Abstract: Study was conducted to explain the reason why grafted cucumber (Cucumis sativus L. ) performs better than non-grafted one in the respect of resistance or tolerance to biotic orabiotic stresses and photosynthesis. In a plastic chamber, grafted cucumber‘Jinyou 1’ and non-grafted cucumber‘Jinyou 1’were planted in plastic pots filled with pasterised medium consisting of peat, vermiculite and moss. Proteins from the leaves of the two types of cucumber p lants were analyzed in seedling stage, flowering stage and fruiting stage by two dimensional electrophoresis ( 2-DE) and mass spectrum (MS). In the leaves of the grafted‘Jinyou 1’, two types of proteins were found to be induced to higher degree of expression than in the non-grafted plants. The first type of p roteins was R-protein (RGC693) and squalene synthase related to resistance
or tolerance to the stresses. The second was coenzyme which promotes chlorop last synthesize, and chlorophylla-b binding protein which enhances photosynthesis. So the results obtained in this research could partly explain the mechanism of the better stress tolerance and higher photosynthesis in the grafted cucumber plant.

Key words: cucumber, grafted, proteome, R-protein, squalene synthase, chlorophyll a-b binding protein