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A Quantitative Method for the Inoculation of Wheat Seedlings with Pycnidiospores of Septoria nodorum. Z. Eyal, Former Postdoctoral Research Fellow, U.S. Department of Agriculture, Agricultural Research Service, Montana State University, Bozeman 59715, Present address of senior author: Department of Botany, Tel-Aviv University, Ramat-Aviv, Israel; A. L. Scharen, Research Plant Pathologist, U.S. Department of Agriculture, Agricultural Research Service, Montana State University, Bozeman 59715. Phytopathology 67:712-714. Accepted for publication 16 November 1976. Copyright © 1977 The American Phytopathological Society, 3340 Pilot Knob Road, St. Paul, MN 55121. All rights reserved.. DOI: 10.1094/Phyto-67-712.

A quantitative inoculation method was developed that permits the evaluation of symptoms produced by pycnidiospores of Septoria nodorum on wheat cultivars in the seedling stage. The following parameters were quantified: number of spores per suspension volume; volume sprayed onto wheat seedlings; and the speed at which plants were revolved during inoculation. The number of spores deposited on glass slides placed among the wheat seedlings gave an estimate of the number of spores deposited on leaf surfaces. The relationships between numbers of spores reaching seedling leaves and symptoms produced (number of lesions and percent necrosis) were evaluated for four spring wheat cultivars. The wheat cultivar, Fortuna, was very susceptible to the disease, whereas Manitou was relatively resistant. The use of our method to detect, measure, and screen for resistance to S. nodorum, and its possible use in genetic studies on the inheritance of resistance is discussed.