Effect of Insecticide Treatment of Compost and Casing on Mushroom Yield

Bendiocarb, carbosulfan, cyromazine, penfluron, Sumitomo 31183, and Sumitomo 4496 have proven efficacious for controlling a sciarid fly, Lycoriella mali (Fitch) (Diptera: Sciaridae), the principal insect pest of commercial mushrooms in North America. In this study, these compounds were evaluated for potential phytotoxicity to the mushroom Agaricus bisporus (Lange). Growth rate of the mycelium through the compost and through the casing; the weight, number, and size of mushrooms produced; and the time of each growth flush were measured. Penfluron was the only material that did not cause some yield reduction. Cyromazine and the low dosage of carbosulfan caused minor reductions in yield.