Penetration, Translocation, and Toxicity of Glyphosate in Bermudagrass (Cynodon dactylon)

A 3.6 g/L solution of glyphosate [ N -(phosphonomethyl)glycine] applied to selected parts of bermudagrass [ Cynodon dactylon (L.) Pers.] shoots did not kill the entire plant. However, phototoxicity increased as more parts of the plant were treated. No differences were observed when solutions of 3.6 and 5.4 g/L glyphosate were applied at 94 and 373 L/ha. However, greater herbicide efficacy was obtained when 1.8 g/L solution was applied at the higher volume. Translocation of this herbicide appeared to follow the typical source-sink relationship. A 7.2 g/L solution of glyphosate applied at 373 L/ha was necessary to kill the plant.