<正>结合杨树褐斑病发病过程，测定黑杨派六个无性系在生长季碳水化合物的变化动态。在病害浸染初期，抗病无性系（Ｉ－６３杨、Ｉ－６９杨、Ｉ－７２杨）叶部还原糖和可溶性糖含量较感病无性系（Ｉ－２１４杨、Ｐ１５Ａ杨、加龙杨）低且呈下降趋势，感病无性系则呈上升趋势。侵染初期抗病无性系叶部总糖含量高于感病无性系。抗病无性系茎部输送的糖较感病无性系多。各无性系秋季运输的糖较夏季多。

ln relation to the pathogenesis of Marssonina leaf blight in natural environment,dynamics of carbohydrates in six Aigeros clones was detected. During the early stage of pathogenesis of Marssonina leaf blight,the concentration of soluble and reducing sugars in leaves of susceptible clones(I-214,P15A and“blane de garonne”)was higher than those resistant ones (I-63,I-69,I-72).The contents of sugars increased in susceptible clones and decreased in resistant ones.On the contrary, the concentration of total carbohydrate in leaves was lower in susceptible clones than in resistant ones during the period. The content of sucrose in stem bark was higher in resistant clones than in susceptible ones.The bark sucrose in autumn was higher than in late summer.