Fenoxaprop for control of yellow bristle grass in pasture and its efficacy on other C4 grasses

Abstract

The eficacy of the herbicide fenoxaprop for control of yellow bristle grass (Setaria pumila) in pasture was evaluated in two ield trials. Additionally, glasshouse experiments investigated its phytotoxicity on seven annual and four perennial C4 grass species. Results of the ield trials showed good control of yellow bristle grass and consequently a very high (up to 98%) reduction in seed head production. Fenoxaprop had no measurable effect on clover yield but the removal of yellow bristle grass resulted in higher production of perennial ryegrass (Lolium perenne). Fenoxaprop killed all the annual C4 species tested, viz. yellow bristle grass, summer grass (Digitaria sanguinalis), witchgrass (Panicum capillare), smooth witchgrass (Panicum dichotomiflorum), barnyard grass (Echinochloa crus-galli), broom corn millet (Panicum miliaceum) and crowfoot grass (Eleusine indica), but was less effective on the perennial C4 grass species, viz. Indian doab (Cynodon dactylon), Kikuyu grass (Cenchrus clandestinus), Mercer grass (Paspalum distichum) and paspalum (Paspalum dilatatum). © 2013 New Zealand Plant Protection Society.