RELATIVE BLISTER RUST RESISTANCE OF XATIYE AND 

 INTRODUCED KHITE PINES IN ASIA 



B. K. Bakshi 

 ? crest Pathology Branch, Forest Research Institute, Dehra Dun, India 



.ABSTRACT 



Relative white pine blister rust resistance of six Asian 

 5-needle pines {Pinus armandii, P. sibirica, P. pumila, P. 

 wallichiana (synonym P. griffithii) , P. koraiensis and P. 

 r 2i--:if':r-z) in indigenous locations, and also of P. strobus 

 and P. ayacahuite introduced in Asia is discussed. Of these, 

 P. wallichiana, P. koraiensis and P. sibirica are attacked by 

 the blister rust but are fairly resistant, and the remaining 

 species have not been found to be reported as attacked by the 

 rust in Asia. A rust reported to be Cronartium ribicola has 

 been reported but not verified in Japan; C. ribicola is 

 definitely present in South Korea both on Ribes and P. 

 koraiensis , if at different localities on each of these hosts 



Peridermium indicum , the aecial stage of C. ribicola on Pinus 

 wallichiana, is, at least morphologically, distinct from 

 Peridermium strobi , the aecial stage of the rust on Pinus 

 strobus. 



Intensive surveys, critical morphological study of C. 

 ribicola based on the material collected all over the world, 

 and cross inoculation experiments are suggested to determine 

 the bearing of biological phenomena (especially racial 

 diversity and possible autoecism) in C. ribicola on the 

 relative blister rust resistance of 5-needle white pines. 



INTRODUCTION 



Of the almost 20 species of white pines in the world, 15 are impor- 

 tant as forest and timber trees. Five of these — Pinus armandii Franch . , 

 ?. sibirica Du Tour, P, wallichiana A. B. Jackson (syn. P. griffithii 

 McClell.). P. koraiensis Sieb. £ Zucc. and P. parviflora Sieb. & Zucc.-- 

 are indigenous to Asia. P. pumila Regel is also very widespread, if not 

 a timber species, in eastern Asia. Relative resistance of these 

 indigenous Asian pines to white pine blister rust (pathogen Cronartium 

 ribicola J. C. Fisch. ex Rabenh.), and also susceptibility of other white 

 pines introduced in Asia are discussed below. 



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