Dimethomorph is a morpholine fungicide that inhibits fungal cell wall formation.¹It inhibits mycelial growth of the oomycete fungiP. citrophthora,P. parasitica,P. capsici, andP. infestans(EC₅₀s = 0.14, 0.38,<0.1, and 0.16-0.3 µg/ml, respectively) but is less active against the green algae speciesC. vulgarisorS. obliquus in vitro(EC₅₀s = 47.46 and 44.87 µg/ml, respectively).^2,3,4It inhibits androgen receptor (AR) activity in a reporter assay in MDA-kb2 human breast cancer cells but not in a yeast antiandrogen screen (IC₂₀s = 0.263 and 38.5 µM, respectively).⁵It is not toxic to rats (LD₅₀= 3,900 mg/kg) or goldfish (C. auratus; LC₅₀= >32 µg/ml).^4,1

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