Volume 17 Part 1 Article 38
Title: Management of Casing Trichoderma Using Fungicides
Authors: D. Lee Rinker and G. Alm
Trichoderma species are present in the casing material and can cause cap spotting which lowers mushroom quality and reduces marketable sales. One method to lower the incidence of Trichoderma species in the casing is to use fungicides. Ten isolates, representing eight species of Trichoderma, were evaluated on malt agar with benomyl, chlorothalonil, thiabendazole and thiophanate methyl at concentrations ranging from 0 to 200 ppm. Thiabendazole was the most effective, followed by benomyl and thiophanate methyl. Chlorothalonil was ineffective. The same compounds were evaluated in mushroom crops. Comparison of the four fungicides indicated that chlorothalonil was ineffective against Trichoderma in the casing and that the three benzimidazoles were similar in effectiveness. Adjustment of casing pH is yet another approach to Trichoderma management. In agar, high pH reduced spore germination and retarded linear growth. Mushroom yields when casing was artificially inoculated with three Trichoderma species were negatively affected by T. koningii and T. harzianum but not T. atroviride, despite adjustments of casing pH to either 7 or 9. Some fungicides can lower the incidence of Trichoderma species in the casing, providing a management tool for mushroom growers.Please login to download the PDF for this proceeding.