Wheat response to simulated glyphosate drift

Document Type

Article

Publication Date

10-1-2007

Abstract

Glyphosate at simulated drift rates representing 12.5, 6.3, and 1.6% of the usage rate of 1,120 g ai/ha (140, 70, and 18 g/ha, respectively) was applied to wheat at first node, boot stage, or at early flowering. At 14 d after treatment (DAT) wheat injury, expressed as bleaching of leaf foliage and growth inhibition, was 40 to 55% for 70 g/ha applied at first node and for 140 g/ha applied at all growth stages. Wheat height 28 DAT was reduced 47% with glyphosate applied at 140 g/ha at first node and was reduced around 26% for 70 g/ha applied at first node and 140 g/ha applied at boot stage. Wheat height was not reduced with glyphosate at 18 g/ha applied at first node or boot stage and with all rates applied at early flowering. Wheat yield was reduced 72% when glyphosate was applied at 140 g/ha at first node, 45% when applied at boot stage, and 54% when applied at early flowering. For 70 g/ha, wheat yield was reduced 25 to 30% for the three application timings. Wheat yield was not reduced for 18 g/ha glyphosate. In another study, six wheat varieties responded the same to glyphosate applied at 140 and 70 g/ha. Wheat height 28 DAT was reduced an average of 34% for 140 g/ha glyphosate and 17% for 70 g/ha applied at first node, but height was not reduced when applied at early flowering. Yield was reduced an average of 58 and 43% for 140 and 70 g/ha applied at first node and 38 and 19% for 140 and 70 g/ha applied at early flowering. In both studies yield reductions in most cases were reflected in reduced spike density, spikelet number per spike, and seed weight.

Publication Source (Journal or Book title)

Weed Technology

First Page

1010

Last Page

1015

This document is currently not available here.

Share

COinS