ARS | Publication request: Effects of Alternaria destruens, Glyphosate, and Ammonium Sulfate Individually and Integrated for Control of Dodder (Cuscuta pentagona)

Submitted to: Weed Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 11, 2011
Publication Date: October 1, 2009
Citation: Cook, J., Charudattan, R., Zimmerman, T., Rosskopf, E.N., Stall, W., Macdonald, G. 2009. Effects of Alternaria destruens, Glyphosate, and Ammonium Sulfate Individually and Integrated for Control of Dodder (Cuscuta pentagona). Weed Technology. Vol. 23 No. 4 pp. 550-555.

Technical Abstract: Dodder is a serious weed problem in several crops. Its minutely sized, easily dispersed, and highly viable seed makes it difficult to control. Alternaria destruens is the active ingredient in a registered bioherbicide for control of dodder species. In greenhouse studies, the following treatments were applied to citrus parasitized with dodder: an untreated control; oil at 7.5% v/v in water; Alternaria destruens in water at 1.8 x 107 spores per ml; a mixture of A. destruens + oil; ammonium sulfate at 0.125% w/v in water; glyphosate at 0.02 kg ae/L; and a mixture of A. destruens + oil, glyphosate at 0.02 kg ae/L, and ammonium sulfate at 0.125%. The highest disease or damage severity rating out of all treatments, measured as the Area Under the Disease or Damage Progress Curve (AUDPC), was obtained for the mixture treatment (88.90). By 35 days after treatment, all Cuscuta plants treated with the mixture treatment were dead but not the host plant, citrus. These results indicate the feasibility of integrating glyphosate, ammonium sulfate, and A. destruens to manage dodder.