardwood trees * '' P. capsici''—infects

Cucurbitaceae The Cucurbitaceae (), also called cucurbits or the gourd family, are a plant family (biology), family consisting of about 965 species in 101 genera.

fruits, such as

cucumber The cucumber (''Cucumis sativus'') is a widely-cultivated creeping vine plant in the family Cucurbitaceae that bears cylindrical to spherical fruits, which are used as culinary vegetables.squash Squash most often refers to: * Squash (sport), the high-speed racquet sport also known as squash racquets * Squash (plant), the fruit of vines of the genus ''Cucurbita'' Squash may also refer to: Sports * Squash (professional wrestling), an extr ...

* '' P. cinnamomi''—causes cinnamon root rot affecting forest and fruit trees, and woody ornamentals including

arborvitae ''Thuja'' ( ) is a genus of coniferous tree or shrub in the Cupressaceae (cypress family). There are five species in the genus, two native to North America and three native to eastern Asia. The genus is monophyletic and sister to ''Thujopsis''. M ...

azalea Azaleas ( ) are flowering shrubs in the genus ''Rhododendron'', particularly the former sections ''Rhododendron sect. Tsutsusi, Tsutsusi'' (evergreen) and ''Pentanthera'' (deciduous). Azaleas bloom in the spring (April and May in the temperate ...

Chamaecyparis ''Chamaecyparis'', common names cypress or false cypress (to distinguish it from related cypresses), is a genus of conifers in the cypress family Cupressaceae, native to eastern Asia (Japan and Taiwan) and to the western and eastern margins o ...

dogwood ''Cornus'' is a genus of about 30–60 species of woody plants in the family Cornaceae, commonly known as dogwoods or cornels, which can generally be distinguished by their blossoms, berries, and distinctive bark. Most are deciduous ...

forsythia ''Forsythia'' , is a genus of flowering plants in the olive family Oleaceae. There are about 11 species, mostly native to Eastern Asia, but one native to Southeastern Europe. ''Forsythia'' – also one of the plant's common names – is named ...

Fraser fir The Fraser fir (''Abies fraseri''), sometimes spelled Frasier fir, is an endangered species of fir native to the Appalachian Mountains of the southeastern United States. They are endemic to only seven montane regions in the Appalachian Mountains ...

, hemlock, Japanese holly,

juniper Junipers are coniferous trees and shrubs in the genus ''Juniperus'' ( ) of the cypress family Cupressaceae. Depending on the taxonomy, between 50 and 67 species of junipers are widely distributed throughout the Northern Hemisphere as far south ...

, Pieris,

rhododendron ''Rhododendron'' (; : ''rhododendra'') is a very large genus of about 1,024 species of woody plants in the Ericaceae, heath family (Ericaceae). They can be either evergreen or deciduous. Most species are native to eastern Asia and the Himalayan ...

Taxus ''Taxus'' is a genus of coniferous trees or shrubs known as yews in the family Taxaceae. Yews occur around the globe in temperate zones of the northern hemisphere, northernmost in Norway and southernmost in the South Celebes. Some populations ex ...

white pine ''Pinus'', the pines, is a genus of approximately 111 extant tree and shrub species. The genus is currently split into two subgenera: subgenus ''Pinus'' (hard pines), and subgenus ''Strobus'' (soft pines). Each of the subgenera have been further ...

American chestnut The American chestnut (''Castanea dentata'') is a large, fast-growing deciduous tree of the Fagaceae, beech family native to eastern North America. As is true of all species in the genus ''Chestnut, Castanea'', the American chestnut produces Bur ...

and Australian woody plants, especially

eucalypt Eucalypt is any woody plant with Capsule (fruit), capsule fruiting bodies belonging to one of seven closely related genera (of the tribe Eucalypteae) found across Australia: ''Eucalyptus'', ''Corymbia'', ''Angophora'', ''Stockwellia'', ''Allosyn ...

and

banksia ''Banksia'' is a genus of around 170 species of flowering plants in the family Proteaceae. These Australian wildflowers and popular garden plants are easily recognised by their characteristic flower spikes, and woody fruiting "cones" and head ...

