Phytophthora botryosa

Name and publication

Phytophthora botryosa Chee (1969)

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


from Chee (1969)




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

CBS 581.69 = P3425 (WPC), ATCC 58105, H3-1, Chee 1075, CPHST BL 132 (Abad), 62C6 (Yang)

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

Sequences for ex-type in other sources
Position in ITS phylogenetic tree

Clade 2a

Morphological identification

Colonies and cardinal temperatures

Cultures in V-8 agar slightly chrysanthemum, in PDA with no distinctive pattern and with little aerial mycelium. Minimum temperature for growth 9°C, optimum 26°C, maximum 32°C.

Asexual phase

Sporangia semipapillate, caducous with medium pedicel (5–20 µm long), oval or occasionally ovoid (28 x 15 µm) produced in simple sympodial sporangiophores. Sporangia produced abundantly in botryose clumps in average of about 90 sporangia per clump. Hyphal swellings absent. Chlamydospores infrequent, globose, 14–30 µm diam.

Sexual phase

Heterothallic. Although oogonia are rarely produced in single cultures, they are abundant when A1 and A2 isolates are grown together. Oogonia smooth-walled, 25–30 µm diam.; antheridia amphigynous, 14 x 13 µm; oospores 22–24 µm diam.

Most typical characters

Phytophthora botryosa is characterized by the presence of sporangia 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

Fact sheet author

Z. Gloria Abad, Ph.D., USDA-APHIS-PPQ-S&T Beltsville Laboratory, United States of America