Tolerance of spring barley ( Hordeum vulgare L.), oats ( Avena sativa L.) and wheat ( Triticum aestivum L.) to saflufenacil

Abstract

Saflufenacil is a new herbicide being developed by BASF for pre-emergence application for broadleaved weed control in maize and other crops. Three field studies were conducted in Ontario, Canada over a 2-year period (2006 and 2007) to evaluate the tolerance of spring cereals (barley, oats, and wheat) to pre-emergence and post-emergence applications of saflufenacil at 50 and 100 g ai ha −1. Saflufenacil pre-emergence caused minimal visible injury (1% or less) at 3, 7, 14 and 28 days after emergence and had no adverse effect on plant height or yield of barley, oats, and wheat. Saflufenacil plus the surfactant Merge (1% v/v) applied post-emergence caused as much as 76, 60, 52 and 35% visible injury in spring cereals at 3, 7, 14 and 28 DAT, respectively. Injury with saflufenacil plus Merge applied post-emergence decreased over time and was generally greater as dose increased. Saflufenacil plus Merge applied post-emergence reduced plant height by as much as 16% and reduced yield of spring barley and wheat by 24 and 13%, respectively, but had no effect on the yield of spring oats. Based on these results, saflufenacil applied pre-emergence at the proposed dose can be safely used in spring planted barley, oats and wheat; however, the post-emergence application of saflufenacil results in unacceptable injury and yield loss. These results are consistent with the proposed pre-emergence use pattern for saflufenacil.