Plant Pathology (2014) 63, 1095-1109

B. Henricot, A. Pérez Sierra and T. Jung (2014)
Phytophthora pachypleura sp. nov., a new species causing root rot of Aucuba japonica and other ornamentals in the United Kingdom
Plant Pathology 63 (5), 1095-1109
Abstract: Isolates of an unknown Phytophthora species from the ' Phytophthora citricola complex' have been found associated with mortality of Aucuba japonica in the UK. Based on morphological characteristics, growth–temperature relationships, sequences of five DNA regions and pathogenicity assays, the proposed novel species is described as Phytophthora pachypleura. Being homothallic with paragynous antheridia and semipapillate sporangia, P. pachypleura resembles other species in the ' P. citricola complex' but can be discriminated by its distinctively thick-walled oospores with an oospore wall index of 0·71. In the phylogenetic analysis based on three nuclear (ITS, ß-tubulin, EF-1alpha) and two mitochondrial (cox1, nadh1) DNA regions, P. pachypleura formed a distinct clade within the ' P. citricola complex' with P. citricola s. str., P. citricola E and P. acerina as its closest relatives. Phytophthora pachypleura is more aggressive to A. japonica than P. plurivora and P. multivora and has the potential to affect other ornamental species.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Béatrice Henricot, Thomas Jung

Research topic(s) for pests/diseases/weeds:
identification/taxonomy

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Phytophthora pachypleura	Aucuba (crop)	United Kingdom