Diagnosing glyphosate damage in field peas

Glyphosate is a systemic knockdown herbicide that is used extensively for brown fallow, summer weed or pre-seeding weed control, or selective weed control in glyphosate resistant crops.

The first sign is yellowing/ reddening and sometimes interveinal chlorosis of new growth
Tendrils and leaves become wilted and necrotic and the plant dies

Group M: Glycines

Chemical name Example trade name
Glyphosate

Many including Glyphosate®

Touchdown®

Roundup®

What to look for

    Paddock

  • Limp discoloured plants that may slowly die.
  • Direct spray damage is uniformly distributed but varies with spray coverage on overlaps or boom turns.
  • Spray drift damage is worse near the source.

    Plant

  • The first sign is pale new growth that may contain red colours and have interveinal chlorosis.
  • Chlorotic areas become necrotic and the plant wilts and dies.

What else could it be

Condition Similarities Differences
Diagnosing virus damage in field peas Young growth interveinal chlorosis Patchy distribution, plants do not rapidly die.
Diagnosing group F herbicide damage in field peas Pale leaf blotches and streaks on sprayed leaves. Plants recover.
Diagnosing contact herbicide damage in field peas Chlorosis and death. Damage appears rapidly with dessication of sprayed parts.
Diagnosing group C herbicide damage in field peas Chlorosis and death. Damage progresses more slowly, and starts in older growth.

Further information

Where to go for expert help

John Moore
+61 (0)8 9892 8476
Page last updated: Wednesday, 13 May 2015 - 1:50pm