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U.S. DEPT. OF AGRICULTURE MISC. PUB. 939 



ment of poplar and Allium plants, as well as through flowers and seeds 

 originating from infected plantations. Transference by unsterilized 

 cuttings is also a possibility. 



Range : This parasitic organism is present all over Europe but espe- 

 cially heavy infections of poplars have been recorded in the south- 

 ern and central parts. 



Hosts: Many species, cultivars, and clones belonging to the sections 

 Aigeiros and Tacamahaca may be attacked. The appended table 

 shows the relative susceptibility of many poplars but variations 

 from this listing are possible. Susceptibility depends upon the 

 origin of reproductive material as well as upon geographic loca- 

 tion and climatic conditions. Among the widely used euramerican 

 cultivars, cv. "serotina" proved to be one of the most susceptible. 



Poplar Susceptibility and Alternate Hosts for Melampsora 

 allii-populina kleb. 



Species aud resistance 



Low: 



Populus nigra-italica 



P. thevestina 



P. berolinensis 



P. regenerate, 



P. serotina 



P. backelieri 



P. monilijera 



P. robusta 



P. vernirubens 



Medium : 



P. marilandica (Yugosl.) _ 



P. jremontii 



P. balsamifera 



P. gelrica 



P. wislizenii 



P. nigra (Yugosl.) 



P. deltoides 



I-A55 (Yugosl.) 



1-476 (Yugosl.) 



High: 



P. nigra (Czech.) 



P. marilandica (Czech.) _ . 



1^55 (Czech.) 



1-501 



1-159 



1-45/51 



1-214 



Alternate hosts 



Allium ascalonicum 



A. carenatum 



A. cepa 



A. moly 



A. oleraceum 



A. sativum 



A. schoenoprasum 



A. spaerocephalum 



A. ursinum 



A. vineale 



Literature : 



F.A.O. Poplars in forestry and land use. Home, 1958 : 330-333 ( Sec- 

 tion : Diseases of poplar, T. R. Peace, United Kingdom) . 



Gremmen, J. Op Populus en Salix voorkomende Melampsora-soorten 

 in Nederland. T. PL ziekten, 60 : 243-250. 1954. 



Leontovyc, R. Napadnutie jednotlivych klonov topolov hrdzou 

 Melampsora allii-populina Kleb. v. selekcnej velkoskolske Gabci- 



