Growers were urged to focus on the rising prospect of a significantly delayed harvest earlier this week, as wet weather continued to blight the country, adding to already severe mycotoxin pressure.
Generally good yield potential was at risk, prompting talk of a second ear fungicide and plans to protect grain quality at harvest.
With most areas receiving 200% of normal rainfall in June, especially around flowering, mycotoxin risk from fusarium head blight was severe, said Simon Edwards of Harper Adams University College.
Slow-maturing, lush crops, with lodging starting to emerge added to the problem. Widespread use of SDHI fungicides, with their ability to extend crop greening, could further delay harvest.
“We are very worried – everything looks set for a bad season,” warned Martin Savage of national milling organisation Nabim. A recent mycotoxin stakeholder group meeting agreed the same approach as the past four seasons, with millers requiring full risk assessment by growers and routine DON testing until mid-September, with some ZON testing likely, too. Results would show whether testing needed to continue.
Prof Edwards urged growers to use the HGCA risk calculator (see www.hgca.com/mycotoxins) as required under Crop Assurance rules, to take proper account of rainfall, variety, T3 sprays and previous cultivations. Guidelines say all grain scoring over 15 must be tested.
Only northern Scotland and the far east of the UK might have recorded anything less than the full nine points for heavy rain at flowering. A further four points for crops grown in the high-risk area, covering most English wheat growing counties, mean almost all crops are close to the 15-point threshold, before any agronomy considerations.
Crops with quality potential will need prioritising at harvest, maybe including desiccation. “Anything that shortens the ripening period and reduces exposure to harvest rainfall could help. A lot depends on the weather between now and harvest,” said Prof Edwards.
While a second ear spray may do little to combat established fusarium, other late diseases need control, particularly if the first ear spray went on early, said Yorkshire AICC agronomist Patrick Stephenson. Label cut-offs could be a challenge, with Swing Gold and Folicur looking the best options, he said.
Reluctant-to-ripen wheat could also benefit from selective desiccant spraying to manage harvest, he added. But plan carefully to allow for combine and store intake capacity.
With £65m invested in large efficient dryers over the past four years, Openfield producer members are well placed to harvest damper crops to safeguard quality. “We can cope with damp grain at all 16 of our stores, from Aberdeen to Cornwall, having handled 27% moisture spring barley and 30% wheat in the past,” said the group’s Rob Sanderson. “We’d rather see lower moisture, but it gives producers the flexibility to harvest at the best time to protect the quality of their crops.”