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Since its launch in 1974, Roundup has been first choice for non-selective chemical weed control for farmers across the world. Used for controlling weeds in stubbles and stale seedbeds, patch control of noxious weeds, harvest management and grassland reseeding, Roundup and its active substance glyphosate is remarkably versatile and effective. It is relatively simple to use but don’t let that be a reason for complacency, ensure you optimise performance and prevent resistance with effective product stewardship.

Using Roundup on Farm

Mode of Action

Once applied to the leaf uptake occurs within 1-6 hours and glyphosate moves through the phloem both downwards and upwards within 5 days. It tends to accumulate in the growing points, then evens up throughout the plant, leading to a gradual loss of green colour followed by death between one and four weeks later.

Glyphosate works at a single specific site in the Shikimic acid pathway to inhibit the production of the amino-acids phenylalanine, tryptophan and tyrosine. Amino- acids are the building blocks of protein molecules and once the biochemical pathway is blocked the synthesis of proteins is interrupted and the plant effectively starves to death. The process is temperature related and explains why treated plants take some time to die.

Environmentally Friendly

This metabolic pathway is present only in green plants. Higher forms of life like mammals, birds, fish and insects are dependent on plant sources to obtain these three amino-acids in their food and neither absorb nor metabolise glyphosate. This is the reason Roundup has such environmentally friendly characteristics.

No other class of commercial herbicide is known to target this site (HRAC group G).

Glyphosate Formulations

All glyphosate products are not same. While they all contain the active ingredient, glyphosate, the formulation type in which the glyphosate is carried plays a major role in performance.

Our formulation chemists have worked continually since the launch of Roundup to bring out new formualtions with improved weed control, leass restrictive conditions of use and better safety profiles under COSHH.

Modern formulations of Roundup are highly active and provide the highest levels of uptake and translocation leading to improved speed, rain fastness and efficacy.

Find out more:

Autumn weed management success

Tips for glyphosate efficacy ahead of autumn drilling;

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Glyphosate Stewardship

Attention to detail is essential for resistance management

Applied correctly, glyphosate as a non-selective herbicide can deliver very high levels of weed control. As such, it has become one of farmers’ most trusted weed management tools. However, experience around the world shows that glyphosate is not invincible, weeds can develop resistance to it.

Fortunately, there are no known cases of glyphosate resistance in the UK but weed biologists agree that the risk is there. Once weeds become resistant, there is no cure, so taking steps to reduce the risk is essential for farmers to retain this versatile and highly effective herbicide.

In 2021, the Weed Resistance Action Group (WRAG) published updated guidelines to minimise the risk of glyphosate resistance developing in the UK. This booklet guide builds on their recommendations and Bayer’s expertise with Roundup (glyphosate) products to give farmers and agronomists an effective framework to ensure the long-term efficacy of glyphosate.

Glyphosate Stewardship

Applied correctly, glyphosate as a non-selective herbicide can deliver very high levels of weed control. As such, it has become one of farmers’ most trusted weed management tools. However, experience around the world shows that glyphosate is not invincible, weeds can develop resistance to it. Our guide provides information on reducing those resistance risks.

    Download the booklet

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