Comparative Control of Sclerotium rolfsii on Golf Greens in Northern California with Fungicides, Inorganic Salts, and Trichoderma spp.. Z. K. Punja, Graduate Research Assistant, Department of Plant Pathology, University of California, Davis 95616. R. G. Grogan, Professor, Department of Plant Pathology, University of California, Davis 95616, and T. Unruh, Golf Course Superintendent, Del Paso Country Club, Sacramento, CA 95821. Plant Dis. 66:1125-1128. Accepted for publication 17 March 1982. Copyright 1982 American Phytopathological Society. DOI: 10.1094/PD-66-1125.

Sclerotium rolfsii blight on bentgrass-annual bluegrass golf greens in Sacramento, CA, was controlled with 2,6-dichloro-4-nitroaniline with cycloheximide, carboxin, and PCNB with fertilizer applied at 14-day intervals over a 4-mo period starting 1 May 1981. Captan and furmecyclox (OAC 3890) also significantly reduced disease severity. Carboxin applied at reduced rates in combination with reduced amounts of either captan or ammonium bicarbonate provided better disease control than carboxin or captan applied alone at higher rates. Applications of calcium nitrate or hydrated lime did not give satisfactory control of disease. Similarly, applications in 1979 and 1980 of Trichoderma inoculum grown on diatomaceous earth granules impregnated with a 10% molasses solution did not reduce disease severity in either year, although there was a significant increase in the level of Trichoderma in treated plots in comparison with control plots.

Keyword(s): bicarbonate, biocontrol, chemical control, southern blight.