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New Diseases and Epidemics Fusarium Root Rot of Douglas-Fir and Fraser Fir Seedlings in Pennsylvania. W. Merrill, Professor, Department of Plant Pathology, Pennsylvania State University, University Park 16802. K. McCall, Undergraduate Student, and L. Zang, Research Assistant, Department of Plant Pathology, Pennsylvania State University, University Park 16802. Plant Dis. 65:913-914. Accepted for publication 16 March 1981. Copyright 1981 American Phytopathological Society. DOI: 10.1094/PD-65-913. Root rot of Douglas-fir and Fraser fir seedlings caused by Fusarium solani and of Douglas-fir seedlings caused by F. oxysporum is reported from Pennsylvania. During their second growing season, Douglas-fir nursery seedlings became stunted and chlorotic, wilted, and died. Mortality was about 50% in four nurseries; another 25–50% of the remaining seedlings were stunted, had poorly developed root systems, and probably would not have survived outplanting. In one nursery, more than 90% of the Douglas-fir seedlings died late in their first growing season. In a single seedbed of Fraser fir next to a severely affected Douglas-fir seedbed, 15% of the second year seedlings died; F. solani was recovered from roots with cortical root rot.
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