Control of Fungi Associated with Cankers of Greenhouse Roses. L. E. Sweets, Assistant Professor, Department of Plant Pathology, Seed and Weed Sciences, Iowa State University, Ames 50011. F. L. Pfleger, Associate Professor, F. C. Morgan, Assistant Extension Specialist, Department of Plant Pathology, University of Minnesota, St. Paul 55108, and J. R. Mizicko, Plant Pathologist, Niagara Seed Operation of Moran Seed, Inc., El Macero, CA 95618. Plant Dis. 66:491-494. Accepted for publication 30 August 1981. 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, 1982. DOI: 10.1094/PD-66-491.

Of six fungi isolated from rose canes, Botryodiplodia theobromae, Botrytis cinerea, Coniothyrium fuckelii, and Trichothecium roseum proved to be pathogenic on the rose cultivars Belinda and Golden Fantasy. Inoculations were made by pinning colonized wheat seed to recently pruned rose canes, wrapping the inoculated canes with a wet paper towel, and covering them with a plastic bag. Alternaria alternata and Pestalotia palmarum were not pathogenic on either cultivar when inoculated using the same procedure. Benomyl, applied as a weekly spray beginning 3 wk after inoculation, reduced canker development caused by Botyrodiplodia theobromae, Botrytis cinerea, C. fuckelii, and T. roseum on Golden Fantasy, whereas on Belinda benomyl was only effective against T. roseum. Chlorothalonil, applied as a weekly spray beginning 3 wk after inoculation, reduced canker development caused by Botrytis cinerea and T. roseum on Golden Fantasy but only reduced canker development caused by T. roseum on Belinda. This is the first report of either Botryodiplodia theobromae or T. roseum on roses.

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