Effects of Triadimefon and Triadimenol as Seed Dressings on Incidence of Fusiform Rust on Loblolly Pine Seedlings. W. D. Kelley, Associate Professor, Department of Botany, Plant Pathology, and Microbiology, Auburn University, Auburn 36849. J. C. Williams, Professor, Research Data Analysis, Alabama Agricultural Experiment Station, Auburn University, Auburn 36849. Plant Dis. 69:147-148. Accepted for publication 31 July 1984. Copyright 1985 The American Phytopathological Society. DOI: 10.1094/PD-69-147.

Triadimefon or triadimenol applied as seed dressings at rates of 0.31, 0.62, and 1.25 g a.i./kg of seed protected emerging seedlings of Pinus taeda from rust caused by Cronartium quercuum f. sp. fusiforme. Triadimefon was superior to triadimenol. The degree of protection for each compound decreased as seedling age increased. Both compounds were compatible with the animal repellent and fungicide thiram. Triadimefon applied as a seed dressing at a rate of 1.25 g a.i./kg of seed provided protection equal to that of the triadimefon seed soak (800 mg of triadimefon per liter, 24-hr seed soak) currently being used by forest tree nursery personnel; both methods provided adequate protection to emerging seedlings for at least 36 days after sowing.