SUMMARY: Culture filtrates of contain two heat-stable substances that inhibit infection with plant viruses. One is trichothecin, an antifungal substance with the molecular formula CHO; it sometimes visibly damages bean leaves. The other was isolated as a polysaccharide, [α] = -33°; it contains 1.1--1.4% nitrogen, yields 60--70% reducing sugars (as glucose) on acidic hydrolysis, and the predominant (45%) component sugar is -galactose. The polysaccharide does not combine with tobacco mosaic virus

The extent to which infection is inhibited depends on the species of the host plant but not on the identity of the virus. Trichothecin, like ribonuclease, is relatively more effective with beans than with , whereas the polysaccharide and two derivatives of trichothecin (trichothecolone and acetyltrichothecolone) affect more than beans. Trichothecin inhibits infection when sprayed over leaves a day after they have been inoculated with viruses, but is ineffective when applied 2 days before. The polysaccharide inhibits when sprayed over leaves before inoculation but not after. It is suggested that inhibitors act by temporarily altering the metabolism of leaf cells so that introduced virus particles cannot multiply and are inactivated.


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error