Disease Note.

First Report of Production of Fumonisin B1 by Fusarium polyphialid-icum Collected from Seeds of Pinus strobus. Hamed K. Abbas, USDA-ARS, Southern Weed Science Lab, Stoneville, MS 38776.. Cynthia M. Ocamb, USDA Forest Service, North Central Forest Experiment Station, St. Paul, MN 55108. Plant Dis. 79:642. Accepted for publication 2 May 1995. Copyright 1995 The American Phytopathological Society. DOI: 10.1094/PD-79-0642B.

Fumonisin B1 (FB1) was first identified in 1988 from Fusarium moniliforme J. Sheld.; five other species were later reported to produce FB1. Fusarium polyphialidicum Marasas, Nelson, Toussoun, & Van Wyk (I), first described in 1986, has never been reported as a plant pathogen. This Fusarium species was isolated from eastern white pine (Pinus stro-bus L.) seeds that were extracted from cones for planting in the field (2). All fourteen isolates of F. polyphialidicum examined were found to produce FB1, when grown on rice. Culture filtrates of these isolates exhibited phytotoxicity to 2-week-old jimsonweed (Datura stramonium L.); symptoms ranged from mild to severe necrosis and mortality. The levels of FB1, produced varied among isolates, from 5.4 to 498 ppm, as determined by high performance liquid chromatography. As levels of FB1, increased, so did symptom severity on jimsonweed. The identity of FB1, was confirmed by thin layer chromatographic and fast atom bombardment mass spectroscopy methods. This is the first report of mycotoxin production by F. polyphialidicum, expanding the range of Fusarium species known to produce FB1.