Resistance Management - UPL OpenAg

Weeds Resistance



Italian Ryegrass (Lolium multiflorum L.) is an annual winter plant, widely used as a forage crop, stubble-mulching farming for no-tillage, mainly in the Southern States.

The convenience and ease-of-use that glyphosate provided to control this plant resulted in the repetitive use of this herbicide, benefiting the development and increase of biotypes resistant to this mechanism. However, it is important to make it clear that herbicides do not make plants resistant; they only act as selective agents between species.

The ryegrass has long cycle, which varies from 120 to 150 days, and has easy seed dispersion, which shows more expressive development during colder months. Its production potential is approximately 3,500 seeds per plant.

How to manage

Graminicides control both resistant ryegrass and sensitive. In cases of winter crops, it is recommended the use of selective herbicides. It is worth pointing out that even with the use of graminicide, it is also required glyphosate application to control broadleaf weeds (dicotyledons) present in the crop. When there is a high infestation, desiccation may be done prior to crop planting, having as an alternative the non-selective herbicide.

Prevention Indication

  • Herbicide rotation with different mechanism of action;
  • Crop Rotation;
  • Scouting early resistant plants;
  • Certified seed use and quality seed;
  • Performing sequential application of herbicides with different modes of action;
  • Weed Seed Bank depletion Practices and reposition avoidance;
  • Machinery and Implements Cleaning to avoid Ryegrass seed dispersion.

Select One Pack Action Video

Watch the trials with Select One Pack performance on glyphosate resistant Ryegrass and Sourgrass.



UPL has in its portfolio solutions which provide support in Ryegrass management avoiding yield and quality losses in the crop. Click on the image to know more about each product.