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 Add this item to the list  824218 Original description
Remarks (public):Phytophthora oleae morphologically resembles other species in the ‘P. citricola complex’, however it can be clearly separated from species of this complex and from all other known Phytophthora species on the basis of sequences of ITS and cox1 sequences. 
Description type:Original description 
Description:Colonies with a stellate to radial growth pattern on PDA, rosaceous on CA and abundant aerial mycelium with no definite pattern on V8A. On MA 2%, young colonies with no definite pattern, aged colonies with a slight stellate pattern. Cardinal temperatures (minimum, maximum and optimum) for radial growth 10, 25 and 20ºC, respectively. Mean radial growth rate on V8A at 20ºC 4.1±0.3 mm·day-1. No growth at 30 and 35ºC. Primary hyphae on V8A 3-8 µm wide (average 5.4 µm) and no sympodial branching. Both catenulate and simple, intercalary hyphal swellings, sporadically observed. Sporangia ovoid, abundant in water culture, less numerous on solid agar, borne in lax, simple sympodial branching, sometime sessile, persistent, semipapillate, occasionally bipapillate. Dimensions of sporangia (µm) 32-58 x 22-36 (mean 44.7±6.3 x 30.0±3.5) with a length/breadth (l/b) ratio of 1.5. Chlamydospores very sporadic and were only observed on solid media. Phytophthora oleae is homothallic. Sexual reproductive structures were produced in single culture on V8A after one week. Oogonia, prevalently terminal, globose to sub-globose, smooth-walled, with diameter (µm) ranging between 24 and 30 (mean 27.4±1.8). Oospores spherical and plerotic, with mean diameter (µm) 24.7±1.6 (range22-28) and thick wall (mean thickness 2.5±0.2). Antheridia always paragynous, single, terminal, club-shaped and rarely with a finger-like appendix. Their dimensions (µm) were 11.3±1.3 x 7.6±0.9. 
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