Slow growth of sugar beet this spring meant that two-spray programmes of fungicides might be necessary to maximise yields this year, Syngenta’s Will Holmes has said.

The recent cold, dry weather and frosty mornings had left crops slow to emerge in parts of the UK, he noted.

Growers would need to strongly consider a two-spray programme to bulk up crops, particularly ones likely to be lifted later, he suggested.

Two different strategies could be used, depending on when growers intended to lift the crop.

For crops lifted before mid-October a single spray in July could be sufficient, he said. However, where beet was lifted later, he recommended a two-spray programme.

The firm’s Spyrale (fenpropidin + difenoconazole) fungicide was a good choice where powdery mildew was the main target, while Priori (azoxystrobin + cyproconazole) was better against rust, he said.

A second spray improved green leaf retention in the autumn, he noted. That reduced the risk of canopy collapse, which helped protect against frost and made it easier to harvest.

Independent BBRO trials data have shown that failure to control diseases and maintain green leaf can lead to yield losses of up to 20%.