Name and publication

Phytophthora afrocarpa T. Bose & J.M. Hulbert (2021)

Bose T, Hulbert JM, Burgess TI, Paap T, Roets F, Wingfield MJ. 2021. Two novel Phytophthora species from the southern tip of Africa. Mycological Progress 20 (6): 755–767.

Corresponding author: Tanay Bose; Tanay.Bose@fabi.up.ac.za

Nomenclature

Mycobank

MB838532

Etymology

name refers to the tree Afrocarpus falcatus (syn. Podocarpus falcatus) from which the isolates were recovered

Typification

Type: SOUTH AFRICA, Diepwalle Forest, Western Cape Province, from rhizosphere soil of Afrocarpus falcatus (− 33.956555, 23.152709), January 2017, JM Hulbert, holotype PREM63082

Ex-type: culture PPRI 28450 = CMW 54630 = CBS 147467

Sequences of ex-type in manuscript: ITS MT762306, ß-tubulin MT762324, HSP90 MT762333, coxI MT762315

Ex-type in other collections

(ET) CBS 147467, NRRL 64331, PPRI28450, CMW54630, S&T BL 204 (Abad)

Molecular identification

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

Phytophthora afrocarpa ITS rDNA, COI

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 afrocarpa
• EPPO-Q-bank: Phytophthora afrocarpa
• BOLDSYSTEMS: Phytophthora afrocarpa

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
10b

Morphological identification

Colonies and cardinal temperatures

Slow growing species with cottony, chrysanthemum pattern on CA and V8A, stellate on PDA, and immersed on MEA. Minimum growth temperature 4°C, optimum 25°C, and maximum 30°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) and not observed in solid media. OogoniaOogonia:
the female gametangium in which the oospore forms after fertilization by the antheridium
not produced in single or paired cultures.

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
 were non-papillate, persistentpersistent:
pertaining to sporangia that remain attached to the sporangiophore and do not separate or detach easily (cf. caducous)
, and predominantly 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
in shape with internal 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
. 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
averaged 28 x 18.6 µm (overall range 13.3–49.5 x 7.4–31.2 µm). Sporangiophores simple.Hyphal swellings present. 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
present.

Sexual phase

Sterile in culture.

Most typical characters

Phytophthora afrocarpa is a sister species to P. gallica in cladeclade:
a taxonomic group of organisms classified together on the basis of homologous features traced to a common ancestor
10. Both species are sterile in culture, but differ in other morphological features.

Specimen(s) evaluated

South Africa, Diepwalle Forest, Western Cape Province, from rhizosphere soil of Afrocarpus falcatus, 2017, JM Hulbert, CBS 147467; CBS 147590; CBS 147468

Hosts and distribution

Distribution: South Africa
Substrate: roots
Disease note: no diseases recorded
Hosts: Afrocarpus falcatus

Additional references and links

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

Fact sheet author

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.