A Method for Monitoring the Sensitivity of Botrytis cinerea to Mepanipyrim

Abstract

Mepanipyrim is an anilinopyrimidine fungicide with a broad spectrum of activities. Mepanipyrim did not inhibit mycelial growth of Botrytis cinerea completely on complex media and therefore, this method is considered not to be useful for evaluation of the sensitivity of isolated B. cinerea to mepanipyrim. As a result of our studies, we have established new techniques to determine the fungal sensitivity to mepanipyrim in vitro by utilizing the inhibitory activity of mepanipyrim against protein secretion and germ-tube elongation. The FGA-paper disc method is considered to be more useful and more reliable for evaluation of the sensitivity of B. cinerea to mepanipyrim.

Biochemical basis of selective disease controlling activity of mepanipyrim

“…4) While mepanipyrim markedly affects the infection process of B. cinerea at 1-10 mg/ml, especially germ tube elongation, secondary appressorium formation and penetration, it hardly inhibited spore germination and did not fully inhibit the mycelial growth of B. cinerea. 1,3) Taking advantage of its strong inhibition against germ tube elongation instead of weakly mycelial growth inhibition, the FGA-paper disc method 5) can evaluate the sensitivity of B. cinerea to mepanipyrim. In addition, assay qualities of the FGA-paper disc method were improved to use gelatin in the medium, resulting in utilizing the inhibitory activity of mepanipyrim in protease secretion.…”