. * '' P. citricola''—causes root rot and stem cankers in citrus trees * '' P. fragariae''—causes red root rot affecting strawberries * '' P. infestans'' causes the serious disease known as potato (late) blight: responsible for the Great Famine of Ireland. * '' P. kernoviae''—pathogen of

beech Beech (genus ''Fagus'') is a genus of deciduous trees in the family Fagaceae, native to subtropical (accessory forest element) and temperate (as dominant element of Mesophyte, mesophytic forests) Eurasia and North America. There are 14 accepted ...

and rhododendron, also occurring on other trees and shrubs including

oak An oak is a hardwood tree or shrub in the genus ''Quercus'' of the beech family. They have spirally arranged leaves, often with lobed edges, and a nut called an acorn, borne within a cup. The genus is widely distributed in the Northern Hemisp ...

, and holm oak. First seen in Cornwall, UK, in 2003. * '' P. lateralis''—causes cedar root disease in

Port Orford cedar ''Chamaecyparis lawsoniana'', known as Port Orford cedar or Lawson's cypress, is a species of conifer in the genus ''Chamaecyparis'', family Cupressaceae. It is native to Oregon and northwestern California, and grows from sea level up to in the ...

trees * '' P. megakarya''—one of the cocoa

black pod disease Black pod disease is a fungal disease of Cocoa trees. It is mostly found in tropical areas where cocoa trees grow, and its spores are spread via the heavy rainfalls that can occur in tropical climates. Annually, the pathogen can cause a yield loss ...

species, is invasive and probably responsible for the greatest

cocoa Cocoa may refer to: Chocolate * Chocolate * ''Theobroma cacao'', the cocoa tree * Cocoa bean, seed of ''Theobroma cacao'' * Chocolate liquor, or cocoa liquor, pure, liquid chocolate extracted from the cocoa bean, including both cocoa butter and ...

crop loss in Africa * '' P. multivora''—discovered in analysis of isolates with ''P. cinnamomi'' dieback infections of

tuart forest Tuart forest is an open forest in which the dominant overstorey tree is ''Eucalyptus gomphocephala'' (tuart). This form of vegetation occurs only in the Southwest Botanical Province of Western Australia. Tuart being predominantly a coastal tree, ...

s of Southwest Australia, which were previously diagnosed as ''P. citricola''. The species was found occurring on many other taxa, so named ''multivora''. * '' P. nicotianae''—infects

tobacco Tobacco is the common name of several plants in the genus '' Nicotiana'' of the family Solanaceae, and the general term for any product prepared from the cured leaves of these plants. More than 70 species of tobacco are known, but the ...

and

onion An onion (''Allium cepa'' , from Latin ), also known as the bulb onion or common onion, is a vegetable that is the most widely cultivated species of the genus '' Allium''. The shallot is a botanical variety of the onion which was classifie ...

s * '' P. palmivora''—causes fruit rot in

coconut The coconut tree (''Cocos nucifera'') is a member of the palm tree family (biology), family (Arecaceae) and the only living species of the genus ''Cocos''. The term "coconut" (or the archaic "cocoanut") can refer to the whole coconut palm, ...

s and

betel nut The areca nut ( or ) or betel nut () is the fruit of the areca palm ('' Areca catechu''). The palm is originally native to the Philippines, but was carried widely through the tropics by the Austronesian migrations and trade since at least 1 ...

s * '' P. ramorum''—infects over 60 plant genera and over 100 host species; causes

sudden oak death James Green aka "Sudden" is a fictional character created by an English author Oliver Strange in the early 1930s as the hero of a series, originally published by George Newnes Books Ltd, set in the American Wild West era. Oliver Strange died ...

