Phytophthora cambivora

Vannini, A. and Vettraino, A. 2011. Phytophthora cambivora. Forest Phytophthoras 1(1). doi: 10.5399/osu/fp.1.1.1811

Phytophthora cambivora


Phytophthora cambivora (Petri) Buisman (1927) causes root rot and stem canker on several forest species in Europe and North America.  It causes ink disease of chestnut (Day 1938, Vannini & Vettraino 2001, Vettraino et al. 2005).  Other hardwoods, especially members of the Fagaceae, such as European beech, chinquapin, and tanoak (rarely), are affected (Belisario & Maccaroni 2006, Nelson et al. 2010, Orlikowski et al. 2006, Reeser et al. 2007, Saavedra et al. 2007, Schmitz et al. 2007).

Etymology: combining the Latin for "cambium" and “devouring.”


Phytophthora cambivora is heterothallic, forming characteristic warty, or bullate oogonia with 2-celled antheridia when paired with the opposite mating type. Sporangia are nonpapillate, about  55–65 μm by 40–45 μm, and broadly ellipsoid or ovoid. They are persistent, on simple, unbranched sporangiophores and exhibit internal, often nested proliferation as well as external extension of the sporangiophore. Chlamydospores are absent. Hyphal swellings are rare.

Bullate oogonium and two-celled amphigynous antheridium (top), hyphal swellings (bottom).
Ovoid non-papillate sporangium (left), empty sporangia showing nested internal proliferation (right).


Phytophthora cambivora is in phylogenetic clade 7, with P. cinnamomi, with which it shares many features. It has been implicated in the complex hybrid genealogy of P. alni (Brasier & Kirk 2001). Different mating types predominate on different hosts and in different regions: isolates of P. cambivora from chestnut in Europe and from chinquapin in Oregon are mostly mating type A2 (Saavedra et al. 2007, Vettraino et al. 2005); isolates from other forest hosts in western North America are A1.

Phylogenetic tree from (Blair et al 2008).


Phytophthora cambivora grows dense aerial, fluffy colonies without pattern on most agar media. It is relatively fast growing (growth at 20°C on V8 agar 5.6 mm/d, on cornmeal agar with 20 ppm β-sitosterol 5.1 mm/d, on cornmeal agar with pimaricin, ampicillin, and rifampicin 4.6 mm/d, potato dextrose agar (PDA) 3.4 mm/d). The optimum temperature for growth is ca. 22–24°C, min. ca. 2°C, max. ca. 32°C.

Colony morphology at 14 days on PDA (left) and V8 (right).

Distinguishing characteristics for identification

Phytophthora cambivora is relatively easy to identify, especially if the typical bullate oogonia and 2-celled antheridia are induced in a mating test. Look-alike P. alni is homothallic. The fluffy, patternless colony morphology on agar is distinctive. Sporangia are usually slow to form, and not abundant. They are non-papillate and generally non-descript.  Phytophthora cambivora is very similar in appearance to P. cinnamomi and P. cryptogea, but can usually be distinguished by lack of chlamydospores.

The searchable web-based database Phytophthora-ID is useful for rapid identification of Phytophthora species based on sequencing of the ITS or Cox spacer regions, followed by BLAST searching the database. Phytophthora-ID maintains a database of sequences that is selective for sequence accessions that come from trusted sources including published, peer-reviewed studies whenever possible.

Disease History

Blepharospora cambivora was recognized by Petri in 1917 as the cause of “Maladie de la encre,” or ink disease of European chestnut (Day 1938, Vannini & Vettraino 2001). It was soon recognized as a Phytophthora species and transferred to that genus by Christina Buisman.  Today it is known to be a common pathogen in much of Europe on hardwood forest trees, especially members of the Fagaceae, including chestnut and beech (Belisario & Maccaroni 2006, Cerny et al. 2008, Jung et al. 2005, Nelson et al. 2010, Orlikowski et al. 2006, Schmitz et al. 2007, Vannini & Vettraino 2001, Vettraino et al. 2005). In North America, it is also implicated in root rot of chestnut in the SE United States, but P. cinnamomi proved to be most frequently involved. In 2000 P. cambivora was associated with death of chinquapin (Chrysolepis chrysophylla) forest trees in south central Oregon (Saavedra et al. 2007). It is occasionally isolated from basal cankers on tanoaks (Reeser et al. 2007).  P. cambivora is also known as a pathogen of fruit trees.

