Take-all dressings will need backing of good agronomy
Take-all dressings will need backing of good agronomy
DO not expect to raise second wheat yields to first wheat levels by simply buying a bag of seed treated against take-all, warns a leading distributor agronomist.
"These products do seem to raise the yield potential of second wheats," says Profarmas agronomy business manager Craig Morgan. "But their benefits are only going to come if growers are prepared to change their agronomic practices as well."
Monsantos coded product and the Aventis treatment based on fluquinconazole are being tested at the firms 4ha (10 acre) trials site at CWS Broadoaks Stoughton Estate near Leicester.
But a closer focus on root growth will be needed to exploit them fully, says Mr Morgan. Light land trials show a closer focus on below-ground plant growth can bring impressive yield increases. "Getting plant rooting structure right makes all the difference."
Heavier land
Since take-all affects plant rooting, it will be important to transfer those management techniques to heavier, take-all prone soils to boost rooting and therefore yield, Mr Morgan believes.
"As well as careful variety selection and bringing seed rates down to allow the plants to develop fully, we are also examining the role of nitrogen in helping to keep the plant going, looking particularly at the amount and timing of applications," he says.
"Phosphate is also important so we are now looking at applying foliar phosphate to boost root development still further. On top of all this we use strobilurin fungicides early to gain maximum advantage from their physiological effects on the crop."
By the time the crop reaches growth stage 31/32 growers will have had to invest more of their management time in their second or third wheat crops, he adds.
But there are other issues to address. "Everyones looking at the benefit of growing crops without having to worry about take-all. But they are missing the likely knock-on effect on the level of stem-base diseases," says Mr Morgan. "Thats why weve been concentrating on the strobilurin kresoxim-methyl which seems to have more activity against eyespot that other strobilurins."
Growing more wheat and therefore fewer break crops also has the potential to trigger bigger grassweed problems, he adds. "Growers will need to take a long-term rotational view using pre-emergence materials to control grassweeds and rotating chemical use to avoid the build-up of resistance. We are no longer talking about programmes for individual fields but programmes for the whole rotation." *
Dont expect anti take-all seed treatments to solve second wheat worries. Improved agronomy will also be needed to make the most of the new technology, says Profarma after trials with the new product.
Open day
New take-all products will feature at the CWS Broadoak/ Profarma Open Days at Cockayne Hatley, Sandy, Beds on 27 and 28 June.