Disease control in Brussels sprouts and storage cabbage crops is now underway and growers are being advised to implement programmes for a broad spectrum of control for disease threats.

The Allium and Brassica Centre’s Andy Richardson has said first sprays of Nativo 75WG were applied to storage cabbage crops in Lincolnshire in mid July to counter White Blister and Powdery Mildew risk presented by warm, showery weather. These first sprays were also timed to keep older leaves clear of Ring spot.

“So far it’s been too dry for the spotting diseases to get going but as soon as we get some sustained rainfall infection levels will start to build. While Ring spot remains the main threat south of the Humber, Light leaf spot is creeping this way. Dry conditions so far are also likely to make Powdery mildew more of an issue this year,” Richardson warned.

To get the required broad spectrum control, Richardson recommends planning on a four-spray programme including two applications of the triazolinthione fungicide Rudis (prothioconazole), as the second and fourth treatments.

“The recent label extension to include Brussels sprouts will be a big help to growers this year as it’s the most difficult crop to control fungal diseases in. Rudis also delivers strobilurin-like physiological benefits including enhanced greening.” Programmes on Lincolnshire sprouts are due to start in the first week of August he notes.

Vegetable agronomist and grower Matthew Rawson who operates from Yorkshire up into the Scottish borders said Light Leaf Spot is always the major disease worry there in sprouts and cabbage crops. “Rudis is set to be the primary weapon against it this season but growers should also be considering location of crops and cultivar choice,” he said.

For autumn cabbage production Rawson believes the variety Toughma less susceptible than Destiny and for sprout production the variety Dominator is proving more tolerant to Light leaf spot than Millenium. However, cultivar choice has to be balanced with market requirements and the need to maintain continuity of supply.

Topics