Diagnosing Group A herbicide damage in canola

These are post-emergent grass control herbicides used for annual ryegrass and/or wild oat control in wheat, barley and broadleaf crops or non-selective grass control in broadleaf crops. Group A herbicides are generally safe on canola, but Dims may cause damage and yield loss.

Distorted flowering spike, flowers and pods
'Gummed-up' flowers that are retained causing aborted or malformed pods
Early damage causes darker, bent down leaves
Curled sometimes scorched leaves
Fops chemical name Example trade name
Clodinafop-propargyl Topik®
Diclofop-methyl Hoegrass®
Fenoxaprop-p-ethyl Wildcat®
Diclofop-methyl fenoxaprop-p-ethyl Tristar®
Fluazifop Fusilade®
Haloxyfop Verdict®
Quizalfop Targa®
Propaquizafop Correct®
Dims chemical name Example trade name
Tralkoxydim Achieve®
Clethodim Select®
Tepraloxydim Aramo®

What to look for

    Paddock

  • Vegetative stage: areas of dark green distorted plants particularly where plants are stressed.
  • After stem elongation: reduced flowering and distorted heads on sprayed areas.

    Plant

  • Mildly damaged vegetative plants are dark green and cupped downwards with minor leaf spotting and scorching, before recovering.
  • Flowering plants are smaller and produce fewer smaller flowering spikes.
  • Flowers may appear gummed-up, resulting in distorted heads, reduced pod set, and distorted pods.

Where did it come from?

  • Spraying stressed plants.
  • Higher application rates.
  • Use of non-recommended adjuvants.

Topics

Page last updated: Wednesday, 12 July 2017 - 12:29pm