Start earlier, spend more on fungicides this season

Be prepared to start earlier and spend a little extra on wheat fungicide programmes, even on disease-resistant varieties such as Robigus, this season.


The reason: The threat from high levels of over-wintered disease to crops with good yield potential.


“Good emergence and the mild winter weather has left crops well set, with good rooting systems.


They have tremendous yield potential, now we need to feed and protect them,” says CPB Twyford agronomist Simon Francis.


“But be warned, they have a lot of disease – 2006 is looking like a high disease pressure year.”


Already, yellow rust infections have been identified, brown rust and mildew are common, and septoria is present at high levels, notes BASF stewardship manager Rachel Mee.


“Inoculum carry-over from pre-Christmas has been high, so robust fungicide programmes will be vital this year.”


Growers need to start fungicide programmes earlier with a T0 spray to ease the pressure at T1, even on varieties like Robigus, Mr Francis suggests.


“This is the year to invest.


Put your money into T0 and T1 sprays, with a view to making savings later.”


It will probably mean spending a little more – maybe 60/ha – on Robigus this season to keep it clean, he admits.


“But you’ll definitely be better off compared with what you need to spend on more septoria-prone varieties.”


The focus should be on controlling yellow rust in Robigus.


“Use a rust-active triazole at T0, and follow up with Tracker at T1, it adds some stem-based activity.”


BASF and CPB Twyford believe the use of strobilurins remains cost-effective, particularly in flag leaf and ear sprays.


The latter’s 24m farmer-applied strip trials certainly appear to back that view.


Robigus treated with two strobilurins – Opera on the flag leaf and Swing Gold on the ear – yielded over 1t/ha more than where the strobilurin was missed, CPB Twyford’s Lee Bennett reports.


“It was worth an extra 34/ha in margin.”


In 13 BASF comparisons where the addition of 100g/litre of pyraclostrobin was the only difference between two 5ha farmer treated blocks, 12 produced an economic response to the strobilurin, Mrs Mee says.


“The potential is there for a 30/ha benefit.”


mike.abram@rbi.co.uk