中文摘要：

以克劳氏芽孢杆菌（Bacillus clausii）S-4碱性果胶酶诱导黄瓜黄化苗，研究了该激发子对黄瓜生理生化特性的影响，来探究碱性果胶酶诱导黄瓜抗病的机理。结果表明，黄瓜黄化苗经碱性果胶酶诱导后，过氧化物酶、多酚氧化酶和过氧化氢酶活性上升，可溶性蛋白和维生素c含量升高，丙二醛和游离脯氨酸含量下降，活性氧自由基产生速率受到抑制。可见，克劳氏芽孢杆菌S-4碱性果胶酶诱导黄瓜抗病作用与植物体内多种防御相关物质的诱导密切相关。

英文摘要：

Alkaline pectinase from Bacillus clausii S 4 was tested for its ability to induce changes of physiological and biochemical characters in cucumber seedlings, attempting to unveil the mechanism of induced disease resistance. Af ter treatment with alkaline pectinase, the contents of peroxidase, polyphenol oxidase, catalase, soluble protein and Vc increased significantly; on the contrary, the contents of free proline, malonaldehyde and production velocity of re active oxygen radica decreased. These results indicated that the plant disease resistance induced by alkaline pectinase was associated with the elicitation of various defense related substances in cucumber seedlings.