| The epidemiology and forecast technology of shoot blight of pinus sylvestris are studied by biometric and ecology methods, according to the theories and researching methods of forest epidemiology, ulimately, we provide theory base for efficient contrlo of this disease .Forestry elements(tree species, standage,afforestation density etc), ecological elements (hillside direction, hillside seat, soil type etc) and meteorological elements (temperature,humidity, precipition etc) were the leading factors by the correlation analysis of qualitative and quantitative factors of epidemiology of spore dispersing and disease state observation.The result of dusting analysis of 22 counties and cities in Heilongjiang Province was the division of the risk grade of shoot blight of pinus sylvestris into 4 districts that were seriously occurring district, commonly occurring district, occasionally occurring district and safely district, according to nine weather factors which was closely correlated to the shoot blight. It was almost identical with the fact of disease investigation in field .Exponential, Weibull and Richards models were tested for appropriateness with the successive disease date observation monthly in the fixed plots of Shangzhi in growing season in 2000 and 2002, by nonlinear regression analysis. The Weibull model was superior for discribing the temporal dynamics of Shoot blight of pinus sylvestris. Moreover, it was also showed that the disease was a compound interest disease caused by polycyclic pathogen.The multi-variant linear regression forecasting equation y=-10.6+1.241yO+0.288t was established by stepwise varibale selection of the meteorological factors for disease index y observed in the fixed plots of Shangzhi, initial disease index and the temperature in last month were selected into the model. The correlation-coefficient r = 0.962 and it was significant at P-value less than 0.01 level. The accuracy of the model was higher by examing with the data inside and outside modle.
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