Small amounts of copper ions induce the release from spores ofGlomerella cingulataSpauld. & Schrenk. of increased amounts of amino acids, predominantly glutamic acid, α-alanine, γ-aminobutyric acid, aspartic acid, glycine, leucine(s), and serine. Sodium dimethyldithiocarbamate, and copper in the form of the dimethyldithiocarbamate complex, do not show this effect. Added protein, such as egg albumin or cellulase, or the extracellular protein of spores suspended in water, forms a soluble ternary complex with dithiocarbamate and copper ions. This results in little or no loss of dithiocarbamate from solution and in reduced toxicity in the first mode of the dosage–response curve.