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Description type:Original description 
Description:Anamorph: Cylindrocarpon liriodendri J.D. MacDon. & E.E. Butler, Plant Disease 65: 156. 1981.
Perithecia formed heterothallically in vitro, disposed solitarily or in groups of up to six, developing directly on the agar surface or on sterile pieces of beach wood or pine needles, ovoid to obpyriform, with a flattened apex, up to 70 µm wide, orange to red, becoming purple-red in 3 % KOH (positive colour reaction), smooth to warted, up to 300 µm diam and high; with minute stroma of dark red pseudoparenchymatal cells; perithecial wall consisting of two regions; outer region 15-30 µm thick, composed of 1-3 layers of angular to subglobose cells, 10-25 ´ 8-17 µm; cell walls up to 1 µm thick; inner region 10-15 µm thick, composed of cells that are flat in transverse optical section and angular to oval in subsurface optical face view, 7-15 ´ 3-5 µm; perithecial warts consisting of globose to subglobose cells, 15-30 ´ 15-20 µm in surface view. Asci narrowly clavate to cylindrical, 45-60 ´ 5-6 µm, 8-spored; apex subtruncate, with a minutely visible ring. Ascospores medianly 1-septate, ellipsoidal to oblong ellipsoidal, somewhat tapering towards both ends, smooth to finely warted, (7-)9-11(-14) ´ (2.5-)3-3.5(-4) µm.
Conidiophores simple or complex, sporodochial. Simple conidiophores arising laterally or terminally from the aerial mycelium or erect, arising from the agar surface, solitary to loosely aggregated, unbranched or sparsely branched, 1-6-septate, rarely consisting only of the phialide, 40-160 ?m long; phialides monophialidic, cylindrical, 20-40 ´ 3-4 µm, 2-2.5 ?m near aperture. Sporodochial conidiophores aggregated in pionnote sporodochia, irregularly branched; phialides cylindrical, mostly widest near the base, 15-30 ´ 2.5-3.5 µm, 2-2.5 ?m wide near the aperture. Micro- and macroconidia present on both types of conidiophores. Macroconidia predominating, formed by both types of conidiophores, predominantly (1-)3-septate, straight or sometimes slightly curved, cylindrical, mostly with a visible, basal or slightly laterally displaced hilum; 3-septate macroconidia, (24-)35-40(-55) ´ (4.5-)5.5-6(-6.5) ?m (n = 116). Microconidia sparsely produced on all media, 0-1-septate, ellipsoidal to subcylindrical to ovoid, more or less straight, with a minutely or clearly lateral hilum; aseptate subcylindrical to ellipsoidal microconidia, 5-15 ´ 2.5-4 ?m; aseptate ovoid microconidia, 3-5 ´ 3-4 µm, formed predominently on dense, penicillately branched conidiophores on CLA and twigs, and then also without subcylindrical to ellipsoidal microconidia, which again occur on other media as a mixture with ovoid microconidia. Conidia formed in heads on simple conidiophores, as hyaline masses on simple as well as complex conidiophores. Chlamydospores common, mostly in short, intercalary chains, 10-20 ´ 10-17 µm.
Specimens examined: Heterothallic mating between two opposite mating types. France, Vitis vinifera, P. Larignon, CBS 112591 ´ South Africa, F. Halleen, Vitis vinifera, CBS 112596, holotype specimen herb. CBS 17776; Portugal, Vitis vinifera, C. Rego, CBS 117526 ´ Portugal, C. Rego, Vitis vinifera, CBS 117527, herb. CBS 17781; Portugal, Vitis vinifera, C. Rego, CBS 117527 ´ California, U.S.A., Liriodendron tulipifera, CBS 110.81, herb. CBS 17780; Portugal, Vitis vinifera, C. Rego, CBS 117527 ´ South Africa, F. Halleen, Vitis vinifera, CBS 112596, herb. CBS 17779; Portugal, Vitis vinifera, C. Rego, CBS 117527 ´ South Africa, F. Halleen, Vitis vinifera, CBS 112602, herb. CBS 17778; Portugal, Vitis vinifera, C. Rego, CBS 117527 ´ France, P. Larignon, Vitis vinifera, CBS 112610, herb. CBS 17777.
Mating studies: Perithecia observed within 3-4 wk in crossings of strains: CBS 117526 ´ CBS 117527; CBS 117527 ´ CBS 110.81 (ex-type of C. liriodendri); CBS 117527 ´ CBS 112602; CBS 117527 ´ CBS 112610; CBS 117527 ´ CBS 112596; CBS 112591 ´ CBS 112596.
Cultural characteristics: Colonies on PDA (surface and reverse) cinnamon to sepia, with sparse aerial mycelium. On OA dark brick to fawn (surface and reverse). Minimum temperature for growth < 4 °C; optimum temperature 20-25 °C, at which PDA colonies reach 30-42 mm diam after 7 d in the dark; maximum temperature between 30-35 °C.
Host range and distribution: Vitis vinifera (France, Portugal, New Zealand, South Africa), The Netherlands (Cyclamen sp.), Liriodendron tulipifera (U.S.A., California).
Habitat: Roots and rootstocks of grapevines, causing black foot disease. The ex-type culture was described from Liriodendron tulipifera in California, while another was associated with bulb rot of a Cyclamen sp. in the Netherlands, so it is possible that this pathogen has a much wider host range than that reported here.
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