Name and publication

Phytophthora lactucae Bertier, H. Brouwer & De Cock (2013)

Bertier L, Brouwer H, de Cock AWAM, Cooke DEL, Olsson CHB, and Höfte M. 2013. The expansion of Phytophthora Clade 8b: three new species associated with winter grown vegetable crops. Persoonia 31: 63–76. 

Corresponding author: eb.tnegu@etfoh.acinom

Nomenclature

from Bertier et al. (2013)

Mycobank

MB803104

Etymology

named after the host plant, Lactuca sativa (lettuce)

Typification

Type: GREECE, Marathon, Attika, collected from stem of Lactuca sativa cv. Paris Island Cos, by L. Elena in 2001, holotype CBS H-21129 (dried culture)

Ex-type: culture BPIC 1985

Sequences for ex-type in original manuscript: BPIC 1985 = ITS KC478768, Cox1 KC478738

Ex-type in other collections

(ET) BPIC 1985, WPC P19872 P19875, S&T BL113 (Abad), 61F4 (Hong)  

Molecular identification

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

Phytophthora lactucae isolate BPIC 1985 ITS rDNA KC478768

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 lactucae CPHST BL 113
• NCBI: Phytophthora lactucae BPIC 1985
• NCBI:  Phytophthora lactucae 61F4
• EPPO-Q-bank: Phytophthora lactucae BPIC 1985
• BOLDSYSTEMS: Phytophthora lactucae (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
8b

Morphological identification

adapted from Bertier et al. (2013)

Colonies and cardinal temperatures

Colonies on CMA, V8, and PDA with no distinctive colonycolony:
assemblage of hyphae which usually develops form a single source and grows in a coordinated way
pattern. Minimum temperature for growth 0°C, optimum 18°C, and maximum 24°C.

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
semipapillatesemipapillate:
pertaining to the production of shallow having papilla that are not well developed, shallow and less nipple-like than fully papillate structures
, persistentpersistent:
pertaining to sporangia that remain attached to the sporangiophore and do not separate or detach easily (cf. caducous)
, ovoidovoid:
egg-shaped, with the widest part at the base of the sporangium and the narrow part at the apex
, ellipsoidellipsoid:
refers to a solid body that forms an ellipse in the longitudinal plane and a circle in cross section; many fungal spores are ellipsoidal or elliptic
, slightly obpyriformobpyriform:
inversely pear-shaped, i.e. with the widest part at the point of attachment (cf. pyriform)
and asymmetrical shapes, some with tapered bases (28–101 × 18–54 μm) originated in unbranched sporangiophores. Hyphal swellings occur in sparse clusters and are globoseglobose:
having a rounded form resembling that of a sphere
to somewhat angular or irregular in shape. Chlamydospores are rarely produced and are globoseglobose:
having a rounded form resembling that of a sphere
and intercalaryintercalary:
positioned within a hypha (cf. terminal)
.

Sexual phase

Homothallic. OogoniaOogonia:
the female gametangium in which the oospore forms after fertilization by the antheridium
smooth-walled and globoseglobose:
having a rounded form resembling that of a sphere
(22–44.1 × 21–44.1 μm); antheridiaantheridia:
the male gametangium; a multinucleate, swollen hyphal tip affixed firmly to the wall of the female gametangium (the oogonium)
predominantly paragynousparagynous:
pertaining to the sexual stage in which the antheridium is attached to the side of the oogonium (cf. amphigynous)
, but some amphigynousamphigynous:
pertaining to the sexual stage in which the antheridium completely surrounds the stalk of the oogonium (cf. paragynous)
antheridia occur; oosporeoospore:
zygote or thick-walled spore that forms within the oogonium after fertilization by the antheridium; may be long-lived
apleroticaplerotic:
pertaining to a mature oospore that does not fill the oogonium; i.e. there is room left between the oospore wall and oogonium wall (cf. plerotic)
(19–38.7 μm).

Additional specimen(s) evaluated

Phytophthora lactucae ex-type CPHST BL 113, duplicate of P19875 (World Phytophthora Collection), which is a duplicate of ex-type BPIC 1985

Hosts and distribution

Distribution: Europe (Greece)
Substrate: isolated from stem
Host: Lactuca sativa (Asteraceae)

Retrieved January 31, 2018 from U.S. National Fungus Collections Nomenclature Database.

Additional references and links

 

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

 

• Google All Phytophthora lactucae
• Google Images Phytophthora lactucae
• Google Scholar Phytophthora lactucae

Fact sheet author

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