The allelopathic potential of methanol extract from Sargassum virgatum (Mert.) AG. (Phaeophyta) on the seeds germination and seedlings growth of Lettuce (lactuca sativa), Tomato (Lycopersicon esculentum), and barley (Hordeum vulgare) was conducted. Methanol extracts from S. virgatum at concentrations 25, 50, 100, and 200 ppm were applied under laboratory conditions. Tomato, lettuce and barley g...