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Tomato (Solanum lycopersicum) is one of the most important crops and a known host of broomrapes. The species of genus Orobanche are biotic stress factors restricting plant growth and crop production. Some natural compounds and chemicals affect this biological relationship. Therefore, in the present study, the effect of gallic acid and kiwi fruit extract on the biological relationship between broomrape and tomato plant was investigated. To this end, first, the symbiotic effect of the broomrape species, Orobanche aegytica, on growth parameters of tomato plant and the amount of soluble sugar and photosynthetic pigments were evaluated. Then, the effect of concentrations of gallic acid and kiwi fruit extract at different levels on this biological relationship was investigated by measuring the growth parameters of tomato and broomrape, photosynthetic pigments and the amount of soluble sugar in tomatoes. The results demonstrated that the broomrapes reduced the fresh weight and dry weight of the stem, leaves and roots of tomato, diminished the leaf area of the host plant, and decreased the amount of photosynthetic pigments and its soluble sugar content. Gallic acid treatment and kiwi fruit extract lessened the growth parameters of the broomrape species and its overall growth, in addition to increasing the growth of tomato plants. This process could be associated with the constraint of the biological relationship between the parasite and the host, as the soluble sugar content as well as the amount of the photosynthetic pigments of tomato plants were increased and the tomato plants remained highly resistant.