VIEW ARTICLE

Disease Control and Pest Management

Seed Treatment with L-Sorbose to Control Damping-Off or Cotton Seedlings by Rhizoctonia solani. C. R. Howell, Research Plant Pathologist, Agricultural Research Service, U.S. Department of Agriculture, National Cotton Pathology Research Laboratory, P.O. Drawer JF, College Station, TX 77840; Phytopathology 68:1096-1098. Accepted for publication 31 January 1978. Copyright © 1978 The American Phytopathological Society, 3340 Pilot Knob Road, St. Paul, MN 55121. All rights reserved.. DOI: 10.1094/Phyto-68-1096.

The keto sugar, L-sorbose, inhibits hyphal extension and promotes profuse branching in Rhizoctonia solani. When applied to cotton seed planted in soil infested with the pathogen, L-sorbose protected the seed against damping-off. It is fungistatic and not fungicidal. Because L-sorbose is metabolized by soil microorganisms, it does not persist or accumulate in the soil. When applied to seed in crystalline form with sticker, L-sorbose is highly water soluble and may be leached from the spermosphere. Use of a less soluble formulation consisting of L-sorbose mixed with cellulose acetate in acetone alleviated this problem.