TECHNICAL U P D AT E
DISEASE CONTROL
PREVENTION LEADS IN FUNGICIDE TRIALS Following the recent loss of the curative active ingredient, iprodione, STRI tests whether preventative disease control programmes can outperform curative options
B By Colin Mumford Bayer technical manager
ayer, Headland Amenity and Rigby Taylor joined forces with STRI to compare preventative and curative programmes, and to highlight how Microdochium Patch can be minimised by taking a different approach. As anticipated, preventative treatments performed significantly better on the trial plots. The trial compared spray programmes across nine preventative and three curative programmes, as well as one untreated plot. STRI analysed plots for turf quality, colour and presence of Microdochium Patch over a nine-month period at the site in Bingley, Yorkshire. The first three preventative programmes, P2 to P4, used purely preventative fungicides from Bayer including Dedicate and Exteris Stressgard. The rest of the preventative plots used a combination of these fungicides with additional plant health products from Rigby Taylor and Headland Amenity – and these saw the most consistent results. There were peaks and troughs of disease activity as expected over the course of the trial, with October and December seeing spikes. However, it’s also important
to note that the disease pressure at the trial site wasn’t as strong as general trends across the UK. Plots P5 to P7 had the greatest level of control for Microdochium Patch. But plots P6 and P7 particularly excelled due to the combination of fungicides and plant health products. The differences between turf quality on the plots were less obvious but followed a similar trend. Overall the preventative programmes had better turf quality than the curative programmes. Again, plots P6 and P7 showed the most consistent results throughout the whole trial. Turf colour followed a similar pattern, with treatments on P6 and P7 once again showing the most consistent colour throughout. None of the trial plots were treated with any cultural or biological controls during the nine months, other than mowing and switching when necessary. This is because we wanted to understand the differences that preventative or curative applications alone would achieve.
PLANNING AHEAD
During the trials, even the ‘strongest’ curative programme was significantly outperformed by the preventative options. With the extreme stress turf has endured this summer, it’s important that both cultural and biological practices are used to reduce the risk of Microdochium Patch this autumn. In particular, groundsmen should study historic weather conditions as well as the local forecast to help identify favourable disease conditions. This will help with planning preventative fungicide applications ahead of potential disease-inducing conditions. This autumn we will continue our research to see how we can improve on current disease management programmes. Visit the companies’ websites for more information about their plant protection products: Rigby Taylor www.rigbytaylor.com; Bayer www.environmentalscience.bayer.co.uk; Headland Amenity www.headlandamenity.com
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The trial analysed plots for the presence of Microdochium Patch
34 THE GROUNDSMAN August 2018
www.iog.org THE GROUNDSMAN 33