Abstract
During the screening of leaves of some angiosperms for their volatile fungitoxicity, Adenocalymma allicea exhibited the strongest activity, completely inhibiting the mycelial growth of a test fungus, Drechslera oyzae. The active principle was isolated in the form of a volatile oil which was found to be fungicidal at its minimum inhibitory concentration of 500 ppm. It inhibited heavy inoculum and exhibited a quick killing action as well as thermostable toxicity. The oil also exhibited a broad fungitoxic spectrum and was found to be more active than some commercial fungicides tested; it was found to be non-phytotoxic to the host plant, stimulatory to nitrate reductase activity and able to prevent leaf-spot disease of paddy.
