INVESTIGATIONS OF POTATO WART. 19 
munity and then carefully supervise the propagation of seed from it 
before it can be certified for use in quarantined areas. 
The results of the adaptability tests of the selected wart-immune 
varieties would seem to indicate that these can be profitably used in 
the quarantined areas of Pennsylvania. However, should the use of 
wart-immune varieties become necessary in other sections of the 
State where less favorable temperature and moisture conditions 
obtain, it will be necessary to provide wart-immune varieties better 
adapted to such conditions. Since the possibility of the spread of 
the wart into other sections of the State is a threatening factor, con- 
tinued efforts should be made to develop immune varieties of such 
diverse types that one or more of these varieties will be available for 
the commercial or home potato grower in every part of the State. 
