Name and publication

Phytophthora stricta Xiao Yang, W.E. Copes & C.X. Hong (2014)

Yang X, Copes WE, and Hong C. 2014. Two novel species representing a new cladeclade:
a taxonomic group of organisms classified together on the basis of homologous features traced to a common ancestor
and cluster of Phytophthora. Fungal Biology 118: 72–82.

Corresponding author: Xiao Yang yxiao9@vt.edu

Nomenclature

from Yang et al. (2014)

Mycobank

MB804933

Etymology

‘Stricta' refers to the constrictions of sporangiophores.

Typification

Type: UNITED STATES OF AMERICA, recovered from the surface water in a nursery reservoir, Mississippi, February, 2012; holotype ATCC MYA-4944

Ex-type 58A1

Sequences for ex-type in original manuscript: 58A1 = ITS rDNA KF192694, Cox 1 (Kroon et al 2004) KF192702

Ex-type in other collections

(ET) NRRL 64261, MYA-4944 (MCI), WPC P19972, S&T BL 127 (Abad), 58A1 (Hong)

Molecular identification

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

Phytophthora stricta isolate CPHST BL 127 (= P19972 WPC) = ITS rDNA MG865589, COI MH136981

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 stricta CPHST BL 127
• NCBI: Phytophthora stricta 58A1
• EPPO-Q-bank: Phytophthora stricta
• BOLDSYSTEMS: Phytophthora stricta (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
17

Morphological identification

adapted from Yang et al. (2014)

Colonies and cardinal temperatures

Colony colony:
assemblage of hyphae which usually develops form a single source and grows in a coordinated way
morphology on PDA, V8A, MEA with no distinct pattern. Minimum growth temperature 9°C, optimum 25–30°C, and maximum 33°C.

Conditions for growth and sporulation

Sporangia produced overnight in 1.5 % soil water extract solution. Most isolates are A1, and gametangiagametangia:
part of hypha specialized for fusion in sexual reproduction (see antheridium and oogonium)
are produced in dual cultures with Phytophthora cinnamomi (A2) and Phytophthora meadii (A2).

Asexual phase

Sporangia nonpapillate, sometimes caducouscaducous:
pertaining to sporangia that become dislodged readily (i.e. deciduous) and separate from the sporangiophore (cf. persistent)
with short and long pedicels; ovoidovoid:
egg-shaped, with the widest part at the base of the sporangium and the narrow part at the apex
, limoniform, obpyriformobpyriform:
inversely pear-shaped, i.e. with the widest part at the point of attachment (cf. pyriform)
, 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
, pyriformpyriform:
pear-shaped, with the narrowest part at the base (cf. obpyriform)
, and obovoidobovoid:
inversely egg-shaped; ovoid, but with the widest part at the apex
(av. 62 L x 35 W µm) with internal and nested proliferationnested proliferation:
a type of internal proliferation where a new sporangium develops successively inside the old sporangium after it has emptied
, sometimes with 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 in unbranched sporangiophores; sometimes with one to three constrictions in areas were the pedicelpedicel:
the hyphal base of a sporangium that remains attached after the sporangium separates, or is shed, from the sporangiophore; the pedicel may be short (< 5 µm), medium (5–20 µm), or long (> 20 µm)
gets broken. Hyphal swellings absent. 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
terminal, spherical (av. 35 µm diam) or peanut-shaped.

Sexual phase

Heterothallic. Oogonia smooth-walled, turning gold at maturation, globoseglobose:
having a rounded form resembling that of a sphere
(av. 29 µm diam); antheridiaantheridia:
the male gametangium; a multinucleate, swollen hyphal tip affixed firmly to the wall of the female gametangium (the oogonium)
amphigynousamphigynous:
pertaining to the sexual stage in which the antheridium completely surrounds the stalk of the oogonium (cf. paragynous)
, often cylindrical (av.19 L x 15 W µm); oosporesoospores:
zygote or thick-walled spore that forms within the oogonium after fertilization by the antheridium; may be long-lived
pleroticplerotic:
pertaining to an oospore that fills the oogonium (cf. aplerotic)
(av. 25 µm diam), sometimes with two ooplasts or aborted.

Most typical characters

Phytophthora stricta can be distinguished by the shape of the big cylindrical antheridiaantheridia:
the male gametangium; a multinucleate, swollen hyphal tip affixed firmly to the wall of the female gametangium (the oogonium)
.

Additional specimen(s) evaluated

Phytophthora stricta ex-type CPHST BL 127, duplicate of P19972 (World Phytophthora Collection), which is a duplicate of ATCC MYA-4944

Hosts and distribution

Distribution: North America (USA: CT, MS, VA)
Substrate: isolated from water

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

Additional references and links

 

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

 

• Google All Phytophthora stricta
• Google Images Phytophthora stricta
• Google Scholar Phytophthora stricta

Fact sheet author

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