Phytophthora gemini


   Phytophthora  spp. in subclade 6a:  portion of the seven-loci ML phylogeny featuring the type cultures of 212 described species (by T. Bourret). Notice the position of   P. gemini  Ex-type CBS 123381 = Samp;T BL 97 . Gloria Abad, USDA Samp;T.
Phytophthora spp. in subclade 6a: portion of the seven-loci ML phylogeny featuring the type cultures of 212 described species (by T. Bourret). Notice the position of P. gemini Ex-type CBS 123381 = S&T BL 97. Gloria Abad, USDA S&T.
   Phytophthora  spp. in subclade 6a:  Morphological Tabular key (PDF) and Tabular key legends (PDF) in IDphy2 KEY SECTION. Notice the data of   P. gemini  Ex-type CBS 123381 = Samp;T BL 97 . Gloria Abad, USDA Samp;T.
Phytophthora spp. in subclade 6a: Morphological Tabular key (PDF) and Tabular key legends (PDF) in IDphy2 KEY SECTION. Notice the data of P. gemini Ex-type CBS 123381 = S&T BL 97. Gloria Abad, USDA S&T.

Name and publication

Phytophthora gemini Man in 't Veld, K. Rosend., Brouwer & De Cock (2011)

Man in ’t Veld WA, Rosendahl KC, Brouwer H, and de Cock AW. 2011. Phytophthora gemini sp. nov., a new species isolated from the halophilic plant Zostera marina in the Netherlands. Fungal Biol. 115: 724–732.

Corresponding author: w.a.man.in.t.veld@minlnv.nl

Nomenclature

from Man in ’t Veld et al. (2011)

Mycobank

MB519967

Etymology

geminus is twin, refering to two sporangiasporangia:
sac within which zoospores form, especially when water is cooled to about 10°C below ambient temperature; in solid substrates, sporangia usually germinate by germ tubes
on one hypha

Typification

Type: THE NETHERLANDS, Lake Grevelingen, from Zostera marina, CBS 123381, dried culture, in CBS-KNAW, Fungal Biodiversity Centre, Utrecht, the Netherlands

Ex-type: CBS 123381

Sequences for ex-type in original manuscript: CBS 123381 = ITS rDNA FJ217680

Ex-type in other collections

(ET) CBS 123381, WPC P15880, WMihV-2008, S&T BL 97 (Abad)

Molecular identification

Voucher sequences for barcoding genes (ITS rDNA and COI) of the ex-type (see Molecular protocols page)

Phytophthora gemini isolate P15880 = ITS rDNA HQ261693, COI HQ261440

Voucher sequences for Molecular Toolbox with seven genes (ITS, β-tub, COI, EF1α, HSP90, L10, and YPT1

(see Molecular protocols page) (In Progress)

Voucher sequences for Metabarcoding High-throughput Sequencing (HTS) Technologies [Molecular Operational Taxonomic Unit (MOTU)]

(see Molecular protocols page) (In Progress)

Sequences with multiple genes for ex-type in other sources
Position in multigenic phylogeny with 7 genes (ITS, β-tub, COI, EF1α, HSP90, L10, and YPT1)

Clade clade:
a taxonomic group of organisms classified together on the basis of homologous features traced to a common ancestor
6a

Morphological identification

adapted from Man in ’t Veld et al. (2011)

Colonies and cardinal temperatures

Colony colony:
assemblage of hyphae which usually develops form a single source and grows in a coordinated way
morphology after 7 days on PDA, V-8, MEA with fine chrysanthemum pattern. Minimum growth temperature 5°C, optimum 24–27°C, and maximum 33°C.

Conditions for growth and sporulation

Sporangia formed abundantly in sterile filtered pond water.

Asexual phase

Sporangia nonpapillate; persistentpersistent:
pertaining to sporangia that remain attached to the sporangiophore and do not separate or detach easily (cf. caducous)
; obovoidobovoid:
inversely egg-shaped; ovoid, but with the widest part at the apex
, ellipsoidellipsoid:
refers to a solid body that forms an ellipse in the longitudinal plane and a circle in cross section; many fungal spores are ellipsoidal or elliptic
, ovoidovoid:
egg-shaped, with the widest part at the base of the sporangium and the narrow part at the apex
, and obpyriformobpyriform:
inversely pear-shaped, i.e. with the widest part at the point of attachment (cf. pyriform)
, often with a tapered basetapered base:
pertaining to the base of a sporangium or oogonium; funnel-shaped
(53–31 µm) showing a conspicuous basal plugbasal plug:
a plug protruding into a sporangium from the basal cross wall, separating it from the sporangiophore
, and originated in unbranched and simple sympodial sporangiophores. Secondary sporangiasporangia:
sac within which zoospores form, especially when water is cooled to about 10°C below ambient temperature; in solid substrates, sporangia usually germinate by germ tubes
sometimes formed just below the terminal, primary sporangiumsporangium:
sac within which zoospores form, especially when water is cooled to about 10°C below ambient temperature; in solid substrates, sporangia usually germinate by germ tubes
forming a “twin” arrangement. Hyphal swellings elongate formed in sporangial hyphaehyphae:
single, tubular filament of a fungal or oomycete thallus; the basic structural unit of a fungus or oomycete
and in myceliamycelia:
mass of hyphae constituting the body, or thallus, of fungi and oomycetes; in <em>Phytophthora</em> species, mycelia is coenocytic
and are widely spaced catenulatecatenulate:
having a chain-like form
and clustered intercalaryintercalary:
positioned within a hypha (cf. terminal)
. ChlamydosporesChlamydospores:
an asexual spore with a thickened inner wall&nbsp;that is delimited from the mycelium by a septum; may be terminal or intercalary, and survives for long periods in soil
absent.

Sexual phase

Sterile.

Most typical characters

Phytophthora gemini is characterized by the “twin” arrangement of the sporangiasporangia:
sac within which zoospores form, especially when water is cooled to about 10°C below ambient temperature; in solid substrates, sporangia usually germinate by germ tubes
and possession of elongate catenulatecatenulate:
having a chain-like form
hyphal swellings formed in sporangial hyphaehyphae:
single, tubular filament of a fungal or oomycete thallus; the basic structural unit of a fungus or oomycete
and in myceliamycelia:
mass of hyphae constituting the body, or thallus, of fungi and oomycetes; in <em>Phytophthora</em> species, mycelia is coenocytic
.

Additional specimen(s) evaluated

Phytophthora gemini ex-type CPHST BL 96, duplicate of P15880 (World Phytophthora Collection), which is a duplicate of CBS 123381

Hosts and distribution

NOT FOUND as of June 2018 in U.S. National Fungus Collections Nomenclature Database.

Additional info:
Substrate: rotten leaves
Hosts: Zostera marina

Additional references and links

 

 

Fact sheet author

Z. Gloria Abad, Ph.D., USDA-APHIS-PPQ-S&T Plant Pathogen Confirmatory Diagnostics Laboratory (PPCDL), United States of America.