Submitted to: Weed Science Society of America Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 2/11/2004
Publication Date: 2/11/2004
Citation: Vaughn, S.F., Isbell, T., Weisleder, D., Berhow, M.A. 2004. Field pennycress (thlaspi arvense l.) seedmeal: a potential biofumigant [abstract]. Weed Science Society of America Meeting. p. 71.
Technical Abstract: Defatted field pennycress (Thlaspi arvense L.) seedmeal was found suppress seedling germination/emergence and biomass accumulation when added to a sandy loam soil containing annual ryegrass (Lolium multiflorum Lam.), white mustard (Brassica hirta L.) and sicklepod (Senna obtusifolia (L.) H.S. Irwin & Barneby) seeds. Covering the pots with petri dishes containing the soil-seedmeal mixture increased phytotoxicity, suggesting that the phytotoxins were volatile. CH2Cl2, MeOH and water extracts of the wetted seedmeal were bioassayed against wheat and sicklepod radicle elongation. Only the CH2Cl2 extract was found to be inhibitory to both species. Analysis of the CH2Cl2 extract identified the major phytotoxins as 2-propen-1-yl (allyl) isothiocyanate (80.9%), and allyl thiocyanate (18.8%). In field studies where seedmeal was applied at 0.5, 1.25 and 2.50 kg/m2 and tarped with black plastic mulch, all of the treatments significantly reduced dry weight of bioassay plants as compared to the tarped control, with the highest seedmeal rate decreasing dry matter to less than 10% of control 30 days after seedmeal application. From the results of this study, field pennycress seedmeal appears to offer excellent potential as a biofumigant for high-value horticultural crops for both conventional and organic growers.