THE AUTHORS 



RAYMOND J. HOFF is principal plant geneticist on the Station's 

 genetics and pest resistance research work unit located 

 at Moscow, Idaho. Dr. Hoff received a B.A. in biology 

 (1957) from Western Washington State University and a 

 Ph.D. in botany (1968) from Washington State University. 

 He has been working on the development of western white 

 pine resistant to blister rust since 1964. He also 

 investigates resistance to other pests in white pine and 

 other conifers. 



GERAL I. McDonald is principal plant pathologist on the Station's 

 genetics and pest resistance research work \init located 

 at Moscow, Idaho. Dr. McDonald received his B.S. in forest 

 management (1963) and Ph.D. in plant pathology (1969) 

 from Washington State University. He has been investigating 

 the genetic interaction of the blister rust organism and 

 its hosts as well as epidemiology of blister rust since 

 he joined the Station in 1966. 



RESEARCH SUMMARY 



Twenty-five years of research and development has succeeded 

 in producing a new rust-resistant variety of western white 

 pine. Nonetheless, this new variety lias limited levels of 

 resistance and no improvements in other traits. The authors 

 describe a nursery test designed to produce a population of 

 western white pine possessing many mechanisms of resistance, 

 broad adaptability, and increased growth. Mechanisms of 

 resistance (low needle spot frequency, slow canker appears, 

 slow canker growth or tolerance) and growth rate will be 

 selected on a family basis. Individuals exhibiting needle 

 spot prevention, low needle spot frequency, premature needle 

 shed, short shoot reaction, bark reactions, and accelerated 

 growth will be selected from within these families and used to 

 establish seed orchards. The authors propose separating the 

 inland region into hazard zones and managing natural stands to 

 develop resistance. 