* '' P. quercina''—causes oak death * '' P. sojae''—causes

soybean The soybean, soy bean, or soya bean (''Glycine max'') is a species of legume native to East Asia, widely grown for its edible bean. Soy is a staple crop, the world's most grown legume, and an important animal feed. Soy is a key source o ...

root rot Research beginning in the 1990s placed some of the responsibility for European forest die-back on the activity of imported Asian ''Phytophthoras''. In 2019, scientists in Connecticut were conducting experiments testing various methods to grow healthier Fraser trees when they accidentally discovered a new species of ''Phytophthora'', which they called ''P. abietivora''. The fact that these scientists so readily discovered a new species further suggests that there could be many more species waiting to be discovered.

Reproduction

''Phytophthora'' species may reproduce sexually or asexually. In many species, sexual structures have never been observed, or have only been observed in laboratory matings. In

homothallic In fungi and algae, homothallism refers to the condition in which a single individual or thallus carries the genetic determinants (i.e., both mating types or sexes) required to undergo sexual reproduction without the need for a distinct mating partn ...

species, sexual structures occur in single culture.

Heterothallic Heterothallic species have sexes that reside in different individuals. The term is applied particularly to distinguish heterothallic fungi, which require two compatible partners to produce sexual spores, from homothallic ones, which are capable ...

species have mating strains, designated as A1 and A2. When mated,

antheridia An antheridium is a haploid structure or organ producing and containing male gametes (called ''antherozoids'' or sperm). The plural form is antheridia, and a structure containing one or more antheridia is called an androecium. The androecium is al ...

introduce gametes into

oogonia An oogonium (: oogonia) is a small diploid cell which, upon maturation, forms a primordial follicle in a female fetus or the female (haploid or diploid) gametangium of certain thallophytes. In the mammalian fetus Oogonia are formed in lar ...

, either by the oogonium passing through the antheridium (amphigyny) or by the antheridium attaching to the proximal (lower) half of the oogonium (paragyny), and the union producing oospores. Like animals, but not like most true fungi, meiosis is gametic, and somatic nuclei are diploid. Asexual (mitotic) spore types are

chlamydospore A chlamydospore is the thick-walled large resting spore of several kinds of fungi, including Ascomycota such as '' Candida'', Basidiomycota such as '' Panus'', and various Mortierellales species. It is the life-stage which survives in unfavourab ...

s, and

sporangia A sporangium (from Late Latin, ; : sporangia) is an enclosure in which spores are formed. It can be composed of a unicellular organism, single cell or can be multicellular organism, multicellular. Virtually all plants, fungus, fungi, and many ot ...

which produce

zoospore A zoospore is a motile asexual spore that uses a flagellum for locomotion in aqueous or moist environments. Also called a swarm spore, these spores are created by some protists, bacteria, and fungi to propagate themselves. Certain zoospores are ...

s. Chlamydospores are usually spherical and pigmented, and may have a thickened cell wall to aid in their role as a survival structure. Sporangia may be retained by the subtending hyphae (noncaducous) or be shed readily by wind or water tension (caducous) acting as dispersal structures. Also, sporangia may release zoospores, which have two unlike

flagella A flagellum (; : flagella) (Latin for 'whip' or 'scourge') is a hair-like appendage that protrudes from certain plant and animal sperm cells, from fungal spores ( zoospores), and from a wide range of microorganisms to provide motility. Many pr ...

which they use to swim towards a host plant. Zoospores (and zoospores of ''

Pythium ''Pythium'' is a genus of parasitic oomycetes. They were formerly classified as fungi. Most species are plant parasites, but '' Pythium insidiosum'' is an important pathogen of animals, causing pythiosis. The feet of the fungus gnat are fre ...

'', also in the Peronosporales) recognize not only hosts but particular locations on hosts. ''Phytophthora'' zoospores recognize and attach to specific root surface regions. This is a high degree of specificity at an early stage of cell development.

