Nov. 15, 1925 
Longevity of Teliospores of Cronartium ribicola 
915 
SUMMARY 
During the summer of 1923 telia from eight Ribes hosts were 
tested for longevity. Under outdoor conditions their longevity 
varied from 19 days for one collection of Ribes rotundifolium* to 87 
days for R . nigrum, which still germinated well at the end of the 
experiments. 
The “ floating” method of germination was much superior to the 
damp-chamber method. 
Precooling per se did not seem to stimulate germination of telio¬ 
spores markedly. Tests are needed to prove whether decided 
alternations in temperatures are not the stimulating factors. 
The period of germination of teliospores increases with their age, 
whether kept dry indoors or outdoors exposed to the weather. 
Uredospores accompanying the teliospores remained viable for a 
maximum period of 59 days under the conditions of these experi¬ 
ments. 
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