Occurrence and Pathogenicity of Verticicladiella procera in Christmas Tree Plantations in Virginia. A. L. Lackner, Graduate Research Assistant, Department of Plant Pathology and Physiology, Virginia Polytechnic Institute and State University, Blacksburg 24061. S. A. Alexander, Assistant Professor, Department of Plant Pathology and Physiology, Virginia Polytechnic Institute and State University, Blacksburg 24061. Plant Dis. 66:211-212. Accepted for publication 20 May 1981. Copyright 1982 American Phytopathological Society. DOI: 10.1094/PD-66-211.

Verticicladiella procera was identified as the cause of severe losses in some Christmas tree plantations in Virginia. Losses for 1980 totaled about 700 marketable trees in eight plantations. V. procera was isolated from Pinus strobus, P. sylvestris, and P. nigra. Pathogenicity was determined by inoculating 2-yr-old P. strobus seedlings with V. procera. Inoculation was accomplished by dipping root systems in a spore suspension or by inserting small blocks of white pine stem wood colonized with V. procera into a slit wound in the taproot. Inoculated seedlings began dying in 2 wk and continued to die over a 10-wk period. V. procera was isolated from 50% of the seedlings inoculated by root-dip and from 25% of the seedlings inoculated by colonized blocks. V. procera was isolated only from dead, inoculated seedlings.

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