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Phragmidium violaceum (Schultz) G. Winter

Description
Uredinia on lower leaf surface up to 1.5 mm diam., scattered or confluent, dark purple spots up to 4 mm diam. with grey centres form on corresponding upper surface, subepidermal, erumpent, round, up to 1.5 mm, yellow; peripheral paraphyses, clavate, capitate or incurved, hyaline, 35‒55 µm; wall 0.5 µm thick.

Urediniospores globose, subglobose or ellipsoidal, subhyaline to yellow, 20‒28 × 19‒24 µm; wall 2‒4 µm thick, sparsely and distinctly echinulate with spines 2‒4 µm apart.

Teliospores were found in the uredinia, cylindrical, apex rounded, 1‒5 celled, mostly 4 celled, reddish brown, 50‒70 × 28‒32 µm; wall 3‒6 µm thick, verrucose, persistent pedicel, hyaline with walls 2‒4 µm thick.

Hosts
Host family: Rosaceae
Host species: Rubus fruticosus
Rubus procerus

Distribution
QLD, SA, VIC

Comments
Phragmidium violaceum was investigated as a biological control agent for Rubus fruticosus in Australia, but was detected in Victoria before approved for release (Bruzzese & Field 1985).

Highslide JS
Phragmidium violaceum on Rubus fruticosus - BRIP 60123.
Highslide JS
Phragmidium violaceum on Rubus fruticosus - BRIP 60110.
Highslide JS
Phragmidium violaceum on Rubus fruticosus (upper and lower leaf surface) - BRIP 54890.
Scale bar = 1 cm.
Highslide JS
Urediniospores of Phragmidium violaceum on Rubus fruticosus - BRIP 54890.
Scale bar = 10 µm.
Highslide JS
Paraphyses of Phragmidium violaceum on Rubus fruticosus - BRIP 54890.
Scale bar = 10 µm.
Highslide JS
Teliospore of Phragmidium violaceum on Rubus fruticosus - BRIP 60110.
Scale bar = 10 µm.