Phytophthora palmivora (to be redescribed 2022)

Name and publication

Phytophthora palmivora (Butler) Butler (1919)

Butler EJ. 1918–1919. Report of the imperial mycologist, Science Report Institute Pusa. 82 pp.

Nomenclature

Mycobank

MB194605

Synonymy

Pythium palmivorum E.J. Butler, Memoirs of the Department of Agriculture India 1 (5): 82 (1907) [MB170467]
= Phytophthora faberi Maubl. (1909) [MB232306]

Typification

from Butler (1919)

Type: INDIA, Godavery Delta on the East Coast, as Pythium palmivorum Butler 1907

NOTE: According to Butler (1910) the disease was associated with palmyra (Borassus flabelilfer), coconut (Cocos nucifera), areca (Areca catechu), and date (Phoenix sylvestris).

Ex-type: LOST

Well-authenticated specimen(s) selected by Gloria Abad: 

  • Selected specimen #1: CPHST BL 105 = P0633 (WPC) (A2) INDIA from Areca catechu 
  • Selected specimen #2: CPHST BL 106 = P3738 (WPC) (A1) INDONESIA from Cocos nucifera
  • Selected specimen #3: CPHST BL 46 = P0255 (WPC) (A1) COSTA RICA from Theobroma cacao
Selected specimen(s) in other collections

Molecular identification

Voucher sequences for barcoding genes (ITS rDNA and COI) of selected specimens (see Molecular protocols page)

Phytophthora palmivora isolate CPHST BL 105 (= P0633) = ITS rDNA MG865559, COI MH136949

Phytophthora palmivora isolate CPHST BL 106 (= P3738 WPC) = ITS rDNA MG865561, COI MH136951

Phytophthora palmivora isolate CPHST BL 46 (= P0255 WPC) = ITS rDNA MG865560, COI MH136950

Sequences for ex-epitype in other sources
Position in phylogenetic tree

Clade 4

Morphological identification

Colonies and cardinal temperatures

Colonies on V-8 agar, potato dextrose agar, and malt extract agar with no distinctive pattern. Some colonies with slight chrysanthemum pattern (i.e. isolate CPHST-BL 46). Minimum temperature for growth 9°C, optimum 24–30°C, maximum 33°C.

Conditions for growth and sporulation

Chlamydospores are abundantly produced in agar and water cultures.

Asexual phase

Sporangia papillate; caducous with short pedicel; globose, ovoid, obpyriform, ellipsoid, and irregular shapes (27–70 L x 21–46 W µm) originated in simple sympodial sporangiophores. Hyphal swellings globose, subglobose, elongate, and irregular shapes. Chlamydospores globose or subglobose (16–50 L x 16–45 W µm), terminal or intercalary.

Sexual phase

Heterothallic. Oogonia smooth-walled (28–42 µm diam.); antheridia spherical, short cylindrical or ellipsoid (12–21 L x 13–17 W µm), sometimes with spine or digitate projections; oospores plerotic to slightly aplerotic (27–40 µm diam.).

Most typical characters

Phytophthora palmivora is characterized by the shapes of sporangia with short pedicels and the sympodial sporangiophores. The shape of chlamydospores and hyphal swellings are also useful for identification in combination with other characters of the asexual phase.

Specimen(s) evaluated

Phytophthora palmivora CPHST BL 105 (A2) SE1 = P0633 (World Phytophthora Collection)

Phytophthora palmivora CPHST BL 106 (A1) SE2 = P3738 (World Phytophthora Collection)

Phytophthora palmivora CPHST BL 46 SE3 = P0255 (A1) (World Phytophthora Collection)

Hosts and distribution

Distribution: cosmopolitan
Substrate: leaves, buds, stems, fruits, roots
Disease note: black pod and canker of cacao; patch canker, black stripe, and leaf fall of rubber; bud rot of coconut; fruit and stem rot of pawpaw; root rot and damping-off of seedlings (Stamps 1985)
Host: various plant families

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

Additional references and links

Fact sheet author

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