VIEW ARTICLE

Disease Control and Pest Management

Influence of Fungicide Sprays on Sporulation of Cochliobolus sativus on Cypress Wheat and on Conidial Populations in Soil. S. H. F. Chinn, Research Scientist, Research Station, Research Branch, Agriculture Canada, 107 Science Crescent, Saskatoon, Saskatchewan S7N 0X2, Canada; Phytopathology 67:133-138. Accepted for publication 5 August 1976. Copyright © 1977 The American Phytopathological Society, 3340 Pilot Knob Road, St. Paul, MN 55121. All rights reserved.. DOI: 10.1094/Phyto-67-133.

Seven fungicides were sprayed on the basal stems of wheat (cultivar Cypress) in field experiments at Saskatoon and Scott, Saskatchewan. Duter, LFA 2043, and Panogen 15 were the most effective in reducing sporulation of Cochliobolus sativus on the stems. None of the fungicides influenced sporulation on the subcrown internodes. Results were similar whether the fungicides were applied in mid-July, late July, or early August. At Saskatoon, the sporulation indices on the basal stems following sprays with Duter and water were 1.8 and 4.6, respectively, and conidial numbers per gram of soil were 996 and 4,045, respectively. Of the seven fungicides, Duter influenced the viability of the conidia most adversely. Sporulation indices on basal stems and conidial populations in soil were much higher at Saskatoon than at Scott. The potential of fungicide sprays to control common root rot of wheat by reducing sporulation of the pathogen is discussed.