Phytophthora quercina

Phytophthora quercina is a papillate homothallic soil-borne plant pathogen causing root rot of oak tree species in Europe. It is associated with necrotic fine roots. In culture, this species shows a uniform, dome-shaped and cottonwool-like colony growth pattern. It also frequently presents sympodially branched primary hyphae, a high proportion of elongated, ellipsoid or ovoid oogonia, the absence of amphigynous antheridia. Its sporangia vary greatly in size and shape. Its name derives from Greek Phytophthora ?? ? (phyt n), plant and ??? ? (phthor ), destruction, and quercina stems from the affected genus, Quercus.

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