Effects of Nitrate and Ammonium Nitrogen on Severity of Fusarium Foot and Root Rot and on Yield of Greenhouse Tomatoes. W. R. Jarvis, Head, Agriculture Canada Research Station, Harrow, Ontario N0R 1G0. H. J. Thorpe, Technician, Plant Pathology Section, Agriculture Canada Research Station, Harrow, Ontario N0R 1G0. Plant Dis. 64:309-310. Accepted for publication 29 October 1979. Copyright 1980 American Phytopathological Society. DOI: 10.1094/PD-64-309.

In the presence of adequate lime, nitrate nitrogen and ammonium nitrogen had similar effects on the incidence of Fusarium foot and root rot (Fusarium oxysporum f. sp. radicis-lycopersici) of tomato cultivar MR 13 grown in sterilized reinfested greenhouse soil. The disease differs in this respect from wilt caused by F. oxysporum f. sp. lycopersici.