North: Perfect recipe for explosion of crop disease

At last a bit of a cold spell. Autumn has drifted into winter with less sunshine, more water, less frost and higher average temperatures. A perfect recipe for an explosion of disease once crops start to develop.

Those wheat crops which escaped the December floods have wintered well and most grew faster than slugs could eat. Some have been grazed down by geese. Those with leaf cover are carrying traces of over-wintered disease, particularly septoria. However, if the current cold snap is prolonged it may assist in damping down disease pressure. If that ideal scenario proves not to be the case then we should expect a high pressure season.

Thus we will definitely require a solid T0 followed by a planned approach to protection, backed up with multisite actives to try to minimise the inexorable advance of disease resistance. Working around the early fungicide spray will be the need to get on with weed control, as the wet back end prevented most sprayers from travelling in the autumn.

The nitrate vulnerable zone (NVZ) shutter rises in a fortnight’s time, but most crops will only require a wee kick-start of nitrogen.

In general winter barleys have established well and apart from those with roots in wet patches they have remained green throughout. As with wheat, early disease – mildew, rhyncosporium and net blotch – are present and similarly a T0 treatment will be required. Alternating chemistry to try to outwit disease resistance will be the order of the day. A top up of manganese at this timing will assist in maintaining green leaf area.

Oilseed rape crops seem to be at about the right stage i.e. not too proud. Light leaf spot was easy to find in the autumn, so in those crops where the ground conditions defeated the sprayer, a twin spray treatment may be required. The first one substituting for the missed autumn application. Getting nitrogen on once growth commences will be a priority.

Unfortunately, the hottest topic of conversation these past few weeks has been CAP reform. It is a disgrace that we are already a month into the new scheme and all the rules have not yet been finalised. Undoubtedly there will be some who may already, unwittingly, have transgressed. Hopefully the consequences will not be too costly.

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