Name and publication

Phytophthora botryosa Chee (1969)

Chee KH. 1969. Variability of Phytophthora species from Hevea brasiliensis. T. Brit. Mycol. Soc. 52: 425–436.

Nomenclature

from Chee (1969)

Mycobank

MB336993

Typification

Type: MALAYSIA, on leaf petioles of Hevea brasiliensis collected in Perlis, West Malaysia by Chee (- strain, 1075), September 1966, IMI 136915

Ex-type: CBS 581.69 (isolate A2)

Additional isolate in original publication: THAILAND, Chantaburi, from leaf petioles of Hevea brasiliensis (rubber), K. H. Chee, August 1967, IMI 136916 (Chee 1254 +strain) (A1). This isolate corresponds to Phytophthora palmivora, same as CBS 533.92, P3940, ATCC 26480 (G. Abad 11.15.2017). 

Ex-type in other collections

(ET) CBS 581.69 (A2), WPC P3425, ATCC 58105 MCI, CABI IMI136915 (PL), S&T BL 132 (Abad), 62C6 (Hong), H3-1, Chee1075 

Molecular identification

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

Phytophthora botryosa isolate CPHST BL 132 ( = P3425 ) ITS rDNA MK496516, COI MH136855

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 botryosa CPHST BL 132 
• NCBI: Phytophthora botryosa P3425 (NOTE: Sequence JN618768 is incorrect as it corresponds to Phytophthora citrophthora)
• NCBI: Phytophthora botryosa IMI136915
• EPPO-Q-bank: Phytophthora botryosa CBS 581.69 = IMI 136915
• BOLDSYSTEMS: Phytophthora botryosa PHYTO169.10 = P3425, OOMYA197-07 = CBS58169, OOMYA481-08 = CBS58169 (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
2a

Morphological identification

Colonies and cardinal temperatures

Cultures in V-8 agar slightly chrysanthemum, in PDA with no distinctive pattern and with little aerial myceliummycelium:
mass of hyphae constituting the body, or thallus, of fungi and oomycetes; in <em>Phytophthora</em> species, mycelia is coenocytic
. Minimum temperature for growth 9°C, optimum 26°C, maximum 32°C.

Asexual phase

Sporangia semipapillate, caducouscaducous:
pertaining to sporangia that become dislodged readily (i.e. deciduous) and separate from the sporangiophore (cf. persistent)
with medium 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)
(5–20 µm long), oval or occasionally ovoidovoid:
egg-shaped, with the widest part at the base of the sporangium and the narrow part at the apex
(28 x 15 µm) produced in simple sympodial sporangiophores. 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
produced abundantly in botryose clumps in average of about 90 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
per clump. Hyphal swellings absent. Chlamydospores infrequent, globoseglobose:
having a rounded form resembling that of a sphere
, 14–30 µm diam.

Sexual phase

Heterothallicheterothallic:
pertaining to sexual reproduction in which conjugation is possible only through interaction of different thalli (i.e. different mating types) (cf. homothallic)
. Although oogoniaoogonia:
the female gametangium in which the oospore forms after fertilization by the antheridium
are rarely produced in single cultures, they are abundant when A1 and A2 isolates are grown together. Oogonia smooth-walled, 25–30 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)
, 14 x 13 µm; oosporesoospores:
zygote or thick-walled spore that forms within the oogonium after fertilization by the antheridium; may be long-lived
22–24 µm diam.

Most typical characters

Phytophthora botryosa is characterized by the presence of 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
in botryose clumps.

Specimen(s) evaluated

Phytophthora botryosa CPHST BL 132 (Abad) = P3425 [World Phytophthora Collection (WPC) California, USA] duplicate of the ex-type CBS 581.69

CPHST BL 7 (Abad) selected specimen = P6716 [World Phytophthora Collection (WPC) California, USA]

Hosts and distribution

Distribution: Asia (Malaysia, Thailand, Andaman Islands)
Substrate: leaves, seed pods
Disease note: leaf fall and black stripe of Hevea rubber
Hosts: Hevea brasiliensis (Euphorbiaceae), Cocos nucifera (Palmae), Vanilla sp. (Orchidaceae)

Retrieved January 29, 2018 from U.S. National Fungus Collections Nomenclature Database.

Quarantine status

USA: This species was listed as a species of concern during the 2009 Phytophthora prioritization project conducted by USDA APHIS PPQ CPHST PERAL (Schwartzburg et al.).

Additional references and links

 

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

 

 

• Google All Phytophthora botryosa
• Google Images Phytophthora botryosa
• Google Scholar Phytophthora botryosa

 

Fact sheet author

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