BIOLOGICAL-ACTIVITY OF CARPROPAMID (KTU-3616) - A NEW FUNGICIDE FOR RICE BLAST DISEASE

Carpropamid ,2-dichloro-N-[1-(4-chlorophenyl)ethyl]-1-ethyl-3- methylc yclopropane-carboxamide}) was found to be an effective rice blast fung icide with systemic properties. The basic activities of the compound w ere studied in vitro and in vivo. The compound did not inhibit mycelia l growth of various plant pathogenic fungi tested except Oomycetes spp . In addition, carpropamid did not show direct activity on the mycelia l growth, the spore germination and the appressorium formation of rice blast fungus. Inhibition of fungal melanin biosynthesis was observed, however, in the mycelial growth test with many fungi and in appressor ium cells of rice blast fungus. The compound showed strong penetration inhibition into rice epidermal cells at very low concentrations but w as less effective once the appressorial penetration had started.