First Report of Clavicipitaceous Anamorphic Endophytes in Hordeum Species. A. D. Wilson, Plant Germplasm Introduction and Testing Research Unit, USDA-ARS, Washington State University, Pullman 99164. S. L. Clement, W. J. Kaiser, and D. G. Lester. Plant Germplasm Introduction and Testing Research Unit, USDA-ARS, Washington State University, Pullman 99164. Plant Dis. 75:215. Accepted for publication 24 September 1990. Copyright 1991 The American Phytopathological Society. DOI: 10.1094/PD-75-0215D.
Clavicipitaceous endophytes systemically infect many grass species
and produce alkaloids that confer resistance to insects (2) and toxicity
to mammals (1). The mutualistic anamorphic forms (e.g., Acremonium
spp.) do not sporulate or cause symptoms, but they produce distinctive
mycelium in their hosts. The incidence of anamorphic endophytes
in a portion of the U.S. Hordeum germ plasm collection, held at
the National Small Grains Collection in Aberdeen, Idaho, was determined
by microscopic examination of 100 stained seed and seedling
tissues. Endophytes were found in accessions of H. bogdani Wi!.
(47-88%), H. brevisubulatum violaceum (Trin.) Link (68-98%), and
H. comosum Presl (74-92%) at the ranges of seed infection percentages
shown in parentheses. Some endophytes were identified as
Acremonium species. Accessions of H. brachyantherum Nevski, H.
bulbosum L., H. chilense Roem. & Schult., H. jubatum L., H. marinum
Huds., H. murinum L., and H. stenostachys Godr. were endophytefree.
Anamorphic endophytes have not been reported previously in
the wild relatives of cultivated barley (H. vulgare L.) or in genera
of other cereal grasses.