Fungicidal Control of Infection by Penicillium spp. of Precooled Tulip Bulbs in a Modified Atmosphere Package. T. A. Prince, Former Graduate Research Assistant, Department of Horticulture, Michigan State University, East Lansing 48824. R. C. Herner, and C. T. Stephens. Professor, Department of Horticulture, and Associate Professor, Department of Botany and Plant Pathology, Michigan State University, East Lansing 48824. Plant Dis. 71:307-311. Accepted for publication 29 July 1986. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/PD-71-0307.

Basal plates of precooled tulip bulbs maintained in sealed modified atmosphere (MA) packages of low-density polyethylene film for 3 or 4 wk became infected with species of Penicillium. High levels of infection in the basal plates were correlated with increased ethylene levels in the packages and increased floral abortion during subsequent forcing of the bulbs. Prochloraz and etaconazole dip pretreatment of the bulbs and captan dust application before packaging reduced the occurrence of basal plate rot caused by Penicillium spp. and allowed excellent root growth and flowering of the bulbs. Benomyl, captan, and chlorine dip pretreatments provided poor control of basal plate infection in the packages.