Evaluation of Several Fungicides and Adjuvant Materials for Control of Brown Spot of Wild Rice. J. A. Percich, Assistant Professor, Department of Plant Pathology, University of Minnesota, St. Paul 55108. L. J. Nickelson, Former Research Specialist, Department of Plant Pathology, University of Minnesota, St. Paul 55108. Plant Dis. 66:1001-1003. Accepted for publication 16 February 1982. Copyright 1982 American Phytopathological Society. DOI: 10.1094/PD-66-1001.

Several fungicides separately and mancozeb in combination with each of five different adjuvant materials were field-tested for effectiveness in reducing brown spot of wild rice (Zizania aquatica) caused by Drechslera oryzae (Bipolaris oryzae) and D. sorokiniana (B. sorokiniana). The fungicides were applied on wild rice plants at 14-day intervals from early flowering until 26 days before harvest. The following fungicides significantly (P = 0.05) controlled brown spot (114 L of spray per hectare): benomyl 50WP at 1.1 kg/ha; chlorothalonil 6F at 2.9 kg/ha; mancozeb at 2.3 kg/ha; fenapanil (RH-2161) 50WP at 0.6 kg/ha; and iprodione (RP 26019) 50 flowable at 6.4 kg/ha. Two or three applications of mancozeb with Pinolene (Nu-Film) at 0.6 ml/L or Acrylocoat at 1.2 ml/L resulted in significantly better control than the recommended four applications of mancozeb with Triton CS-7 at 1.2 ml/L.

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