Abstract : Oroxylum indicum is an important medicinal plant of Indian Ayurvedic medicine system. The natural population of the plant is nearing to its threshold of extinction. Therefore, its conservation is must and on this aspect an experiment was performed to see the effect of different seed sources and habitats under a single eco-region of Brahmaputra Valley i.e. semi- evergreen forests of Assam on its seed germination by common and feasible natural germination methods. It is found that number of seeds per gram were more (25.66±1.45) in Nalbari seed source than rest of the locations but the seed germination percentage was low or minimum (25-50%) in this seed source and even the seeds were infected with intact seed fungus like Curvularia species while the seed source of North Lakhimpur had maximum seed germination percentage (70-100%) in all the studied treatments followed by Guwahati seed source. The Seedling Emergence Index (SEI) was high (1.0±0.45) in Nalbari seed source whereas minimum (0.00058±0.047) in North Lakhimpur seed source. The more the Seedling Emergence index value, the poorer is the seed germination percentage.

Key words: Conservation, habitat, Oroxylum indicum, seed germination, seed sources