Name and publication

Phytophthora attenuata T. Jung, M. Horta Jung, Scanu & Bakonyi (2017)

Jung T, Jung MH, Scanu B, Seress D, Kovács GM, Maia C, Pérez-Sierra A, Chang T-T, Chandelier A, Heungens K, van Poucke K, Abad-Campos P, Léon M, Cacciola SO, Bakonyi J. 2017. Six new Phytophthora species from ITS Cladeclade:
a taxonomic group of organisms classified together on the basis of homologous features traced to a common ancestor
7a including two sexually functional heterothallicheterothallic:
pertaining to sexual reproduction in which conjugation is possible only through interaction of different thalli (i.e. different mating types) (cf. homothallic)
hybrid species detected in natural ecosystems in Taiwan. Persoonia 38: 100–135.

Corresponding author: trjung@ualg.pt, thomas.jung@mendelu.cz

Nomenclature

from Jung et al. (2017)

Mycobank

MB816566

Etymology

refers to the tapering oogonial stalks (attenuata Lat. = tapering)

Typification

Type: TAIWAN, Sheipa National Park, isolated from rhizosphere soil of a mature Castanopsis carlesii tree, T. Jung, 2013 (CBS H-22552 holotype, dried culture on V8A, Herbarium CBS-KNAW Fungal Biodiversity Centre)

Ex-type: CBS 141199 = TW129.

Sequences for ex-type: Phytophthora attenuata isolate TW129 ITS KU517154, cox1 KU517148

Ex-type in other collections

(ET) CBS 141199, NRRL 64145, TW129, S&T BL 207 (Abad),. 67C5 (Hong) 

Molecular identification

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

Phytophthora attenuata isolate TW129 ITS rDNA KU517154

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 attenuata TW129 
• EPPO-Q-bank: Phytophthora attenuata 
• BOLDSYSTEMS: Phytophthora attenuata 

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
7a

Morphological identification

adapted from Jung et al. (2017)

Colony and cardinal temperature

Colony colony:
assemblage of hyphae which usually develops form a single source and grows in a coordinated way
morphology on V8 agar is faintly striate with limited aerial myceliummycelium:
mass of hyphae constituting the body, or thallus, of fungi and oomycetes; in <em>Phytophthora</em> species, mycelia is coenocytic
, while on malt extract agar and potato dextrose agar it is uniform. Minimum growth temperature 5°C, optimum 25°C, and maximum 30–35°C.

Conditions for growth and sporulation

Sporangia produced abundantly in nonsterile soil extract. GametangiaGametangia:
part of hypha specialized for fusion in sexual reproduction (see antheridium and oogonium)
readily produced on V8A.

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
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
, elongated, obpyriformobpyriform:
inversely pear-shaped, i.e. with the widest part at the point of attachment (cf. pyriform)
, limoniform, 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
, and subglobose (18–79 L x 14-46 W μm); showing internal and extended proliferationextended proliferation:
a type of internal proliferation in which the sporangiophore originates from inside of an empty sporangium, and continues to grow through and out of the old sporangium
and rarely external proliferationexternal proliferation:
formation of a sporangium after a sporangiophore has emerged from beneath and external to an empty sporangium that has previously emitted its zoospores (cf. internal proliferation)
; originated mainly on unbranched sporangiophores and in lax 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
. Hyphal swellings small, limoniform, infrequently observed on sporangiophores. Chlamydospores absent.

Sexual phase

Homothallic. OogoniaOogonia:
the female gametangium in which the oospore forms after fertilization by the antheridium
smooth-walled or sometimes with flexuose or ornamented walls and tapering, often long bases (29–56 μm diam.); antheridiaantheridia:
the male gametangium; a multinucleate, swollen hyphal tip affixed firmly to the wall of the female gametangium (the oogonium)
predominately paragynousparagynous:
pertaining to the sexual stage in which the antheridium is attached to the side of the oogonium (cf. amphigynous)
; oosporesoospores:
zygote or thick-walled spore that forms within the oogonium after fertilization by the antheridium; may be long-lived
aplerotic aplerotic:
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)
(26–45 μm) globoseglobose:
having a rounded form resembling that of a sphere
or rarely elongated.

Hosts and distribution

Distribution: Asia (Taiwan)
Substrate: isolated from rhizosphere soil
Hosts: Castanopsis carlesii (Fagaceae), Chamaecyparis formosensis (Cupressaceae)

Retrieved January 18, 2018 from U.S. National Fungus Collections Nomenclature Database.

Additional references and links

 

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

 

 

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Fact sheet author

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