Phyllosticta penicillariae on Pearl Millet in the United States. J. P. Wilson, USDA-ARS Forage and Turf Unit, University of Georgia, Coastal Plain Experiment Station, Tifton 31793. G. W. Burton, USDA-ARS Forage and Turf Unit, University of Georgia, Coastal Plain Experiment Station, Tifton 31793. Plant Dis. 74:331. Accepted for publication 5 February 1990. Copyright 1990 The American Phytopathological Society. DOI: 10.1094/PD-74-0331A.
Phyllosticta penicillariae Speg. (1) was isolated from pearl millet
(Pennisetum glaucum (L.) R. Br.) in a breeding nursery at Tifton.
Georgia, in July 1989. Severely infected plants were stunted and
chlorotic, with numerous leaf lesions measuring about 5 X 2.5 mm.
Lesions were generally parallel-sided, with dark brown margins and
light brown necrotic tissue in the center. Coalesced lesions usually
resulted in tattered leaf tissue. Leaf margins were frequently necrotic.
Pycnidia were occasionally observed in necrotic tissue and averaged
75.8 µm in diameter. Conidia were hyaline, single-celled, elliptical
to ovate. and biguttulate and averaged 6.2 X 2.8 µm. Symptoms on
pearl millet in the greenhouse were reproduced 20 days after inoculation
with a conidial suspension followed by incubation in a moist chamber.
The fungus was readily reisolated. To our knowledge, this is the first
report of P. penicillariae in the continental United States.