Evolution and resemblance to fungi

''Phytophthora'' is sometimes referred to as a

fungus A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one ...

-like organism, but it is classified under a different

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

altogether:

SAR supergroup SAR is a highly diverse clade of eukaryotes, often considered a supergroup, that includes stramenopiles (heterokonts), alveolates, and rhizarians. It is a node-based taxon (under the Sar name), including all descendants of the three groups' ...

(Harosa) (also under

Stramenopila The stramenopiles, also called heterokonts, are protists distinguished by the presence of stiff tripartite external hairs. In most species, the hairs are attached to flagella, in some they are attached to other areas of the cellular surface, and ...

and previously under

Chromista Chromista is a proposed but polyphyletic obsolete Biology, biological Kingdom (biology), kingdom, refined from the Chromalveolata, consisting of single-celled and multicellular eukaryotic species that share similar features in their Photosynthesi ...

). This is a good example of

convergent evolution Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last comm ...

: ''Phytophthora'' is morphologically very similar to true fungi yet its evolutionary history is completely distinct. In contrast to fungi, SAR supergroup is more closely related to plants than to animals. Whereas fungal cell walls are made primarily of

chitin Chitin (carbon, C8hydrogen, H13oxygen, O5nitrogen, N)n ( ) is a long-chain polymer of N-Acetylglucosamine, ''N''-acetylglucosamine, an amide derivative of glucose. Chitin is the second most abundant polysaccharide in nature (behind only cell ...

, ''Phytophthora'' cell walls are constructed mostly of

Ploidy Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Here ''sets of chromosomes'' refers to the number of maternal and paternal chromosome copies, ...

levels are different between these two groups; ''Phytophthora'' species have

diploid Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Here ''sets of chromosomes'' refers to the number of maternal and paternal chromosome copies, ...

(paired) chromosomes in the vegetative (growing, nonreproductive) stage of life, whereas fungi are almost always

haploid Ploidy () is the number of complete sets of chromosomes in a cell (biology), cell, and hence the number of possible alleles for Autosome, autosomal and Pseudoautosomal region, pseudoautosomal genes. Here ''sets of chromosomes'' refers to the num ...

in this stage. Biochemical pathways also differ, notably the highly conserved

lysine Lysine (symbol Lys or K) is an α-amino acid that is a precursor to many proteins. Lysine contains an α-amino group (which is in the protonated form when the lysine is dissolved in water at physiological pH), an α-carboxylic acid group ( ...

synthesis path..

Species

The NCBI lists: *'' Phytophthora acerina'' *''

Phytophthora afrocarpa ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *''

Phytophthora agathidicida ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental da ...

'' * ''

Phytophthora aleatoria ''Phytophthora'' (from Greek language, Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as e ...

'' *'' Phytophthora alni'' *''

Phytophthora × alni ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' * '' Phytophthora alpina'' *'' Phytophthora alticola'' *'' Phytophthora amaranthi'' *'' Phytophthora amnicola'' *''

Phytophthora amnicola × moyootj ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora xandina'' *'' Phytophthora aquimorbida'' *'' Phytophthora arecae'' *'' Phytophthora arenaria'' *''

Phytophthora cf. arenaria ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora aff. arenaria'' *'' Phytophthora asiatica'' *'' Phytophthora asparagi'' *'' Phytophthora aff. asparagi'' *'' Phytophthora attenuata'' *'' Phytophthora austrocedrae'' *'' Phytophthora balyanboodja'' *''Phytophthora batemanensis'' syn. '' Halophytophthora batemanensis'' Phytophthora betacei *'' Phytophthora bilorbang'' *'' Phytophthora bishii'' *'' Phytophthora boehmeriae'' *'' Phytophthora boodjera'' *'' Phytophthora borealis'' *'' Phytophthora botryosa'' *'' Phytophthora cf. botryosa'' *'' Phytophthora aff. botryosa'' *'' Phytophthora brassicae'' *''

Phytophthora cactorum ''Phytophthora cactorum'' is a fungal-like plant pathogen belonging to the Oomycota phylum. It is the causal agent of root rot on rhododendron and many other species, as well as leather rot of strawberries. . Hosts, symptoms, and diagnosis ''Phy ...

