Membrane Functions and Tolerance to Aromatic Hydrocarbon Fungitoxicants in Conidia of Fusarium solani

Abstract

AbstractWith the use of 32P‐labeled phosphate and 42K2CO3 the effect of diphenyl on permeability and uptake properties of the cytoplasmic membrane in wild type and diphenyl‐tolerant mutant conidia of Fusarium solani f. cucurbitae was studied. No general damage to the membrane with unspecific leakage of cell constituents was demonstrated under conditions in which diphenyl prevents germination of wild type conidia.The fresh conidia do not require exogenous supply of energy for the uptake of phosphate or of potassium. In the wild type the entry of 32P is inhibited but that of 42K strikingly stimulated by diphenyl. Independently of the tolerant mutant gene present, the mutant conidia are significantly less sensitive to the phosphate uptake inhibition and not affected at all by diphenyl with respect to the uptake of potassium. The latter difference from the wild type seems to indicate genetic control of some property of the potassium transport system in this fungus.