RACE DIFFERENTIATION IN CEREAL RUSTS 85 



POWERS: I'm not sure about the races they reported on C. ribicola. 

 Weren't there some questions raised about them? * 



DWINELL: From what I understand, that work has not been repeated 

 and they are trying some new experimentation in an attempt to repeat it. 

 They did not have, in fact, different varieties. They were not able to 

 repeat the work so did not appear to have races . 



LOEGERING: What I wanted Powers to tell about was the fact that he 

 has races by differentiation. You tell them so I don't get it mixed up. 



POWERS: This is my talk you're talking about. I prefer to wait 

 until Friday to comment, but in short, yes, we have variation, which 

 would roughly be an equivalent to your cereal rust basis, with Cronartium 

 quercuum. One isolate was obtained from jack pine and the other from 

 Virginia pine. 