'' **'' Phytophthora cactorum var. applanata'' *''

Phytophthora cactorum × hedraiandra ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora cajani'' *'' Phytophthora × cambivora'' *'' Phytophthora capensis'' *''

Phytophthora capsici ''Phytophthora capsici'' is an oomycete plant pathogen that causes blight and fruit rot of peppers and other important commercial crops. It was first described by L. Leonian at the New Mexico State University Agricultural Experiment Station in ...

'' *''

Phytophthora aff. capsici ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *''

Phytophthora captiosa ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora castaneae'' *'' Phytophthora castanetorum'' *''

Phytophthora chesapeakensis ''Phytophthora'' (from Greek language, Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as e ...

'' *'' Phytophthora chlamydospora'' *'' Phytophthora chrysanthemi'' *'' Phytophthora cichorii'' *'' Phytophthora aff. cichorii'' *''

Phytophthora cinnamomi ''Phytophthora cinnamomi'', also known as cinnamon fungus, is a soil-borne water mould that produces an infection which causes a condition in plants variously called "dieback", "root rot", or (in certain '' Castanea'' species), "ink disease". O ...

'' **'' Phytophthora cinnamomi var. cinnamomi'' **'' Phytophthora cinnamomi var. parvispora'' **'' Phytophthora cinnamomi var. robiniae'' *''

Phytophthora citricola ''Phytophthora citricola'' is a plant pathogen. It was first described by Kaneyoshi (Kenkichi) Sawada in 1927 when it was isolated from orange trees in present-day Taiwan Taiwan, officially the Republic of China (ROC), is a country in E ...

'' *'' Phytophthora aff. citricola'' *''

Phytophthora citrophthora ''Phytophthora citrophthora'', also known as brown rot of citrus, is a soil borne oomycete that infects several economically important citrus crops. A diagnostic symptom of ''P. citrophthora'' is gummosis, wherein lesions around the base of the t ...

'' **'' Phytophthora citrophthora var. clementina'' *'' Phytophthora aff. citrophthora'' *'' Phytophthora clandestina'' *'' Phytophthora cocois'' *'' Phytophthora colocasiae'' *'' Phytophthora condilina'' *'' Phytophthora constricta'' *'' Phytophthora cooljarloo'' *'' Phytophthora crassamura'' *''

Phytophthora cryptogea ''Phytophthora cryptogea'' is a species of water mould in the family Pythiaceae. It is a plant pathogen that infects several species of cultivated plants, including over 40 species of cultivated flowers.Olson, H. A., et al. (2011)Phylogenetic hi ...

'' *'' Phytophthora aff. cryptogea'' *'' Phytophthora cuyabensis'' *'' Phytophthora cyperi'' *'' Phytophthora dauci'' *'' Phytophthora aff. dauci'' *''

Phytophthora drechsleri ''Phytophthora drechsleri'' is a plant pathogen with many hosts. Affected plants See: * List of potato diseases * List of maize diseases * List of almond diseases * List of apricot diseases * List of beet diseases * List of caneberries diseas ...

'' **'' Phytophthora drechsleri var. cajani'' *''

Phytophthora elongata ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora cf. elongata'' *'' Phytophthora erythroseptica'' **'' Phytophthora erythroseptica var. pisi'' *'' Phytophthora aff. erythroseptica'' *'' Phytophthora estuarina'' *''

Phytophthora europaea ''Phytophthora europaea'' is a non-papillate homothallic plant pathogen that mainly infects European oak. It differs from other species of the genus (like '' P. fragariae'') by producing oogonia with tapered bases, irregular walls and exclusively ...

