Setaria glauca

Yokum et al. (167) have studied the properties of a germination and growth inhibitor produced by Setaria glauca (yellow foxtail). The inhibitor was heat-stable, dialyzable, neutral, and nonnitrogenous. The authors suggested that it was a carbohydrate. 

Setaria glauca (L.) Beauv. or S. lutescens Weigel (F.T. Hubb) foxtail, yellow... 

Metabolism of the proherbicide (i.e., a non-phytotoxic chemical that requires metabolic conversion to yield an active herbicide) FE, is an example of how Phase 1 and II metabolism, and use of a safener imparts selectivity between crop and weed species (Figure 1). FE is used to control many graminaceous weed species such as Avena fatua, Echinochloa crus-galli, Digitaria ischaemum, and Setaria glauca (40) in wheat which is moderately tolerant to this proherbicide. The primary basis for the selectivity of FE in grasses is due to differences in metabolism (40-42). FE is rapidly hydrolyzed to the herbicide fenoxaprop (F) in wheat, and in all the previously mentioned graminaceous weeds (4J). In wheat. 

Green, J. M., and Hale, T., Effect of Adjuvant Type on the Control of Yellow Foxtail (Setaria Glauca) with Nicosulfuron, Proceedings Weed Science Society of America, 43 58,2003. 

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