Effects of Host-Specific Toxins on Electropotentials of Plant Cells 123

Host-specific toxins from Helminthosporium victoriae (HV) and Periconia circinata (PC) caused gradual decreases in the negative electropotentials of single cells of susceptible but not of resistant plants. When tissues were held in a standard nutrient solution, the decrease (depolarization) induced...

Full description

Saved in:
Bibliographic Details
Published in:Plant physiology (Bethesda) 1974-09, Vol.54 (3), p.246-249
Main Authors: Gardner, John M., Scheffer, Robert P., Higinbotham, Noe
Format: Article
Language:English
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Host-specific toxins from Helminthosporium victoriae (HV) and Periconia circinata (PC) caused gradual decreases in the negative electropotentials of single cells of susceptible but not of resistant plants. When tissues were held in a standard nutrient solution, the decrease (depolarization) induced by HV toxin was approximately 50 mv/hr; the decrease induced by PC toxin was even more gradual. Changes in ion efflux were detected before changes in electropotential. In contrast, toxin from H. carbonum caused a rapid but transient increase in negative electropotential of cells. Carbonyl cyanide m -chlorophenylhydrazone, which (like other metabolic inhibitors) blocks electrogenic pumps, caused cell electropotentials to decrease by approximately 50 mv within a few minutes. This suggests that HV and PC toxins do not have direct effects on electrogenic pumps, but do affect passive efflux of ions, or electrically neutral ion exchange systems, across the plasma membrane.
ISSN:0032-0889
1532-2548