REFERENCES 



Baumanis, L; Pirags, D.; Spalvins, Z. 1982. Resistance 

 trials of Scotch pine clones in the Latvian SSR. In: 

 Resistance to disease and pests in forest trees: Pro- 

 ceedings of the third international workshop on the 

 genetics of host-parasite interactions in forestry. 

 Wageningen, The Netherlands: Center for Agricultural 

 Publishing and Documentation: 448-449. 



Harvey, G. M. 1976. Epiphytology of a needle cast fungus, 

 Lophodermella morbida, in ponderosa pine plantations in 

 western Oregon. Forest Science. 22: 223-230. 



Hoff, R. J. 1985. Susceptibility of lodgepole pine to the 

 needle cast fungus Lophodermella concolor. Res. Note 

 INT-349. Ogden, UT: U.S. Department of Agriculture, 

 Forest Service, Intermountain Forest and Range Experi- 

 ment Station. 6 p. 



Martinsson, 0. 1979. Testing Scots pine for resistance to 

 Lophodermium needle cast. Studia Forestalia Suecica. 

 150: 1-63. 



Merrill, W.; Kistler, B. R. 1976. Seasonal development and 

 control of Lophodermium pinastri in Pennsylvania. 

 Plant Disease. 60: 652-655. 



Mitchell, C. P.; Millar, C. S.; Haworth, M. N. 1976. Effect 

 of the needle-cast fungus Lophodermella sulcigena on 

 growth of Corsican pine. Forestry. 49: 153-158. 



Rehfeldt, G. E. 1980. Cold acclimation in populations of 

 Pinus contorta from the northern Rocky Mountains. 

 Botanical Gazette. 141: 458-463. 



Rehfeldt, G. E.; Wykoff, W. R. 1981. Periodicity of shoot 

 elongation among populations of Pinus contorta from 

 the northern Rocky Mountains. Annals of Botany. 48: 

 371-377. 



SAS Institute, Inc. 1982. SAS user's guide: statistics. 

 Cary, NC: SAS Institute. 494 p. 



Scholz, F.; Stevens, B. R. 1982. Buffering of pH in plant 

 organs and resistance against fungi. In: Resistance to 

 diseases and pests in forest trees: Proceedings of the 

 third international workshop on the genetics of host- 

 parasite interactions in forestry. Wageningen, The 

 Netherlands: Center for Agricultural Publishing and 

 Documentation: 176-186. 



Skilling, D. D. 1975. Lophodermium needle cast of pines. 

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 Agric. Handb. 470. Washington, DC: U.S. Department 

 of Agriculture, Forest Service: 67-68. 



Skilling, D. D.; Nicholls, T. H. 1971. Lophodermium 

 pinastri— a new disease problem in Scotch pine 

 Christmas tree plantations. Plant Disease. 55: 

 1116-1117. 



Squillace, A. E.; La Bastide, J. G. A.; Van Vredenburch, 

 C. L. H. 1975. Genetic variation and breeding of Scots 

 pine in the Netherlands. Forest Science. 41: 341-352. 



Steel, R. G. D.; Torrie, J. H. 1960. Principles and pro- 

 cedures of statistics. New York: McGraw-Hill. 481 p. 



Hoff, R. J. 1988. Susceptibility of ponderosa pine to the needle cast fungus Lophoder- 

 mium baculiferum. Res. Pap. INT-386. Ogden, UT: U.S. Department of Agriculture, 

 Forest Service, Intermountain Research Station. 6 P- 



In 1985 a needle cast caused by Lophodermium baculiferum Mayr severely infected 

 a provenance test and a progeny test of ponderosa pine located in northern Idaho. 

 Populations of ponderosa pine from northern Idaho-northeastern Washington and 

 western Montana differed in their susceptibility to needle cast. Geographic area 

 accounted for most of the variation among populations; elevation accounted for very 

 little. The populations in the north-central portion of the collection area were most 

 resistant, and these were connected with the more susceptible southern populations 

 by gentle dines. Family heritability was 0.60; for individuals it was 0.45. 



KEYWORDS: disease resistance, Pinus ponderosa, heritability 



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w U.S. GOVERNMENT PRINTING OFFICE: 1988—573-039 61.050 REGION NO 8 



