Chlorothalonil – the active ingredient in Bravo – is up for re-registration and is set to go under scrutiny at a meeting of the Standing Committee on Plants, Animals, Food and Feed (SCoPAFF).
The decision may be taken in October, but could be pushed out to the end of the year.
The broad-spectrum fungicide – which is used in the control of plant diseases – also forms part of an anti-resistance strategy in disease control programmes to back up the chemistry being used.
The importance of Bravo to the Irish tillage sector was stressed at this week’s National Crops Forum, held by Teagasc.
Michael Hennessy chairing the session at the Teagasc National Crops Forum. Image source: Michael Scully
Its role in disease programmes
Bravo plays an essential roll in the control of ramularia on barley, which is a fairly common disease in Ireland and is caused by continued wetness on the plant’s leaves at stem extension. It also plays an important role in the control of septoria on wheat.
Steven Kildea, who is a plant pathologist at Teagasc, stated: “Chlorothalonil is essential at the moment. It’s an anti-resistance measure for septoria and ramularia.”
Steven has assessed chlorothalonil in trials over the years and has really noticed the importance of the active ingredient, as SDHI chemistry declines in efficacy.
We know the efficacy of the current chemistry without chlorothalonil is significantly reduced and is leading to a possibility of losing up to 10% of the potential crop yield without the inclusion of chlorothalonil.
Steven has replaced chlorothalonil with other products in trials and entered the data into profit monitors for 2016 and 2017 (varying grain prices). He estimates a significant drop in net margin on winter wheat crops – falling by 50%.
Barley
“I wouldn’t underscore the value of chlorothalonil in terms of ramularia control because I think we are moving towards a scenario that all of our good chemistry is losing a lot of its efficacy.”
Steven estimates the same loss on both winter and spring barley. When entered into a profit monitor in 2016 and 2017 (varying grain prices), this equated to a decrease of up to 65% in net margin.
In terms of ramularia, it’s a very simple solution.
Steven also commented on the fact that bred resistance will be an important tool in the control of plant diseases, but as varieties get older there is an erosion of resistance.
Syngenta
Syngenta is the company which originally brought Bravo to the market. Since that time, generic forms of the chemical have become available.
Billy Cotter of Syngenta Ireland addressed the crowd at the National Crops Forum: “Bravo has been on the market and in use for 30 years.
“During that time, it has gone through registration and re-registration. It’s now going through it’s latest re-registration process. Unfortunately, the hurdles are getting increasingly high in terms of keeping it on the market.
We at Syngenta are one of the applicants for re-registration and we believe that the science supports the re-registration.
“Registration is essentially a scientific process, but then there is a political interpretation of the scientific evaluation if you like and that is where it is at at the moment. No decision has been taken.
“In terms of the EU, Ireland is certainly going to suffer the most if chlorothalonil isn’t re-registered. I think we need to make it clear to all the stakeholders in the industry how important this active ingredient is.”
Billy also asked the Irish Department of Agriculture to support the product in its re-registration, as well as advocating for chlorothalonil among their EU colleagues.