VIEW ARTICLE

Research

Survival of Common and Dwarf Bunt Teliospores and Intact Sori After Fumigation of High and Low Moisture Content Winter Wheat. J. L. Smilanick, Agricultural Research Service, U.S. Department of Agriculture, Horticultural Crops Research Laboratory, 2021 South Peach Avenue, Fresno, CA 93727. P. L. Hartsell, R. Denis-Arrue, D. J. Henson, J. D. McKinney, J. C. Tebbets, and B. J. Goates. Agricultural Research Service, U.S. Department of Agriculture, Horticultural Crops Research Laboratory, 2021 South Peach Avenue, Fresno, CA 93727; and Agricultural Research Service, U.S. Department of Agriculture, National Small Grains Germplasm Research Facility, Aberdeen, ID 83210. Plant Dis. 76:293-296. Accepted for publication 23 October 1991. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1992. DOI: 10.1094/PD-76-0293.

Teliospores and sori of Tilletia tritici and T. controversa were mixed with wheat seed (cvs. Daws and Itana) and fumigated with methyl bromide. The fumigant was applied one to four times at atmospheric pressure or under vacuum. After fumigation, teliospore germination and wheat seed germination were determined. Applications of methyl bromide (240 g/m³ for 24 hr) at atmospheric pressure repeated four times prevented teliospore germination of T. controversa in low moisture content wheat seed (10.2% moisture). Sori did not influence the sensitivity of teliospores to methyl bromide. Teliospores infesting moist wheat (14.7% moisture) were about six times more sensitive to methyl bromide fumigation than those in low moisture content wheat seed (10.2–12.4% moisture). T. tritici was more sensitive to all of the fumigants than was T. controversa. Fumigant doses that reduced teliospore germination were high and caused a marked reduction in wheat seed germination.