Phytophthora vignae (in progress - Abad et al. 2023b)


   Phytophthora  spp. in subclade 7b:  portion of the seven-loci ML phylogeny featuring the type cultures of 212 described species (by T. Bourret). Notice the position of   P. vignae  selected specimen WPC P3019 = S&T BL 30 . Gloria Abad, USDA S&T.
Phytophthora spp. in subclade 7b: portion of the seven-loci ML phylogeny featuring the type cultures of 212 described species (by T. Bourret). Notice the position of P. vignae selected specimen WPC P3019 = S&T BL 30. Gloria Abad, USDA S&T.
   Phytophthora  spp. in subclade 7b:  Morphological Tabular key (PDF) and Tabular key legends (PDF) in IDphy2 KEY SECTION. Notice the data of   P. vignae  selected specimen WPC P3019 = S&T BL 30 . Gloria Abad, USDA S&T.
Phytophthora spp. in subclade 7b: Morphological Tabular key (PDF) and Tabular key legends (PDF) in IDphy2 KEY SECTION. Notice the data of P. vignae selected specimen WPC P3019 = S&T BL 30. Gloria Abad, USDA S&T.

Name and publication

Phytophthora vignae Purss (1957)

Purss GS. 1957. Stem rot, a disease of cowpeas caused by an undescribed species of Phytophthora. Queensland J. Agric. Anim. Sci. 14: 125–154.

Nomenclature

Mycobank

MB 303625

Typification

from Purss (1957)

Type: AUSTRALIA, collected from stem and root tissue of cowpea [Vigna sinensis (L.) Endl. Ex Hassk.] in Stuart Valley, Queensland

Ex-type: LOST

Well-authenticated specimen(s) selected by Gloria Abad: 
Selected specimen #1: CPHST BL 30 = P3019 (WPC) from AUSTRALIA in Vigna unguiculata (race 1)

Selected specimen in other collections

(SE) WPC P3019, S&T BL 30 (Abad), Pegg 20853 

Molecular identification

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

Phytophthora vignae isolate CPHST BL 30 (= P3019 WPC) = ITS rDNA MG865598, COI MH136989

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 selected specimen in other sources
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
7b

Morphological identification

Colonies and cardinal temperatures

Colony colony:
assemblage of hyphae which usually develops form a single source and grows in a coordinated way
morphology on CMA, PDA, V-8 with no distinct pattern. Minimum growth temperature 10°C, optimum 24°C, and maximum 32°C.

Conditions for growth and sporulation

Sporangia produced in distilled water following growth in pea broth. ChlamydosporesChlamydospores:
an asexual spore with a thickened inner wall that is delimited from the mycelium by a septum; may be terminal or intercalary, and survives for long periods in soil
and hyphal swellings produced in CMA and oat meal agar. Sexual stage produced abundantly in host tissue, oat meal agar, and corn meal agar.

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
 nonpapillate; 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
to obpyriformobpyriform:
inversely pear-shaped, i.e. with the widest part at the point of attachment (cf. pyriform)
(27–72 µm length x 15–54 µm width) with tapered basetapered base:
pertaining to the base of a sporangium or oogonium; funnel-shaped
and showing nested and extended proliferationextended proliferation:
a type of internal proliferation in which the sporangiophore originates from inside of an empty sporangium, and continues to grow through and out of the old sporangium
; produced in unbranched and sometimes in simple sympodial sporangiophores. Hyphal swellings irregular, terminal, and intercalaryintercalary:
positioned within a hypha (cf. terminal)
. ChlamydosporesChlamydospores:
an asexual spore with a thickened inner wall that is delimited from the mycelium by a septum; may be terminal or intercalary, and survives for long periods in soil
terminal and intercalaryintercalary:
positioned within a hypha (cf. terminal)
, globoseglobose:
having a rounded form resembling that of a sphere
(12–21 µm).

Sexual phase

Homothallic. OogoniaOogonia:
the female gametangium in which the oospore forms after fertilization by the antheridium
smooth-walled (27–42 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)
, spherical to ovate; oosporesoospores:
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)
(24–32 µm diam.).

Specimen(s) evaluated

Phytophthora vignae CPHST BL 30, duplicate of P3019 (World Phytophthora Collection)

Hosts and distribution

Distribution: Asia, Australia
Substrate: stems, soil; also leaves, roots
Disease note: stem rot, leaf spot, may completely destroy root system
Host: natural hosts: Vigna unguiculata (Vigna sinensis, Fabaceae); Vigna angularis; (=Phaseolus angularis, Fabaceae, sometimes referred to Phytophthora vignae f.sp. adzukicola. Malus domestica (apple, Rosaceae) fruits can be infected when inoculated. Reports from a few other taxa.

Retrieved February 01, 2018 rom 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 Plant Pathogen Confirmatory Diagnostics Laboratory (PPCDL), United States of America.