The Effects of Pathogen Numbers and Tillage on Root Disease Severity, Root Length, and Seed Yields in Green Peas. J. M. Kraft, Supervisory Research Plant Pathologist, Vegetable and Forage Crops Production, Agricultural Research Service, U.S. Department of Agriculture, Prosser, WA 99350. D. E. Wilkins, Agricultural Engineer, Agricultural Research Service, U.S. Department of Agriculture, Pendleton, OR 97801. Plant Dis. 73:884-887. Accepted for publication 31 May 1989. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1989. DOI: 10.1094/PD-73-0884.

A 2-yr field study was conducted to determine the effects of soil compaction and inoculum levels of Fusarium solani f. sp. pisi on pea (Pisum sativum) root length, disease severity, plant biomass, and dry seed yields. Soil inoculum levels of F. s. f. sp. pisi were significantly reduced by fumigation with methyl bromide at the 0–20 cm depth but were not reduced below 20 cm. Use of a paraplow treatment to reduce compaction increased root density over that obtained with the conventional moldboard plow treatment. The combination of fumigation and paraplow tillage decreased root disease severity and increased root length, biomass, and dry seed yields.

Keyword(s): Fusarium root rot.