Name and publication
Phytophthora cajani Amin, Baldev, & Williams (1978)
Amin KS, Baldev B, and Williams FJ. 1978. Phytophthora cajani, a new species causing stem blight on Cajanus cajan. Mycologia 70: 171–176.
Nomenclature
from Amin et al. (1978)
Mycobank
Typification
Type: INDIA, causing stem blight on Cajanus cajan. Pure cultures have been deposited in the Phytophthora collection, Department of Plant Pathology, West Virginia University, Morgantown, U.S.A. under N516.
NOTE: Specimen N516 is lost at the Department of Plant Pathology, West Virginia University, Morgantown, USA.
Well-authenticated specimen selected by Gloria Abad: CPHST BL 116 = P3105 (WPC)
Selected specimen(s) in other collections
CPHST BL 116 (Abad) = P3105 (WPC) = ATCC 44388, D.C. Erwin P2 from J. Kannaiyan 5, p349 (Gallegly), 45F7 (Yang)
NOTES:
ATCC 44388 as Phytophthora drechsleri var. cajani
Yang et al. 2017 incorrectly indicates that specimen 45F7 is the type of the species.
Molecular identification
Voucher sequences for barcoding genes (ITS rDNA and COI) of selected specimen(s) (see Molecular protocols page)
Phytophthora cajani isolate CPHST BL 116 (= P3105 WPC) = ITS rDNA MG783386, COI MH136859
Additional sequences for molecular identification
Phytophthora cajani isolate P3105 = ITS rDNA HQ261515, COI HQ261262
Sequences for selected specimen in other sources
- NCBI: Phytophthora cajani CPHST BL 116
- NCBI: Phytophthora cajani P3105
- Phytophthora DATABASE: Phytophthora cajani PD-00171 = P3105 WOC/WPC
- EPPO-Q-bank: Phytophthora cajani
- BOLDSYSTEMS: Phytophthora cajani PHYTO157-10 P3105
Position in ITS phylogenetic tree
Clade 7b
Morphological identification
Colonies and cardinal temperatures
Colonies in CMA, V-8, and PDA with no distinctive pattern. Minimum temperature for growth 9°C, optimum 27–33°C, and maximum 36°C.
Asexual phase
Sporangia non-papillate, persistent, ovoid, obpyriform, ellipsoid, blunty ellipsoid (42–83 L x 29–46 W μm); showing internal, external, and nested proliferation; originated in unbranched sporangiophores sometimes showing swellings. Hyphal swellings terminal and intercalary with finger-like projections. Chlamydospores absent.
Sexual phase
Homothallic. Oogonia smooth-walled (37–48 μm diam); antheridia amphyginous, some with digital projections, some bicellular; oospores aplerotic.
NOTES:
Original publication of Amin et al. (1978) indicates the presence of plerotic oospores, however the figures show oogonia with non-differentiated oospores.
Isolate P3105 is indicated as heterothallic A1 type in the WPC. Isolate CPHST-BL #116 (Abad), a duplicate of P3105, is homothallic and produced oospores in single culture in our laboratory (G. Abad 9/17/16).
Most typical characters
Phytophthora cajani is characterized by the presence of marked aplerotic oospores.
Specimen evaluated
Phytophthora cajani CPHST BL 116 (Abad) = P3105 [World Phytophthora Collection (WPC) California, USA]
Hosts and distribution
Distribution: Asia (India)
Substrate: stems, also on branches, petioles, leaves. Roots are not attacked.
Disease note: stem rot and blight
Hosts: Cajanus cajani (Fabaceae)
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
Phytophthora DATABASE: Phytophthora cajani
EPPO-Q-bank: Phytophthora cajani
SMML USDA-ARS: Phytophthora cajani
EPPO Global Database: Phytophthora cajani
CABI Invasive Species Compendium: Phytophthora cajani
Encyclopedia of Life (EOL): Phytophthora cajani
Index Fungorum (IF): Phytophthora cajani
Plantwise Knowledge Bank: *Phytophthora cajani
- Google All Phytophthora cajani
- Google Images Phytophthora cajani
- Google Scholar Phytophthora cajani
Fact sheet author
Z. Gloria Abad, Ph.D., USDA-APHIS-PPQ-S&T Beltsville Laboratory, United States of America