Abstract
LONDON. Association of Economic Biologists, October 14.— Sir David Prain, president, in the chair.— Dr. W. Brown: The physiology of the infection process. The lecturer gave an account of recent work carried out in the Imperial College of Science on the physiology of parasitism, dealing chiefly with the fungus Botrytis cinerea. Evidence was brought forward showing that the actual penetration of the hosttissue took place by mechanical means. The most careful examination, both by chemical and cytological methods, failed to show evidence of a cutindissolving enzyme. The mechanical theory of penetration was further supported by the fact that fungi could penetrate membranes, such as gold-leaf, paraffin-wax, etc., on which they could not possibly exert any chemical action whatsoever. The well-known “action in advance” subsequent to penetration was shown to be due to a toxic enzyme, the properties of which had been studied in detail. Previous to penetration the fungus exerted no action on the host. On the other hand, a passive exosmosis of substances took place from the host into the infection drop, this leading in some cases to stimulation, in others to inhibition, of fungal germination. The question of the existence of tropic stimuli as a factor in infection was discussed, and attention was directed to the necessity of investigating the nutritional requirements of particular fungi, in connection with which numerous problems had arisen in recent work.
Article PDF
Rights and permissions
About this article
Cite this article
Societies and Academies. Nature 108, 325–326 (1921). https://doi.org/10.1038/108325a0
Issue Date:
DOI: https://doi.org/10.1038/108325a0