关键词: 杨树, 溃疡病, 常量元素, 树皮

Abstract: A preliminary study on the relation of the macronutrients in the bark of Populus tomentosa Carr., P.×euramericana(Dode) Guinier, P. nigra var. thevestina to Dothiorella gregaria Sacc. was carried out by using statistical analysis. The results of correlation analysis as well as principal component analysis show that the percentage of conidia germination of D. gregaria Sacc. and colony growth appear to be negative correlation with nitrogen, sulphur, phosphorus, calcium and magnesium, and to be positive correlation with potassium, nitrogen the effect of which is the most significant. Futhermore, the results from two-dimensoinal classification of samples show that there are significant differences in the contents of six macronutrients and the resistance to D. gregaria Sacc. amoug various poplar species, thus providing the theoretical basis for selecting poplar varieties with strong resistance to D. gregaria Sacc. In the early stage.

Key words: Poplar, Dothiorella gregaria, Macronutrient, Bark