Verticillium tricorpus

General information about Verticillium tricorpus is provided below. Included are a morphological description, comments about morphologically similar species and phylogenetic affiliation. The data is from Inderbitzin et al. (2011) where additional information can be found. Host range data is from Inderbitzin and Subbarao (2014).

Species description and morphologically similar species

Verticillium tricorpus is morphologically indistinguishable from V. isaacii and V. klebahnii. See those two for descriptions.

Figure 12. Select morphological features of Verticillium tricorpus.

12a. Colony of strain P685 after 10 days on PDA, frontal view. 12b. Colony of strain PD685 after 10 days on PDA, reverse view. 12c. Conidia of strain PD685 after 38 days on PDA. 12d. Resting mycelium of strain PD685 after 38 days on PDA. 12e. Chain of chlamydospores and microsclerotium of strain PD685 after 38 days on PDA. 12f. Microsclerotium of strain PD685 after 38 days on PDA. 12g. Microsclerotium of lectotype specimen IMI 51602. 12h. Yellow-pigmented hypha of strain PD685 after 38 days on PDA. Scale bar: 12a, 12b = 1 cm; 12c–12h = 20 µm; Imaging method: 12a, 12b = DS; 12c = DIC; 12d–12h = BF.

There is evidence for differences in pathogenicity. Whereas V. isaacii strains PD343, PD610–PD613 were not pathogenic on lettuce or artichoke [41], V. klebahnii strain PD401 was pathogenic on lettuce [51]. Verticillium tricorpus is only pathogenic on tomato [23].

Phylogenetic position

Verticillium tricorpus belongs to the group of Verticillium that produces yellow-pigmented hyphae (group Flavexudans). For a phylogenetic tree, see Figure 1 in Inderbitzin et al. (2011).

Host range and geographic distribution

These are inferred from GenBank ITS records, and most likely underestimate the current host range and geographic distribution of V. longisporum. Sugar beet is currently the only known non-Brassicaceae host of V. longisporum confirmed by DNA sequence data.

SubstratesGeographic distribution# plant hosts / # countries
Carnation (Dianthus caryophyllus), Larkspur (Delphinium sp.), Lettuce (Lactuca sativa), Potato (Solanum tuberosum), Soil, Tomato (Solanum lycopersicum) Japan, Netherlands, New Zealand, UK, USA (CA) 5 / 5