Crops > Ornamentals > Polyscias spp. > Pseudocercospora panacis, Polyscias, Pacific

Pseudocercospora panacis

September 2005. A request from the Secretariat of the Pacific Community for the identification of Polyscias species bearing infections from Pseudocercospora panacis. Apparently, there are two cultivars or varieties of P guilfoylei: P guilfoylei var. lanciniata and P guilfoylei var. guilfoylei.

Thee was a lot of discussion among the members:

There is a good key with descriptions and line drawings in the new A Tropical Garden Flora by Staples et al. See also images at links: http://www.hear.org/starr/hiplants/images/thumbnails/html/polyscias_scutellaria.htm
http://www.hear.org/starr/hiplants/images/thumbnails/html/polyscias_guilfoylei.htm

A suggestion from Art Whistler was:

• Photo (left) P scutellaria ‘Tricochleata’. This variety has yellowish-green leaflets that are roughly divided into three, toothed lobes. It is common in American Samoa, as are the Pseudocercospora leaf spots. The leaves of P scutellaria are noticeably larger, entire,and lightly scalloped, but not toothed.

• Photo (right) This is closest to P guilfoylei, it has, “. . . toothed and typically white leaf margins”. Maybe the key word is “typically”. The leaf description is: odd-pinnately compound or the leaflets further irregularly divided, alternate, leaflets 5 to 9, blades elliptic to oblong, 4-18 cm long, margins often white and toothed to deeply lobed. The leaves in his photo are a darker green than in your photo, but this could be a difference in light exposure.

Cook Islands stated that Polyscias scutellaria and P guilfoylei are confusing and confused. In addition to AC Smith’s Flora Vitiensis Nova, a good place to start is: Lowry PP (1989) A revision of Araliaceae from Vanuata. Bull. Mus. natn. Hist. nat. Paris, 4th series 11 (section B, No.2): 117-155. The interpreation was:

Polyscias guilfoylei (left) is Polyscias scutellaria cv. Tricochleata or ‘Tricochleata’. ‘Tricochleata’ is the left one in the image at: http://cookislands.bishopmuseum.org/species.asp?id=6565

Polyscias guilfoylei (right) is the regular Polyscias guilfoylei. The latter species with form ‘Laciniata’ and ‘Crispa’ are shown at: http://cookislands.bishopmuseum.org/species.asp?id=6564