T3 still the most important spray to reduce mycotoxins in wheat
With recent research stating that the use of certain products at various timings has an effect on levels of Fusarium ear blight, the key message remains the same: the T3 spray is the most effective timing to have a significant effect on Fusarium infections.
Recent trials conducted by Professor Simon Edwards of Harper Adams University College (HAUC), on behalf of BASF, shows that the most significant reductions of Fusarium Head blight were achieved at T3 using Brutus.
The trials conducted at the HAUC site on Solstice the Group 1 milling wheat with a head blight resistance rating of 6, were infected with F. graminearum and F culmorum resulting in high head blight disease pressure and DON production.
We looked at the effect of Brutus and Opus on Fusarium to evaluate Fusarium head blight control, explains Professor Edwards. The most effective timing for Fusarium head blight control was at T3 with 74% reduction of head blight compared to the untreated control, which is highly significant. Whilst there was some level of control at both previous timings, it was the T3 spray which had the greatest effect across this trial.
There was also a significant reduction in the concentration of DON in harvested grain, with Brutus applied at T3. There was no significant interaction between the timings, indicating that activity of sprays at other timings (T1 and T2) had little impact on the efficacy of Brutus at T3. Percentage control achieved at T1 and T2 were 27 % and 22% respectively, but compared to the effect at T3, it was relatively low.
Professor Edwards continues: In terms of overall yield, specific weights and TGW, Brutus did have an effect at each timing. Yield responses were very good due to the high disease pressure, with a 272% greater yield for the spray regime containing Brutus at T1, T2 and T3, compared to the fully untreated control.
In summary, these trials show the advantages of using a loaded triazole product such as Brutus in high disease pressure scenarios at T3 in terms of reduction of Fusarium head blight and also associated yield benefits – there is no question that the formulation benefits highlighted previously by Jonathan Blake of ADAS, come into play.
Whilst there were some benefits of control from applying Brutus at T1 and T2, Fusarium control at these earlier timings is a secondary consideration, and should not form the basis of decision making for these sprays – which should be focussed on controlling stem and foliar diseases, advises Professor Edwards.
It may however affect product choice at these timings, he adds. For example when two products have equivalent foliar disease control but one, like Brutus, also has good activity against Fusarium head blight.
Peter Hughes, Fungicide Product Manager at BASF agrees with these findings. However Mr Hughes is keen to emphasise that mycotoxins are a seasonal and regional issue:
NABIM figures show that the percentage of crops with DON that were greater than 1000 ppb (limit in grain is 1250ppb) were 6.2% in 2007, 9.5% in 2008 and 0.6% in 2009 demonstrating seasonal variations.
Yield is key, and the focus of programmes should concentrate on protecting against foliar and stem based disease at T1 and T2, and then using an effective Fusarium product at T3 to maintain quality. Independent work is showing Brutus is at least alongside the standards for Fusarium and mycotoxin reduction, but there is the additional benefit of superior yields, plus leading Septoria and rust control.
For grain traders Dalmark Grain, based in Peterborough, they are keen to point out that the decision to grow a milling wheat starts with varietal choice and from then on there is a commitment to grow for quality, as well as yield. The risk of losing the valuable premium as a result of mycotoxin contamination is possibly more important at todays low prices so when feed prices are at 90/tonne and full spec milling wheat premium is at 20/tonne this increase of 20% in the value of the crop is certainly worth protecting, says Farm Business Manager Chris Tye.
About BASF
BASF is the worlds leading chemical company: The Chemical Company. Its portfolio ranges from chemicals, plastics and performance products to agricultural products, fine chemicals and oil and gas. As a reliable partner BASF creates chemistry to help its customers in virtually all industries to be more successful. With its high-value products and intelligent solutions, BASF plays an important role in finding answers to global challenges such as climate protection, energy efficiency, nutrition and mobility. BASF posted sales of more than 50 billion in 2009 and had approximately 105,000 employees as of the end of the year.