Biological controls options could be part of an integrated approach to disease control following the loss of chlorothalonil (CTL).
Speaking at the Biosolutions hub, Dr Tomas McCabe, lecturer at University College Dublin said: “We are looking at how we develop a strategy going forward, and the options we have to use alongside systemic fungicides, which are still going to be very much central and main players.
“Folpet is the nearest thing to CTL in terms of it how it can perform in the field. It is not as good as or cost beneficial for various reasons but it’s a very serious option.
“We also have in recent times been refocussing on old, traditional contact-type options like sulphur, and increasingly what the options are for various biological control options.
“Many companies will now have biofungicide research as part of their portfolio, and it is very much seen as having a role scientifically in integrated disease control strategies. The general opinion is that they should help in reducing the risk of fungicide resistance development in the future.”
This would need to be combined with a ‘general integrated disease control scenario’, he said, utilising resistant varieties, late sowing dates and in combination with mainstream, single site fungicide options.
Dr McCabe added: “Realistically I’ve seen no examples yet where biological control options could totally replace the main fungicides options.”
Reviewing this year’s trials data on the laminarin based fungicide, Iodus, which focussed on early season disease control for septoria at T0, Dr McCabe said: “These trials show a range of 30-40 per cent efficacy, where we focus on disease control in leaf 2 and 3.
“Efficacy levels [of biofungicides] are within a broad range of 30-60 per cent efficacy, but even the single sites fungicides are more like 50-75 per cent efficacy now.
“Biologicals are more likely to be good used earlier, and as a preventative type treatment. We don’t see good examples yet of where curatively they have the same possibilities, but they fit well into this general concept of integrated disease control.”