Impacts in the Forest

Phytophthora cambivora, as the cause of ink disease in Europe, may have dramatic economic and ecological consequences in chestnut orchards, high forest, coppices or natural lands, especially in France, Italy and Greece (Vannini & Vettraino 2001, Vettraino et al. 2005). In Germany and nearby countries it is important among the group of Phytophthora species causing bleeding cankers and ultimately mortality on European beech (Belisario & Maccaroni 2006, Jung et al. 2005, Nelson et al. 2010, Orlikowski et al. 2006, Schmitz et al. 2007). It is having a similar impact, although in a much more limited area, on chinquapin in Oregon (Saavedra et al. 2007). P. cambivora causes scattered mortality of other forest trees in Europe (Greslebin et al. 2005, Talgø et al. 2006, Vettraino et al. 2003, Yakabe et al. 2009). P. cambivora has been recovered from forest soils and streams throughout western Oregon, as well as oak forest soils in the eastern United States and Europe, although usually there are no associated symptoms on the trees (Balci et al. 2007, Reeser et al. 2011, Vettraino et al. 2002).

Forest and Wildland Hosts and Symptoms

P. cambivora causes root rot and stem cankers on several forest tree species. The symptoms of ink disease of chestnut are typical. Necrosis of feeder or main roots may spread to the collar and the trunk, resulting in the cortical flame shaped lesions with black exudates for which the disease is named (Vannini & Vettraino 2001, Vettraino et al. 2005). Root destruction leads to above ground symptoms, including chlorosis, microphylly, and wilting. These can be followed by a quick or a progressive death depending on the environmental conditions (Vannini & Vettraino 2001, Vettraino et al. 2005). Affected chinquapin trees exhibit girdling basal cankers marked by red-brown inner bark tissues, extending upward from necrotic main roots (Reeser et al. 2007). Cankers on beech in Europe and elsewhere are also marked by bleeding spots but the discoloration of inner bark in active lesions is less dramatic. Bole cankers caused by P. cambivora on tanoak are infrequent, but indistinguishable from those caused by P. ramorum (Reeser et al. 2007).

Crown (left) and collar (right) symptoms of ink disease on sweet chestnut.
Host Latin Name Host Common Name Symptoms Habitat Region
Abies spp. True firs Root rot Christmas trees Norway, Poland, USA
Acer spp. Maple Canker Forest, Parklands Europe
Aesculus hyppocastanum Horse chestnut Root rot Austria, England
Alnus glutinosa European common alder Canker Germany, Poland
Castanea crenata Japanese chestnut Root rot Japan
Castanea dentata American chestnut Root rot USA
Castanea sativa Chestnut, Sweet chestnut Canker, Root rot Forest, Plantations Czech Republic, England, France, Greece, Hungary, Italy, Portugal, Romania, Slovakia, Spain, Switzerland, Turkey
Chrysolepis chrysophylla Chinquapin Canker Forest USA - Pacific Northwest
Fagus sylvatica Beech Root rot Forest, Parklands Austria, Belgium, Czech Republic, Germany, Greece, Italy, Poland, Romania
Juglans spp. Walnut Canker, Root rot Plantations Europe, USA
Notholithocarpus densiflorus Tanoak Canker Forest USA - Pacific Northwest
Platanus orientalis Sycamore Canker Forest, Parklands Europe
Quercus spp. Deciduous oaks, Oak Root rot Forest Czech Republic, France, Germany, Italy, United Kingdom, USA

Educational and Management Materials

Selected References

Balci, Y, Balci S, Eggers J, MacDonald WL, Juzwik J, Long RP, Gottschalk KW. 2007. Phytophthora spp. associated with forest soils in eastern and north-central U.S. oak ecosystems. Plant Disease 91:705-710.

Belisario, A, Maccaroni M, Vettorazzo M. 2006. First report of Phytophthora cambivora causing bleeding cankers and dieback on beech (Fagus sylvatica) in Italy. Plant Disease 90:1362-1362.

Blair, JE, Coffey MD, Park S-Y, Geiser DM, Kang S. 2008. A multi-locus phylogeny for Phytophthora utilizing markers derived from complete genome sequences. Fungal Genetics and Biology 45:266-277. doi:10.1016/j.fgb.2007.10.010

Brasier, CM, Kirk SA. 2001. Comparative aggressiveness of standard and variant hybrid alder phytophthoras, Phytophthora cambivora and other Phytophthora species on bark of Alnus, Quercus and other woody hosts. Plant Pathology 50:218. doi:10.1046/j.1365-3059.2001.00553.x

Buisman, CJ. 1927. Root rots caused by Phycomycetes. Thesis, University of Utrecht. 51 pp. Meded. Phytopath. Lab. Willie Commelin Scholten Baarn 11: 4,7.

