Abstract: The prevalent analysis of kiwifruit bacterial canker for several years showed that the effective ecological factors of severe degree were the precipitation (x₁) in the second and last ten days of March,and the average temperature (x₂) of January.The model was y=2.1359+0.0107x₁-0.6061x₂.The main factor of the prevalence was the relative variation of ten days average temperature and precipitation in Winter and in early Spring,and the regression equation was y=-8.127+22.739x-13.254x².The forecast effect of the equation was obviously significant after testing.

Key words: Kiwifruit bacterial canker, Pseudomonas syringae pv. actinidiae, Prevalent forecast, Main factor of forecast, Relative variation, Regression equation, seedling accumulation, stable nitrogen isotope, ¹⁵N labeling method, seed dispersal.