Herbicidal efficacy and selectivity of pyribenzoxim in turfgrasses

Abstract

Three field trials were conducted from 2003–2004 at Utsunomiya University, Japan, to evaluate the safety and herbicidal activity of pyribenzoxim (benzophenone O‐[2,6‐bis[(4,6‐dimethoxy‐2‐pyrimidinyl)oxybenzoyl]oxime) in turfgrass. Pyribenzoxim showed a high level of safety in bentgrass (Agrostis palustris Huds.) and zoysiagrass (Zoysia matrella) ≤ 300 g ai ha−1 and it controlled various major grass weeds, including annual bluegrass (Poa annua L.), large crabgrass (Digitaria sanguinalis L.), and green foxtail (Setaria viridis L.), and broadleaf weeds, including common dandelion (Taraxacum officinale Weber), horseweed (Erigeron canadensis L.), shepherd’s‐purse (Capsella bursa‐pastoris (L.) Medic.), common chickweed (Stellaria media L.), common lambsquarters (Chenopodium album L.), creeping woodsorrel (Oxalis corniculata L.), and common dayflower (Commelina communis L.) by fall or spring application. In comparison with bispyribac‐sodium (sodium 2,6‐[bis(4,6‐dimethoxy‐2‐pyrimidin‐2‐yl)oxy]benzoate), pyribenzoxim showed a higher safety level in bentgrass and a stronger herbicidal activity on grass weeds; in particular, annual bluegrass and large crabgrass.