Effect of Mepanipyrim on Uptake of Various Substrates and Macromolecular Biosyntheses in Botrytis cinerea

Abstract

Mepanipyrim, N-(4-methyl-6-prop-l-ynylpyrimidin-2-yl)aniline, hardly inhibited the mycelial respiration and the syntheses of DNA, RNA, protein, lipids and cell walls in mycelia of Botrytis cinerea at 100 μg/ml. By the treatment of mepanipyrim at 10-100μg/ml, each uptake of 14C-labeled glucose, acetate, uridine, thymidine, alanine or glucosamine by the mycelia of B. cinerea was inhibited, but no apparent uptake inhibition of these precursors was observed below 1 μg/ml. The inhibition by mepanipyrim of the active transport process across the cellular membrane may bring about a chronic deficiency in most intracellular substrates essential for growth and development. However, the effect of mepanipyrim appeared not to be strong enough to disrupt the overall functions of cell membrane in B. cinerea; because it neither stimulated the leakage of protein, phosphate, glucose and electrolytes from the cells, nor influenced the bursting rate of protoplasts by osmotic shock. © 1994, Pesticide Science Society of Japan. All rights reserved.