Name and publication

Phytophthora thermophila T. Jung, M.J.C. Stukely & T.I. Burgess (2011)

Jung T, Stukely MJC, Hardy GE St, White MD, Paap T, Dunstan WA, and Burgess TI. 2011. Multiple new Phytophthora species from ITS Cladeclade:
a taxonomic group of organisms classified together on the basis of homologous features traced to a common ancestor
6 associated with natural ecosystems in Australia: evolutionary and ecological implications. Persoonia 13: 13–39.

Nomenclature

from Jung et al. (2011)

Mycobank

MB518766

Typification

Type: AUSTRALIA, Western Australia, Dwellingup, from rhizosphere soil of declining Eucalyptus marginata, 2004, holotype MURU 464 (dried culture on V8A, Herbarium of Murdoch University, Western Australia)

Ex-type: CBS 127954 = VHS 13530

Sequences for ex-type in original manuscript: CBS 127954 = HSP90 HQ012916, cox1 HQ012872

Ex-type in other collections

(ET) CBS 127954,  NRRL 64163, VHS13530, WPC P19593, S&T BL 77 (Abad), 55C1 (Hong)

Molecular identification

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

Phytophthora thermophila isolate CPHST BL 77 (= P19593 WPC) = ITS rDNA MG865593, COI MH136985

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

• NCBI: Phytophthora thermophila CPHST BL 77
• NCBI: Phytophthora thermophila CBS 127954
• EPPO-Q-bank: Phytophthora thermophila CBS 127954 
• BOLDSYSTEMS: Phytophthora thermophila (barcoding COI & ITS)

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
6b

Morphological identification

Colonies and cardinal temperatures

Colony colony:
assemblage of hyphae which usually develops form a single source and grows in a coordinated way
morphology is stellate to petaloid on V8A, CA, and MEA. Colonies are irregular and dense-felty on PDA. Minimum growth temperature 10°C, optimum 33°C, and maximum 35°C.

Conditions for growth and sporulation

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
 are produced in water cultures (soil extract or river water) and not observed in solid media. OogoniaOogonia:
the female gametangium in which the oospore forms after fertilization by the antheridium
observed for one isolate when flooded with nonsterile soil filtrate.

Asexual phase

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
 are nonpapillatenonpapillate:
pertaining to the production of a non-distinct, or inconspicuous, papilla at the distal end of the sporangium (cf. papillate and semipapillate)
, persistentpersistent:
pertaining to sporangia that remain attached to the sporangiophore and do not separate or detach easily (cf. caducous)
, ovoidovoid:
egg-shaped, with the widest part at the base of the sporangium and the narrow part at the apex
to elongated ovoidovoid:
egg-shaped, with the widest part at the base of the sporangium and the narrow part at the apex
, or limoniform with average dimensions of 44.8 ± 6.3 x 25.7 ± 3.9 µm (overall range 29.0–64.8 x 15.6–39.3 µm). Sporangiophores in simple sympodiasympodia:
a type of sporangiophore which appears simple, but where each successive sporangium develops on a branch behind and to one side of the previous apex, where growth has already ceased
, and internal proliferationinternal proliferation:
internal proliferation occurs when the sporangiophore continues to grow through an empty sporangium
, both nested and extended, occurs in chains. Hyphal swellings globose or elongated. ChlamydosporesChlamydospores:
an asexual spore with a thickened inner wall that is delimited from the mycelium by a septum; may be terminal or intercalary, and survives for long periods in soil
 globose, 41.5 ± 14.7 µm.

Sexual phase

Homothallichomothallic:
pertaining to sexual reproduction that can take place within a single thallus (i.e. self-fertile, non-outcrossing) (cf. heterothallic).
although oogoniaoogonia:
the female gametangium in which the oospore forms after fertilization by the antheridium
only observed for one isolate. OogoniaOogonia:
the female gametangium in which the oospore forms after fertilization by the antheridium
with wavy walls, average size 31.1 ± 2.5 mm (27.2–38.0 µm) OosporesOospores:
zygote or thick-walled spore that forms within the oogonium after fertilization by the antheridium; may be long-lived
are highly apleroticaplerotic:
pertaining to a mature oospore that does not fill the oogonium; i.e. there is room left between the oospore wall and oogonium wall (cf. plerotic)
, globoseglobose:
having a rounded form resembling that of a sphere
, average size 23.6 ± 2.2 µm (0.4–29.7). AntheridiaAntheridia:
the male gametangium; a multinucleate, swollen hyphal tip affixed firmly to the wall of the female gametangium (the oogonium)
 are paragynousparagynous:
pertaining to the sexual stage in which the antheridium is attached to the side of the oogonium (cf. amphigynous)
.

Most typical characters

Phytophthora thermophila is in a species cluster with P. amnicola, P. fluvialis, P. moyootj, and P. litoralis, all recovered from waterways in Western Australia. Of all these species, P. thermophila is the only one to occasionally reproduce sexually in culture.

Specimen(s) evaluated

Australia, Western Australia, Dwellingup, from rhizosphere soil of declining Eucalyptus marginata, 2004; VHS 13530 = CBS 127954; VHS 21998 = CBS 127951; VHS 13567; VHS 13761; Pemberton, from rhizosphere soil of dying Banksia grandis, 2006, VHS 16164; Quinninup, from native forest, 1998, VHS 3655; Manjimup, from native forest, 2000; VHS 7474; Brunswick, from stream baiting, 2008, MUCC 764

ex-type CPHST BL 77 = P19593 (WPC)

Hosts and distribution

Distribution: Australia
Substrate: soil associated with dying plants

Retrieved February 01, 2018 from U.S. National Fungus Collections Nomenclature Database.

Additional info:
Distribution: Western Australia, Tasmania
Substrate: roots, collars and rhizosphere soil
Disease note: no pathogenicity trials have been conducted
Hosts: commonly isolated in association with other Phytophthora species in rhizosphere soil collected in wetter areas

Additional references and links

Burgess TI, Webster JL, Ciampini JA, White DW, Hardy GESJ, Stukely MJC (2009) Re-evaluation of Phytophthora species isolated during 30 years of vegetation health surveys in Western Australia using molecular techniques. Plant Disease 93, 215-223.

Hüberli D, Hardy GESJ, White D, Williams N, Burgess TI (2013) Fishing for Phytophthora from Western Australia's waterways: A distribution and diversity survey. Australasian Plant Pathology 42: 251-260.

Nagel JH, Gryzenhout M, Slippers B, Wingfield MJ, Hardy GESJ, Stukely MJC, Burgess TI (2013) Characterization of Phytophthora hybrids from ITS cladeclade:
a taxonomic group of organisms classified together on the basis of homologous features traced to a common ancestor
6 associated with riparian ecosystems in South Africa and Australia. Fungal Biology 117: 329-347.

 

• SMML USDA-ARS: Phytophthora thermophila
• EPPO Global Database: Phytophthora thermophila
• Forest Phytophthoras of the world: Phytophthora thermophila
• CABI Digital Library: Phytophthora thermophila
• Encyclopedia of Life (EOL): Phytophthora thermophila
• Index Fungorum (IF): Phytophthora thermophila

 

• Google All Phytophthora thermophila
• Google Images Phytophthora thermophila
• Google Scholar Phytophthora thermophila

Fact sheet authors

Treena Burgess, Ph.D., Phytophthora Science and Management, Harry Butler Institute, Murdoch University, Australia

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