Improved methods and compositions for protecting plants or seeds from soil-borne fungal diseases. The composition may include a triterpenoid isolated from Glycyrrhiza glabra and a polymer. The triterpenoid may be Carbenoxolone disodium salt, and the polymer may be a water-insoluble, water-soluble or flowable, seed coating polymer. The methods may comprise the steps of applying the composition to the plant's seeds, roots, tubers and/or foliage, and may also include applying the composition to the soil surround surrounding the plant. The composition may be applied as an aqueous solution or as dry particulates, and may be used for the treatment of soybean plants and seeds.