An investigation on tobacco brown spot was made in five representative mountain climate zone of Guizhou province in 2011, so the occurrence data of tobacco brown spot were got, and the flue-cured tobacco variety investigated was yunyan87 which was susceptible to tobacco brown spot. The data were tested by various growth models in SPSS software for curve estimation, and the results
suggested that the Logistic model fitted best by sig value and R2 value comparison in SPSS software. By analyzing the factors of tobacco brown spot occurrence, it indicated that the initial disease, daily mean temperature, relative humidity, wind velocity and the rainfall were
major factors affecting the occurence of this disease. The prediction model for growth rate of tobacco brown spot in field was established using stepwise regression analysis. |