Efficacy of Ethanedinitile( C2 N2 )against Some Cereal Pathogens

摘要

Ethanedinitrile (EDN) is being investigated by CSIRO Australia as an alternative to methyl bromide for a range of uses,including soil and timber fumigation. EI)N is an effective devitalisation agent of cereals and is being evaluated for devitalising feed grain imports into Australia. Part of this process involves assessment of efficacy against target pathogens of concern including Tilletia indica Mitra (Karnal bunt), Peronosclerospora sorghi Weston & Uppal （sorghum downy mildew), Tilletia controversa K hn （dwarf bunt) and Ustilago maydis （DC.) Corda (boil smut), which is being conducted in collaboration with the USDA ARS. This fumigant was tested on:1)naked spores;2)bunted seed,when this is a propagule in the life cycle of the pathogen;3)spores dusted on maize. It was applied at 120 mg/L over a period ranging from a few minutes to 5 days at 5,17 and 22℃. The naked teliospores of the three smut fungi were more easily controlled than spores still contained within the fungal structure. (sorus) or those spores that were dusted onto maize seed, whichwere the most difficult to control. Oospores of S. sorghi germinate poorly, if at all, on artificial medium.Results of the bioassay showed trace infection of sorghum in the untreated controls, and in one plantthat was treated for 1 hr at 17℃.