Cerny, K, Gregorová B, Strnadová V, Tomšovsky M, Holub V, Gabrielová Š. 2008. Phytophthora cambivora causing ink disease of sweet chestnut recorded in the Czech Republic. Czech Mycology 60(2):265–274.

Chastagner, GA, Hamm PB, Riley KL. 1995. Symptoms and Phytophthora spp. associated with root rot and stem canker of noble fir Christmas trees in the Pacific Northwest. Plant Disease 79:290–293.

Day, WR. 1938. Root-rot of sweet chestnut and beech caused by species of Phytophthora. Forestry 12:101–116.

Greslebin, AG, Hansen EM, Winton LM, Rajchenberg M. 2005. Phytophthora species from declining Austrocedrus chilensis forests in Patagonia, Argentina. Mycologia 97:218-228. doi:10.3852/mycologia.97.1.218

Grünwald, NJ, Martin FN, Larsen MM, Sullivan CM, Press CM, Coffey MD, Hansen EM, Parke JL. 2011. a sequence-based Phytophthora identification tool. Plant Disease 95:337-342.

Ho, HH. 1981. Synoptic keys to the species of Phytophthora. Mycologia 73(4):705-714. doi:10.2307/3759497

Jung, T, Hudler GW, Jensen-Tracy SL, Griffiths HM, Fleischmann F, Osswald W. 2005. Involvement of Phytophthora species in the decline of European beech in Europe and the USA. Mycologist 19:159-166. doi:10.1017/S0269915X05004052

Nelson, A, Weiland G, Hudler G. 2010. Prevalence, distribution and identification of Phytophthora species from bleeding canker on European beech. Phytopathology 28:150–158.

Orlikowski, LB, Oszako T, Szkuta G. 2006. First record on Phytophthora spp. associated with the decline of European beech stand in south-west Poland. Phytopatologia Polonica 42:37-46.

Reeser, P, Sutton W, Hansen EM. 2007. Phytophthora species associated with stem cankers on tanoak in southwestern Oregon. Pages 227-229 in: Proceedings of the Sudden Oak Death Third Science Symposium (SJ Frankel, JT Kliejunas, and KM Palmieri, tech. coords.). Gen.Tech. Report PSW-GTR-214. U.S. Dept. of Agriculture, Forest Service, Pacific Southwest Res. Station, Albany, CA.

Reeser, PW, Sutton W, Hansen EM, Remigi P, Adams GC. 2011. Phytophthora species in forest streams in Oregon and Alaska. Mycologia 103:22-35. doi:10.3852/10-013

Saavedra, A, Hansen EM, Goheen DJ. 2007. Phytophthora cambivora in Oregon and its pathogenicity to Chrysolepis chrysophylla. Forest Pathology 37:409-419. doi:10.1111/j.1439-0329.2007.00515.x

Schmitz, S, Zini J, Chandelier A. 2007. Involvement of Phytophthora species in the decline of beech Fagus sylvatica in Wallonia (Belgium). Communications in Agricultural and Applied Biological Sciences 72:879-85.

Talgø, V, Herrero M, Toppe B, Klemsdal S, Stensvand A. 2006. First report of root rot and stem canker caused by Phytophthora cambivora on noble fir (Abies procera) for bough production in Norway. Plant Disease 90:682-682.

Vannini, A, Vettraino AM. 2001. Ink disease in chestnuts: impact on the European chestnut. Forest Snow and Landscape Research 76:345–350.

Vettraino, AM, Barzanti GP, Bianco MC, Ragazzi A, Capretti P, Paoletti E, Luisi N, Anselmi N, Vannini A. 2002. Occurrence of Phytophthora species in oak stands in Italy and their association with declining oak trees. Forest Pathology 32:19-28. doi:10.1046/j.1439-0329.2002.00264.x

Vettraino, AM, Belisario A, Maccaroni M, Vannini A. 2003. Evaluation of root damage to English walnut caused by five Phytophthora species. Plant Pathology 52:491-495. doi:10.1046/j.1365-3059.2003.00864.x

Vettraino, A, Morel O, Perlerou C, Robin C, Diamandis S, Vannini A. 2005. Occurrence and distribution of Phytophthora; species in European chestnut stands, and their association with Ink Disease and crown decline. European Journal of Plant Pathology 111:169-180. doi:10.1007/s10658-004-1882-0

Yakabe, LE, Blomquist CL, Thomas SL, MacDonald JD. 2009. Identification and frequency of Phytophthora species associated with foliar diseases in California ornamental nurseries. Plant Disease 93:883-890.