'' *'' Phytophthora fallax'' *'' Phytophthora flexuosa'' *'' Phytophthora fluvialis'' *''

Phytophthora fluvialis × moyootj ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora foliorum'' *'' Phytophthora formosa'' *'' Phytophthora formosana'' *''

Phytophthora fragariae ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

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Phytophthora fragariaefolia ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora frigida'' *'' Phytophthora gallica'' *'' Phytophthora gemini'' *'' Phytophthora gibbosa'' *'' Phytophthora glovera'' *'' Phytophthora gonapodyides'' *'' Phytophthora gondwanensis'' *'' Phytophthora gregata'' *'' Phytophthora cf. gregata'' *'' Phytophthora hedraiandra'' *'' Phytophthora aff. hedraiandra'' *''

Phytophthora × heterohybrida ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora heveae'' *''

Phytophthora hibernalis ''Phytophthora hibernalis'' is a plant pathogen infecting citrus ''Citrus'' is a genus of flowering trees and shrubs in the family Rutaceae. Plants in the genus produce citrus fruits, including important crops such as oranges, mandarin ...

'' *'' Phytophthora himalayensis'' *'' Phytophthora himalsilva'' *'' Phytophthora aff. himalsilva'' *'' Phytophthora humicola'' *'' Phytophthora aff. humicola'' *'' Phytophthora hydrogena'' *'' Phytophthora hydropathica'' Hong, C. & Gallegly, M. 2010 *'' Phytophthora idaei'' *'' Phytophthora ilicis'' *''

Phytophthora × incrassata ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

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Phytophthora infestans ''Phytophthora infestans'' is an oomycete or Oomycete, water mold, a fungus-like microorganism that causes the serious potato and tomato disease known as late blight or potato blight. Early blight, caused by ''Alternaria solani'', is also often c ...

'' *'' Phytophthora aff. infestans'' *'' Phytophthora inflata'' *''

Phytophthora insolita ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora cf. insolita'' *'' Phytophthora intercalaris'' *'' Phytophthora intricata'' *'' Phytophthora inundata'' *'' Phytophthora ipomoeae'' *'' Phytophthora iranica'' *'' Phytophthora irrigata'' *''

Phytophthora katsurae ''Phytophthora katsurae'' (better-known as ''P. castaneae'') is a plant pathogen. It was first isolated from chestnut (''Castanea'') trees in Japan.http://www.extento.hawaii.edu/Kbase/crop/Type/p_katsu.htm ''Phytophthora katsurae''. ''Crop Knowl ...

'' *'' Phytophthora kelmania'' *''

Phytophthora kernoviae ''Phytophthora kernoviae'' is a plant pathogen that mainly infects European beech (''Fagus sylvatica'') and ''Rhododendron ponticum''. It was first identified in 2003 in Cornwall, UK when scientists were surveying for the presence of ''Phytopht ...

'' *'' Phytophthora kwongonina'' *'' Phytophthora lactucae'' *'' Phytophthora lacustris'' *'' Phytophthora lacustris × riparia'' *''

Phytophthora lateralis ''Phytophthora lateralis'' is a soil-borne plant pathogen that causes cedar root disease in Port Orford cedars ('' Chamaecyparis lawsoniana''). This pathogen was first noted to cause disease in around 1920 on nursery stock near Seattle.Tucker, C ...

'' *'' Phytophthora lilii'' *'' Phytophthora litchii'' *'' Phytophthora litoralis'' *''

Phytophthora litoralis × moyootj ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

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Phytophthora macilentosa ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora macrochlamydospora'' *'' Phytophthora meadii'' *'' Phytophthora aff. meadii'' *'' Phytophthora medicaginis'' *''

Phytophthora medicaginis × cryptogea ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

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Phytophthora mediterranea ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

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Phytophthora megakarya ''Phytophthora megakarya'' is an oomycete plant pathogen that causes black pod disease in cocoa trees in west and central Africa. This pathogen can cause detrimental loss of yield in the economically important cocoa industry, worth approximate ...

