Abstract: After comparing two different methods for the induced resistance to Sphaerotheca fuliginea(Schlecht), the leaf-disc method was established and was considered as a simpler, more effective and more accurate method than field identification method. Then seven chemicals and their combinations were systemically compared the induction effect on resistance to Sphaerotheca fuliginea(Schlecht). The results showed that OAA, SA, matrine, PTU, complex phosphorus showed significant induction effect, whereas their effect is OAA＞SA＞matrine＞PTU＞complex phosphorus. KCl and MnSO4 did not show the significant induction effect. When combined the organic inducers with inorganic inducers, the results showed that the combination of PTU, matrine with MnSO4, KCl or complex phosphorus respectively, the induction effect were significantly enhanced, whereas SA and OAA combined with inorganic inducers, the induction effect were significantly reduced. This may be related to the interaction between ions.

Key words: Induced resistance, Sphaerotheca fuliginea(Schlecht), Cucumber(Cucumis sativus var Xintaimici), Chemicals