Effects of several fungicides on the nitrogen components contained in mycelia of Piricularia oryzae Cav

Abstract

1) The present paper deals with the results of experiments on the effects of several fungicides on the nitrogen components contained in mycelia of Piricularia oryzae. The fungicides used in this experiments were as follows: copper shlfate, mercuric chloride, phenyl mercuric dinaphthylmethane disulfonate (PMF), n-trichloromethyl thiotetrahydrophthalimid (Captan), 2, 3-dichloro-1, 4-naphthoquinone (Dichlone), tetramethyl thiuramdisulfide (TMTD), ferric dimethyl dithiocarbamate (Fermate), zinc dimethyl dithiocarbamate (Zerlate) and Blasticidine-S.2) The electrophoretic proteins contained in mycelia of P. oryzae decreased, when the mycelia were contacted with 10-4∼10-3 molar solution of copper sulfate, mercuric chloride or PMF for 16 hours, and the proteins did not decreased when the mycelia were contacted with the solution of Captan or six other fungicides for 16 hours, but the proteins decreased when the mycelia were contacted with the solution for 24 hours or more.3) Total-nitrogen content contained in mycelia of P. oryzae when the mycelia were contacted with the solution of mercuric chloride, copper sulfate, Captan, Dichlone, TMTD and Blasticidine-S, and the decrease were different in degree with these fungicides.Protein-nitrogen content in mycelia decreased, too, and the decrease were nearly same in degree, This result was not agreed with the result on electrophoretic proteins.4) When the mycelia were contacted with 10-4∼10-3 molar solution of heavy metalic fungicides for 16 hours, the free amino acids contained in mycelia were found to be generally decreased in concentration, but, when the mycelia were contacted with 100γ/ml solution of Blasticidin-S for 48 hours or more, an unidentified ninhydrin-reacting spot near Leucine was noted.