Green leaf protection to boost late season sugar

Prolonged drought conditions mean sugar beet growers should try to extend the growing season for roots to bulk up and add sugar, says experts.

British Sugar agronomists have reported healthy crops can put on an additional 25% of adjusted yield from mid-September, with sugar content increasing by 0.2-0.4% a week through to November.

“Maintaining green leaf area for as long as possible will be paramount in growers’ decisions for fungicide programmes this season,” says Syngenta technical manager Andy Cunningham.

Powdery mildew has been at high risk for some time, favoured by hot dry conditions. “But as day length now shortens and leaves remain wet with dew for prolonged periods overnight, there’s also increased risk of rust developing very quickly.”

That would be further exacerbated by irrigation of crops during the dry weather, or any isolated rain showers that occur. But Mr Cunningham says Priori Gold provides effective disease protection and the physiological advantage of green leaf retention.

Also marketed by Syngenta as Angle, Priori Gold combines difenoconazole and azoxystrobin for protection against rust, powdery mildew, ramularia and cercospora -– as well as the renowned green leaf retention of the strobilurin active.

Although the hot, dry summer has reduced the risk of ramularia, the disease can still hit later in the season. Growers should be aware of the need for persistent fungicides or a later application to prevent early defoliation, says Mr Cunningham.

In previous seasons, a two- or three-spray strategy has consistently shown the highest yields and best returns. This season, Mr Cunningham says for most growers a two-spray programme will still pay dividends.

“If you do opt for a single treatment, it’s crucial that it is as timely as possible and you seek to get both the disease control and green leaf retention offered by Priori Gold. Retaining healthy green leaf will prove a positive bonus for ease of harvesting.”