Fungitoxicity of some higher plant products against Macrophomina phaseolina (Tassi) Goid

Extracts of leaves and seeds of 15 angiospermic taxa were tested in vitro against the mycelial growth of Macrophomina phaseolina (Tassi) Goid. Amongst them the essential oil of seeds of Trachyspermum ammi L. (Sprauge) exhibited absolute toxicity against the test fungus. The minimum inhibitory concentration of Trachyspermum ammi seed oil was 200 ppm, which exhibited a fungistatic nature, but not phytotoxic properties, when tested at 100, 200 and 300 ppm on seed germination of the French bean (Phaseolus vulgaris L.). The oil exhibited a broad fungitoxic spectrum, inhibiting the mycelial growth of a number of fungi at 100, 200 and 300 ppm. The oil was thermostable and more efficacious than some synthetic fungicides, viz., Benlate, Ceresan, copper oxychloride, Dithan M‐45 and Thiovit. Thymol was also isolated as a fungitoxic factor and it exhibited toxicity against the test fungus at 300 ppm. Copyright © 1998 John Wiley & Sons, Ltd.