Phytophthora gemini

Name and publication

Phytophthora gemini Man in ’t Veld, Rosendahl, Brouwer & de Cock (2011)

Man in ’t Veld WA, Rosendahl KC, Brouwer H, and de Cock AW. 2011. Phytophthora gemini sp. nov., a new species isolated from the halophilic plant Zostera marina in the Netherlands. Fungal Biol. 115: 724–732.

Corresponding author:


from Man in ’t Veld et al. (2011)




geminus is twin, refering to two sporangia on one hypha


Type: THE NETHERLANDS, Lake Grevelingen, from Zostera marina, CBS 123381, dried culture, in CBS-KNAW, Fungal Biodiversity Centre, Utrecht, the Netherlands

Ex-type: CBS 123381

Sequences for ex-type in original manuscript: CBS 123381 = ITS rDNA FJ217680

Ex-type in other collections

CBS 123381 = P15880 (WOC/WPC), gs/11917, Phytophthora sp. AL-2010c, Phytophthora sp. WMihV-2008. CPHST BL 96 (Abad)

Molecular identification

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

Phytophthora gemini isolate P15880 = ITS rDNA HQ261693, COI HQ261440

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

Clade 6a

Morphological identification

adapted from Man in ’t Veld et al. (2011)

Colonies and cardinal temperatures

Colony morphology after 7 days on PDA, V-8, MEA with fine chrysanthemum pattern. Minimum growth temperature 5°C, optimum 24–27°C, and maximum 33°C.

Conditions for growth and sporulation

Sporangia formed abundantly in sterile filtered pond water.

Asexual phase

Sporangia nonpapillate; persistent; obovoid, ellipsoid, ovoid, and obpyriform, often with a tapered base (53–31 µm) showing a conspicuous basal plug, and originated in unbranched and simple sympodial sporangiophores. Secondary sporangia sometimes formed just below the terminal, primary sporangium forming a “twin” arrangement. Hyphal swellings elongate formed in sporangial hyphae and in mycelia and are widely spaced catenulate and clustered intercalary. Chlamydospores absent.

Sexual phase


Most typical characters

Phytophthora gemini is characterized by the “twin” arrangement of the sporangia and possession of elongate catenulate hyphal swellings formed in sporangial hyphae and in mycelia.

Additional specimen(s) evaluated

Phytophthora gemini ex-type CPHST BL 96, duplicate of P15880 (World Phytophthora Collection), which is a duplicate of CBS 123381

Hosts and distribution

NOT FOUND as of June 2018 in U.S. National Fungus Collections Nomenclature Database.

Additional info:
Substrate: rotten leaves
Hosts: Zostera marina

Additional references and links

Fact sheet author

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