A GOOD spraying programme could help keep disease pressures at bay, agronomists have warned.

Dry conditions experience this April, followed by a very wet May, has resulted in taxing conditions for potato and cereal growers UK.

Director and Senior Agronomist at Scottish Agronomy, Eric Anderson, explained, “Ware growers who started planting in the colder soil temperatures of April, got through the planting season uninterrupted, however, seed growers who delayed planting waiting for the soils to warm up were caught out by the heavy rain in May. So many seed growers began planting in May, but it was then almost a month before they got back to the same fields. This has given a strong challenge in that potatoes have been emerging over a period of 6 to 7 weeks from planting whereas normally they would emerge 3- 4 weeks from planting.”

Crops are now growing very vigorously, with some emerging now into very warm ambient air conditions which means even more rapid growth and challenges from late blight.

Mr Anderson continued: “With the crop canopy doubling in height almost every seven days, unless growers are using fungicide products with truly systemic activity then it is difficult to get the new leaves protected against late blight. We are also faced with night temperatures which are now commonly above 10oC, an arbitrary threshold in relation to late blight within the crop and weather which is conducive to late blight. It is certainly challenging.”

A very wet May has also brought high foliar disease pressure to cereal crops. In winter wheat, the highest level of Septoria since 2012 has been recorded.

BASF Agronomy Manager, in Scotland, Scott Milne, said: “In some areas, inputs were reduced at T0 and T1 and there is definitely a difference to be seen between a good spray programme and a weaker spray programme and in any programme that has been stretched between T1 and T2 then there are issues to be seen. The main take home messages have very much been the correct product and the correct timing. If you don’t get the T1 right then you can’t claw it back.”