Submitted to: Weed Science Society of America Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 2/6/1997
Publication Date: N/A
Technical Abstract: Crambe (Crambe abyssinica Hochst. ex. R. E. Fries) is an industrial crop grown in North Dakota for its oil which contains high levels of erucic acid. Crambe seeds and the resulting seedmeal obtained after oil extraction contain glucosinolates. Certain glucosinolates and their degradation products have been shown to be potent inhibitors of weed seed germination and growth. We are examining the use of extracted crambe seedmeal as a soil amendment to reduce weeds and soilborne pathogens in potatoes and other horticultural crops. Crambe seedmeal added to both sandy and sandy loam soils inhibited hemp sesbania [Sesbania exaltata (Raf.) Rydb. ex. A. W. Hill] at 0.1% (w/w), although wheat (Triticum aestivum L.) was significantly inhibited by crambe seedmeal only at levels of 1.0% (w/w) or higher. Dichloromethane, methanol and water extracts of the seedmeal were prepared and bioassayed against both hemp sesbania and wheat. Only the methanol extract exhibited phytotoxicity against the bioassay species at 1 mg/ml when added to water agar. The methanol extract was fractionated by high performance liquid chromatography and one active fraction was found. This fraction contained one major peak which was identified by gas chromatography-mass spectrometry as 2-hydroxy-3-butenylnitrile.