The dry weather has resulted in smaller wheat flag leaves, which could mean lower leaves have a bigger influence on wheat yields this season.
That is according to Bayer technical manager Gareth Bubb, who says smaller than usual flag leaves are evident at Bayer’s development site in Callow, Herefordshire, where time-lapse cameras are providing real-time images of crop and disease development.
“This year it has been really noticeable that the flag leaf is much smaller than it should be, there is a big difference between the size of the flag leaf compared to leaf 2. I suspect this could be due to the dry weather,” he says.
As a result, leaf 2 could contribute more to final yield than the flag leaf, which typically accounts for up to 50 per cent of wheat yields, he adds.
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He says: “More yield could come from the lower leaves, in particular leaf 2 and 3, especially in some of the more open or prostrate crops such as Siskin. So farmers which have not gained adequate protection of leaf 2 and 3, could suffer a yield hit.”
Plots at Callow were nearing the T3 timing ahead of the Bank Holiday weekend, with most varieties approaching early flowering, although some milling varieties were slightly ahead.
“At T3, timing is critical. It needs to be applied at early to mid-flowering. If it is too early or too late then fusarium will not be controlled,” says Mr Bubb.
This season a foliar top-up may be required at this timing to keep the upper leaves greener for longer, he adds.
"Growers may need to consider a foliar top up as well, because if they did not get their T2s exactly right, they probably need some extra activity against septoria."