Revolutionary weed control – five years on

In 2020, KWS UK Ltd and Bayer  launched CONVISO® SMART to the UK market.

The aim of this system was to transform sugar beet farming through a high-performance weed control approach that combines two key components: herbicide-tolerant KWS varieties and CONVISO® ONE, a precision-targeted ALS herbicide.

CONVISO® SMART provides effective control over both broadleaf and sensitive grass weeds.

This system allows growers to reduce spraying to just one application while still managing problem weeds like weed beet, fat hen, and annual mercury effectively.

Since its launch five years ago, the system has gained popularity among many growers. Let’s explore why.

How the technology works

KWS’ SMART seed varieties are specially bred to be tolerant of CONVISO® ONE. Developed by Bayer, CONVISO® ONE is a herbicide designed to be used with KWS SMART  seeds.

The herbicide features two active ingredients, foramsulfuron and thiencarbazone-methyl, and is approved for a single 1-litre/ha application.

Both ingredients are ALS inhibitor herbicides,  however the foramsulfuron acts as a contact herbicide, while thiencarbazone-methyl works through both the leaf and soil, providing long-lasting residual effects.

Offering benefits beyond the control of weed beet

CONVISO® SMART offers growers a unique weed control performance combined with the best crop safety.

The herbicide has very good efficacy on target weeds, controlling both broad-leaved weeds and ALS sensitive grassweeds.

The system is also effective on weed beet, making it an appealing option for growers looking to bring fields with a known weed beet problem back into production.

But the benefits don’t stop there. South Lincolnshire grower, Edward Dowler, has used the SMART system for the past 2 years.

Despite not being in a high-pressure weed beet situation, he has found benefits in other areas and has been impressed with the system.

“2024 marked our first year with the CONVISO® SMART system.

“We grew 50ha of SMART RIXTA KWS, which accounted for about half of our sugar beet area,” says Ed.

The system’s promise of effective weed control with just one application, as opposed to the three sprays typically needed for conventional systems, was particularly appealing.

“The prospect of fewer sprays was attractive to us, as we believed it would simplify management and logistics,” Ed adds.

“We farm a block of beet 25 miles away from our base. With the SMART RIXTA crop only needing a single spray, it made sense for us to reduce our sprayers busy workload for this block,” he says.

The CONVISO® ONE had a registered application window from the 4 true leaf stage (BBCH 14) up to and including the 8 true leaf stage (BBCH 18) of sugar beet.

For 2025 this has been expanded to applications from expanded cotyledons (BBCH 10) up to and including the 8 true leaf stage (BBCH 18) of sugar beet.

The old registered application window contrasts with conventional systems that usually target weeds when they’re most vulnerable.

The crop did not receive any pre-em applications prior to the CONVISO® ONE.

“It was very unnerving seeing how forward the weeds were getting, but I trusted by agronomist’s experience with CONVISO® SMART beet and sure enough, the CONVISO® ONE herbicide did its job effectively.

We did not need to add any additional herbicides, so we were very happy with the overall weed control,” Ed recalls.

While the system comes at a higher cost than Ed’s traditional methods, he believes the savings from reduced workload are difficult to quantify.

“In terms of logistics, the system works really well for us. It simplifies weed control, with application timing being more flexible than with conventional herbicides.

“When we’re busy or under pressure, we don’t need to worry so much about timings being comprised. We have peace of mind knowing that the crop’s safety is ensured, and that’s something you can’t put a price on.”

Following a successful 2024 season, the CONVISO® SMART system will be used on the farm again this year.

“The system has eased workloads, streamlined agronomy, and proved gentler on the crop.

“We’ll plant SMART VESNICA KWS in the blocks farther from the farm, while continuing with our conventional ANNATINA KWS at the base farm, which has delivered positive results for the past two years,” says Ed.

SMART variety performance

KWS’ SMART seed varieties have been developed to carry the specific tolerance to the ALS-inhibitor based herbicide, making them suitable for using alongside the CONVISO® ONE herbicide.

When the system was introduced in 2020, trial data showed that classic varieties offered a significant yield advantage over the SMART varieties.

Growers understood that choosing CONVISO® SMART sugar beet would result in a yield reduction, but they saw the system’s other advantages as a valuable trade-off that made it worthwhile.

“As with any new trait, there is typically a yield lag for a few years until the new traits are yielding on par with the highest yielding elite varieties.

Five years later, thanks to ongoing improvements in breeding, the yield gap between classic and SMART sugar beet has significantly narrowed,” explains Martin Brown, KWS Beet Product Manager.

He continues, “The launch of our first SMART variety, SMART JANNINKA KWS, which was added to the 2020 BBRO Recommended List, this had a yield of 90.1%, 12% lower than the highest-yielding classic variety at the time, BTS 860.

Fast forward to the 2026 BBRO Recommended List, and our highest yielding SMART variety, SMART UMA KWS, boasts a yield of 94.1%, just 7.1% lower than the highest-yielding classic variety, BTS1915.

This yield is from using solely classical herbicides and does not take into account the crop safety aspect offering a yield uplift by using CONVISO ONE.

Using only CONVISO ONE you can expect an average 6% yield uplift, putting SMART UMA KWS on par with some of the highest yielding classic varieties.”

Martin also highlights that the new SMART varieties offer not only improved yields but also better disease resistance and lower bolting  numbers.

A key development within the CONVISO® SMART system is the introduction of the first SMART variety with Beet Cyst Nematode (BCN) tolerance.

“Beet cyst nematode poses an increasing threat to British sugar beet crops, and growers have requested a variety combining the CONVISO® SMART trait with BCN tolerance since the launch in 2020 .

“We’re really pleased to introduce SMART NELDA KWS to the market. In areas where nematode populations have built up due to tight rotations, SMART NELDA KWS can offer an effective solution,” says Martin.

SMART NELDA KWS has now been added to the 2026 BBRO Recommended List

Martin concludes, “This is another significant milestone in KWS’s breeding journey.

“We have additional trait  combinations for the CONVISO® SMART system in development and look forward to continuing to meet growers’ evolving needs.”