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Disease Note. Fusarium proliferatum as a Causal Agent in Fusarium Crown and Root Rot of Asparagus. W. H. Elmer, Department of Plant Pathology and Ecology, The Connecticut Agricultural Experiment Station, Box 1106, New Haven 06504. . Plant Dis. 74:938. Accepted for publication 16 July 1990. Copyright 1990 The American Phytopathological Society. DOI: 10.1094/PD-74-0938E. Fusarium proliferatum (T. Matsushima) Nirenberg was isolated
from chlorotic and wilted asparagus (Asparagus officinalis L.) ferns
in fields in Connecticut during the summers of 1987, 1988, and 1989.
Less than 7% of 150 isolates were F. proliferatum. F. proliferatum
has been taxonomically separated from F. moniliforme J. Sheld. (1),
a known pathogen of asparagus; the pathogenicity of F. proliferatum
to asparagus was unknown. Koch's postulates were completed in two
separate trials in which transplants of cv. Mary Washington were
placed in steamed soil infested with sterile fescue seed or with fescue
seed colonized by F. proliferatum or F. moniliforme. After 10 wk,
disease ratings (0-12), based on percentage of discolored stems, crowns,
and roots, were significantly greater for plants grown in soil infested
with F. proliferatum or with F. moniliforme than for uninoculated
plants. Compared with uninoculated plants, plants grown in soil
infested with F. proliferatum or F. moniliforme were reduced in weight
by an average 41 or 30%, respectively. F. proliferatum should be
considered as a causal agent in Fusarium crown and root rot of
asparagus. |