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Phytophthora megasperma ''Phytophthora megasperma'' is a species of water mould in the family Peronosporaceae. It is well known as a plant pathogen with many hosts. It often causes a plant disease called root rot.Phytophthora melonis'' *'' Phytophthora mengei'' *'' Phytophthora mexicana'' *'' Phytophthora cf. mexicana'' *'' Phytophthora mirabilis'' *'' Phytophthora mississippiae'' *'' Phytophthora morindae'' *'' Phytophthora moyootj'' *'' Phytophthora moyootj × fluvialis'' *''

Phytophthora moyootj × litoralis ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

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Phytophthora moyootj × thermophila ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

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Phytophthora × multiformis ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora multivesiculata'' *''

Phytophthora multivora ''Phytophthora multivora'' is a species of Oomycete, water moulds, identified as a plant pathogen implicated in dieback. It was first isolated in tuart forest of Southwest Australia in a study of the decline of tuart ''Eucalyptus gomphocephala'' ...

'' *'' Phytophthora nagaii'' *'' Phytophthora nemorosa'' *''

Phytophthora nicotianae ''Phytophthora nicotianae'' or black shank is an oomycete belonging to the order Peronosporales and family Peronosporaceae. Hosts and symptoms ''Phytophthora nicotianae'' has a broad host range comprising 255 genera from 90 families. Hosts inclu ...

'' ** ''Phytophthora nicotianae'' var. ''parasitica'' * ''Phytophthora nicotianae'' × ''cactorum'' *'' Phytophthora niederhauserii'' * ''Phytophthora'' cf. ''niederhauserii'' *''

Phytophthora obscura ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora occultans'' *'' Phytophthora oleae'' *'' Phytophthora ornamentata'' *'' Phytophthora pachypleura'' *''

Phytophthora palmivora ''Phytophthora palmivora'' is an oomycete that causes bud-rot of Arecaceae, palms, fruit-rot or kole-roga of coconut and areca nut. These are among the most serious diseases caused by fungi and Mold (fungus), moulds in South India. Outbreaks occu ...

'' ** ''Phytophthora palmivora'' var. ''palmivora'' *''

Phytophthora parasitica ''Phytophthora nicotianae'' or black shank is an oomycete belonging to the order Peronosporales and family Peronosporaceae. Hosts and symptoms ''Phytophthora nicotianae'' has a broad host range comprising 255 genera from 90 Family (biology), fam ...

'' **'' Phytophthora parasitica var. nicotianae'' **''

Phytophthora parasitica var. piperina ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora parsiana'' *'' Phytophthora aff. parsiana'' *'' Phytophthora parvispora'' *''

Phytophthora × pelgrandis ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

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Phytophthora phaseoli ''Phytophthora phaseoli'' is a plant pathogen which infects lima bean A lima bean (''Phaseolus lunatus''), also commonly known as butter bean, sieva bean, double bean or Madagascar bean, is a legume grown for its edible seeds or beans. Origi ...

'' *'' Phytophthora pini'' *'' Phytophthora pinifolia'' *'' Phytophthora pisi'' *'' Phytophthora pistaciae'' *'' Phytophthora plurivora'' *''

Phytophthora pluvialis ''Phytophthora pluvialis'' is a semi-papillate plant pathogen that mainly infects Notholithocarpus, tanoak-Douglas-fir forests of western Oregon. It was reported in Cornwall. UK, in October 2021; the first record for Europe. Description ''Phytoph ...

'' *'' Phytophthora polonica'' *''

Phytophthora porri ''Phytophthora'' (from Greek language, Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as e ...

