While conditions so far this season have not had a big impact on mycotoxin risk scores because the two biggest factors are rainfall during flowering and rainfall at harvest, the late season may affect T3 applications and growers should remain on top of potential risks, according to Dr. Simon Oxley, senior research and knowledge transfer manager with the Home Grown Cereals Authority in the UK.
"Many wheat crops are behind, which means they are likely to move rapidly through the growth stages later in the season," said Oxley. "After ear emergence, growers need to be ready to get on with the right T3 for their crops and ensure it is recorded as part of the risk assessment." Higher dose rates at T3 can reduce the overall risk from fusarium mycotoxins. Growers should have already completed the pre-flowering part of their risk assessment, taking into account the effect of cultivation, previous crop, variety and region.
There are a number of other key points growers need to keep in mind when filling in risk assessments, according to Oxley. "It shouldn't be assumed that last year's risk will be the same as this year's, as the amount of rain at flowering and harvest can make a big difference to the risk this season," he said. "Fields with the same agronomy, previous crop, sowing date and rainfall can be covered by one risk assessment. However, it is advisable not to rely on one risk assessment for the whole farm.
"Finally, at harvest, if grain with different risk scores is mixed in stores then the higher risk score should be taken as the score for all the grain," said Oxley. "Growers may, therefore, want to consider storing grain with a higher risk separately."