Lack of consensus on efective approaches for Egyptian broomrape (Phelipanche aegyptiaca) management in host plants has focused attention on the identifcation of resistant or tolerant genotypes by evaluating plant physiological responses to parasitism. In the current study, the response of 35 cucumber (Cucumis sativusL) genotypes to Egyptian broomrape parasitism was investigated in a completely randomized design with 4 replications. Parasitism by Egyptian broomrape led to a signifcant decrease in shoot and root dry weight of C. sativuscompared to the control treatment which varied across diferent genotypes. Parasitism resulted in signifcant but variable increases in hydrogen peroxide, malondialdehyde, protein and phenolic compound content across all genotypes. Catalase-specifc activity, ascorbate peroxidase and peroxidase in Egyptian broomrape-infected treatments also difered to that in control treatments. In addition, underground attachments number plant −1 (UAN), emerged spikes number plant −1 (ESN), total attachment number plant −1 (TAN), attachment dry weight (g)/plant −1 (ADW) were signifcantly diferent among various cucumber genotypes. As a result of our analysis, genotypes were classifed into four clusters. The Khassib greenhouse genotype was diferent to other genotypes with increases in total phenolic compound content and catalase activity being higher compared to the other three clusters. At the same time, shoot dry weight losses, malondialdehyde enhancement and UAN traits in Khassib had the lowest values compared to the other genotypes when parasitized by broomrape.

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