Screening pinus sylvestris grown for the production of Christmas trees for resistance to western gall rust Peridermium harknessii using different sources of aeciospores

摘要

Results showed a moderate to high susceptibility of Pinus sylvestris to western gall rust Peridermium harknessii from Pinus sylvestris in Michigan and pinus banksiana in minnesota. In general, Pinus sylvestris seed sources were more susceptible to aeciospores collected from Pinus sylvestris than aeciospores collected from Pinus banksiana.