Abstract
The sponge matrix method for obtaining synchronous spores of fungi was applied to the evaluation of sporulation inhibitors as fungicides. Inhibitory activity of a chemical against the sporulation of Piricularia oryzae was studied with simple procedures and estimation and the results obtained by this method allowed kinetic analyses. The relation between the dosage (I) and immersion time(t) required to inhibit 50 per cent of the sporulation was expressed fairly well by the equation (I)nt=C, where n and C are constants. The comparison of the results of this method with those of in vivo methods suggested that the inhibition activity of a chemical for practical use was estimated fairly acculately by the sponge matrix test with variation in the immersion time.
