Plaxium® performs strongly in AHDB trials

Plaxium^®, Bayer’s first co-formulation fungicide to contain Iblon^® (isoflucypram) has performed strongly in AHDB trials delivering the greatest control of brown rust, was comparable to other products against Septoria tritici and was either better or equal to other products against yellow rust. 

This performance was repeated in the barley trials where it gave the best all-round control of Rhynchosporium, net blotch, ramularia and powdery mildew. 

Plaxium^®, a three-way formulation containing isoflucypram, fluopyram and prothioconazole, received regulatory authorisation in late 2024 and will be available to growers for use on wheat and barley this season. 

In data published to highlight its performance in trials between 2019 and 2021, the AHDB noted that “Plaxium^® was shown to be highly effective against Septoria tritici in both protectant and eradicant situations”.   

Septoria control

Plaxium^® performed comparably to other fungicides against Septoria tritici in both protectant (left) and eradicant (right) situations 

Reference: AHDB, 2025. Protectant: 16 trials, 2019-21. Eradicant: 10 trials, 2019-21 

Yellow rust control

Against yellow rust, the AHDB noted that Plaxium^® “showed a level of activity above that seen from Ascra^® Xpro^® and Revystar^® XE, comparable to Univoq^®, and close to that of Elatus^® Era. These differences were carried through to harvest with Plaxium^® treated plots yielding comparably to Univoq^®”. 

Plaxium^® gave greater yellow rust control than Ascra^® Xpro^® and Revystar^® XE and comparable with Univoq^® 

Reference: AHDB, 2025. 4 trials, 2019-21. 

Brown rust control

On brown rust, the AHDB noted that “Plaxium offered superior control compared with other mixture products tested… and was comparable in efficacy to Imtrex^® (fluxapyroxad) and Elatus^® Plus (benzovindiflupyr).” 

Plaxium^® delivered outstanding control of brown rust, eclipsing the performance of other mixtures tested 

Reference: AHDB, 2025. 3 trials, 2019-21. 

The results highlight the consistency of performance of Plaxium^® against the principal foliar diseases of wheat and over contrasting seasons.  

Niab’s Stuart Knight, a trial partner, praised the efficacy and yield response of Plaxium^® saying: “The trials indicate a clear efficacy and yield response advantage of Plaxium^® compared with Ascra^® Xpro^®. This reflects the boost to foliar disease activity provided by isoflucypram, in place of bixafen in this three-way mixture.” 

Barley fungicide performance

The barley disease trials assessed Plaxium^®’s control of Rhynchosporium, net blotch, ramularia and powdery mildew. Plaxium^® showed good control of all four diseases.  

Against Rhynchosporium, in both protectant and eradicant situations, the AHDB noted that, Plaxium^® gave “excellent control of disease control, comparable to or better than Siltra^® Xpro^® and Ascra^® Xpro^®, and similar to the level of control provided by the solo active, Miravis^® Plus”. 

Similarly, “against net blotch, Plaxium^® showed a very high level of efficacy even at 50% of label rate, performing comparably to Miravis^® Plus and Ascra^® Xpro^®.” Against ramularia, Plaxium^® matched the control of Revystar^® XE and was slightly better than Ascra^® Xpro^®. 

SRUC’s Professor Fiona Burnett, a trial partner, highlighted the performance of Plaxium^® and combination of multiple modes of action along with the restrictions on use that would ensure good product stewardship, saying: 

“Plaxium^® adds another robust mixture option for control of barley diseases and is carefully stewarded to manage resistance risk.” 

Against powdery mildew, the AHDB noted that although disease pressure was relatively low in these trials, “Plaxium^® gave the highest level of protectant activity of any of the mixture products tested”.  

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Plaxium® contains isoflucypram, fluopyram and prothioconazole. Ascra® Xpro contains bixafen, fluopyram and prothioconazole. Elatus® Era contains benzovindiflupyr and prothioconazole. Elatus® Plus contains benzovindiflupyr. Revystar® XE contains fluxapyroxad and mefentrifluconazole. Imtrex® contains fluxapyroxad. Univoq^TM contains fenpicoxamid and prothioconazole. Plaxium, Ascra and Xpro are registered trademarks of Bayer. All other brand names used are Trademarks of other manufacturers in which proprietary rights may exist. Use plant protection products safely. Always read the label and product information before use. Pay attention to the risk indications and follow the safety precautions on the label. For further information, including contact details, visit www.cropscience.bayer.co.uk or call 0808 1969522. © Bayer CropScience Limited 2025