Phytophthora has been rebuilt to fix security-related problems and to restore GIS tools. These tools allow users to visualize the geospatial, temporal, and environmental contexts of Phytophthora discoveries. The next phase is to update species information and add data derived from large-scale surveys. If you have suggestions and requests to make the database better, please contact Seogchan Kang (sxk55@psu.edu).
Genus wide phylogeny for Phytophthora using four mitochondrial loci (cox2, nad9, rps10 and secY; 2,373 nucleotides). Maximum likelihood branch lengths shown. Numbers on nodes represent bootstrap support values for maximum likelihood (top), maximum parsimony (middle) and Bayesian posterior probabilities as percentages (bottom). Nodes receiving significant support (>95%) in all analysis are marked with an asterisk (*). Scale bar indicates number of substitutions per site.(Martin, Blair and Coffey, unpublished).
[ Click the tree to enlarge it. ]
Phytophthora ilicis Buddenhagen & R.A. Young 1957 (Oomycetes, Pythiales)
Notes: Waterhouse (1970) erroneously listed this as an invalid name, lacking citation of a type specimen, but the Code does not require citation of the type in publications previous to 1958 (Art. 37.1).
Distribution: Europe (UK), North America (Canada, USA).
Substrate: Leaves, twigs.
Disease Note: Leaf and twig blight.
Host: Ilex spp. (Aquifoliaceae).
Supporting Literature:
Buddenhagen, I.W., and Young, R.A. 1957. A leaf and twig disease of English holly caused by Phytophthora ilicis n. sp. Phytopathology 47: 95-101
Erwin, D.C., and Ribeiro, O.K. 1996. Phytophthora Diseases Worldwide. APS Press, St. Paul, Minnesota, 562 pages.
Kroon, L.P.N.M., Bakker, F.T., van den Bosch, G.B.M., Bonants, P.J.M., and Flier, W.G. 2004. Phylogenetic analysis of Phytophthora species based on mitochondrial and nuclear DNS sequences. Fungal Genet. Biol. 41: 766-782
Waterhouse, G.M. 1970. The genus Phytophthora de Bary. Mycol. Pap. 122: 1-59
Updated on Jun 14, 2006
P. ilicis is classified in group IV (Stamps et al. 1990). The morphology of P. ilicis is shown in Figure 1 and Figure 2. See Tables 4.2 and 4.3 in Phytophthora Diseases Worldwide (Erwin and Ribeiro 1996) for tabular keys.
1. Sporangia
Sporangia are obpyriform, semipapillate, caducous (pedicels 5 to 15 µm long), 30 to 50 x 18 to 30 µm (average 39 x 24) on holly leaves, 26 x 18 µm in distilled water, and 39 x 29 µm in Petri\'s mineral solution. Length-breadth ratio ranges from 1.3:1 to 1.6:1 (Figure 1). Sporangiophores are sympodial.
2. Chlamydospores
Chlamydospores produced by this species are rare.
3. Sex Organs
P. ilicis is homothallic; antheridia are amphigynous; oogonia have tapered bases, 25 to 32 µm in diameter (average 27 µm) in leaves, 17 to 28 µm in diameter (average 25 µm) in pea broth; oospores are plerotic, 18 to 26 µm in diameter (average 21 µm) in leaves, 15 to 23 µm (average 20 µm) in pea broth.
4. Growth Temperatures
The minimum temperature for growth is 5°C, optimum 20°C, and maximum 25°C.
Nomenclature information was provided by the the Systematic Botany and Mycology Laboratory in USDA-ARS.
Isolate list