'' *'' Phytophthora primulae'' *'' Phytophthora aff. primulae'' *'' Phytophthora pseudocryptogea'' *'' Phytophthora pseudolactucae'' *'' Phytophthora pseudorosacearum'' *'' Phytophthora pseudosyringae'' *'' Phytophthora pseudotsugae'' *'' Phytophthora aff. pseudotsugae'' *'' Phytophthora psychrophila'' *'' Phytophthora quercetorum'' *'' Phytophthora quercina'' *'' Phytophthora quininea'' *''

Phytophthora ramorum ''Phytophthora ramorum'' is the oomycete known to cause the disease sudden oak death (SOD). The disease kills oak and other species of trees and has had devastating effects on the oak populations in California and Oregon, as well as being present ...

'' Werres, De Cock & Man in’t Veld 2001 *'' Phytophthora rhizophorae'' *'' Phytophthora richardiae'' *''

Phytophthora riparia ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora rosacearum'' *'' Phytophthora aff. rosacearum'' *''

Phytophthora rubi ''Phytophthora rubi'' is the principal cause of root rot in red raspberry. Originally classified as a variant of '' P. fragariae'' some now consider it a distinct species. This organism has been isolated from raspberries in Europe, North America, ...

'' *'' Phytophthora sansomea'' *'' Phytophthora sansomeana'' *'' Phytophthora aff. sansomeana'' *''

Phytophthora × serendipita ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora sinensis'' *''

Phytophthora siskiyouensis ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

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Phytophthora sojae ''Phytophthora sojae'' is an oomycete and a soil-borne plant pathogen that causes stem and root rot of soybean. This is a prevalent disease in most soybean growing regions, and a major cause of crop loss. In wet conditions the pathogen produces ...

'' *'' Phytophthora stricta'' *'' Phytophthora sulawesiensis'' *'' Phytophthora syringae'' *'' Phytophthora tabaci'' *''

Phytophthora tentaculata ''Phytophthora tentaculata'' is a plant pathogen that causes root and stalk rot. It was first isolated in 1993 in a nursery in Germany infecting ''Chrysanthemum'', ''Verbena'', and ''Delphinium ajacis''. It has since been found infecting a ''Ver ...

'' *'' Phytophthora terminalis'' *'' Phytophthora thermophila'' *'' Phytophthora thermophila × amnicola'' *''

Phytophthora thermophila × moyootj ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'' *'' Phytophthora tonkinensis'' *'' Phytophthora trifolii'' *'' Phytophthora tropicalis'' *'' Phytophthora cf. tropicalis'' *'' Phytophthora tubulina'' *'' Phytophthora tyrrhenica'' *''

Phytophthora uliginosa ''Phytophthora uliginosa'' is a non-papillate homothallic plant pathogen that mainly infects European oak. It differs from other species of the genus (like '' P. fragariae'') by its large oogonia with exclusively paragynous antheridia and the ...

'' *'' Phytophthora undulata'' *'' Phytophthora uniformis'' *'' Phytophthora vignae'' **'' Phytophthora vignae f. sp. adzukicola'' *'' Phytophthora virginiana'' *'' Phytophthora vulcanica''

''References''

Coomber, A., Saville, A., Carbone, I. and Ristaino, J. 2023. An open T base phylogeny for emerging ''Phytophthora'' species. PLOS ONE: https://doi.org/10.1371/journal.pone.0283540

External links

* ecticut

"''Phytophthora'' Canker – Identification, Biology and Management"
Bartlett TreeExperts Online Resource Library
"''Phytophthora'' Root Rot – Identification, Biology andManagement"
Bartlett Tree Experts Online Resource Library
Dieback Working Group
– Western Australia {{Authority control Phytophthora"> Water mould plant pathogens and diseases Oomycete genera">Water mould plant pathogens and diseases">Phytophthora"> Water mould plant pathogens and diseases Oomycete genera

Pathogenicity

Reproduction

Evolution and resemblance to fungi

Species

''References''

Further reading

External links