烟草花叶病普遍率与严重度的关系及感病品种与转基因抗病品系间的比较

THE RELATIONSHIP BETWEEN INCIDENCE AND SEVERITY OF TOBACCO MOSAIC DISEASE,AND A COMPARISON B ETWEEN THE SUSCEPTIBLE CULTIVAR AND A TRANSGENIC RESISTANT LINE

利用田间调查取得的数据,分析了烟草花叶病在转基因抗病品系上和感病对照品种上的普遍率与严重度的关系(I—S)。结果表明感病品种的I—S关系以指数函数拟合较好;在普遍率小于35%左右时可以用直线方程(b_1)拟合。在转基因抗病品系上I—S关系呈现为直线方程(b_2)。b_1、b_2两直线方程的斜率不同,感病品种的斜率显著大于转基因抗病品系的。根据两品种(系)间的I—S关系的显著差异,从流行学角度探讨了转基因抗病品系对压低流行强度的作用、并分别用抗感品种(系)建模以外的另一种数据对利用普遍率估测严重度的可行性进行验证,抗感品种(系)预测的平均准确度分别为85.9%和83.3%、

The relationship between incidence and severity of tobacco mosaic diseasecaused by TMV and CMVwas btudied through field investigation.The resultsshowed that the best way to describe the I-S relationship of the susceptiblecultivar(NC89)might be expressed by exponential function when theincidence under 75%.While the I-S relationship could be described withLinear function when incidence was below 35%.Nevertheless,the I-S relationship of transgenic resistant line could only be described with linear func-ion.The I-S relationship for Nc89 was significantly different from that oftransgenic resistant line.The slope coefficient of NC89 was significantly higherthan that of transgenic tobacco plants.This indicated that the resistance ofthe transgenic resistant line significantly affect I-S relationship,mainly dueto the suppression of severity development.Some other data from field surveywere used to validate the I-S relationship models.The average accuracy ofsusceptible cultivar(NC89)and transgenic resistant line are 83.3% and 85.9%respectively.