Many fungicides on which narcissus growers once relied are no longer available so new options are needed.
In HDC project BOF 072, 15 fungicides were compared in programmes with an emphasis on effectiveness, resistance management and harvest interval. The project was extended for a year (BOF 072a) to continue monitoring treated plots to gain more data on smoulder control and find out to what extent treatments made in 2012 affected disease levels and crop performance in 2013.
"Identifying new fungicide programmes gives us a much better chance of managing these diseases cost-effectively into the future," says Mark Clark of Grampian Growers.
The results so far show that white mould manifested as the main disease in the trials, with very little smoulder. Several fungicides were more effective than Amistar (azoxystrobin), the current industry standard. Up to three sprays applied immediately after flower picking, using two or more of these products, controlled white mould well and markedly deleted senescence.
Preliminary results suggest treatments that delayed senescence last year led to improved flower cropping this year and fungicides that reduced white mould in 2012 resulted in less white mould this year. Some of the fungicides have already been adopted into commercial disease-control programmes.
Horticultural Development Company
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