14 March 1996

MAP is best route to lifting your yields

MONO-AMMONIUM phosphate placed with maize seed at drilling increases yields by 5% to 10%.

Maize Growers Association agronomist Simon Draper says that MAP promotes root development which is vital for a well established crop and faster early growth. Because the maize grows faster in spring the crop also matures more quickly, cutting the growing period by a week.

And Mr Draper says that the response occurs even when soil indices for phosphate are high. This is because phosphate is relatively insoluble and even when present may be unavailable to the maize plant.

Mr Draper recommends that between 40kg to 50kg/ha (32-40 units/acre) should be applied with prills placed 2.5-5cm (1-2in) below and to one side of the maize seed. This ensures that as the root tip progresses downward it remains close to the fertiliser prill.

"Applying MAP at this rate would cost about £25/ha but the increase in yield could be worth about £125/ha and harvest is brought forward by a week," says Mr Draper.

"However, when phosphate is drilled under an inch from the seed it will cause the root to burn off while MAP drilled over two inches away will not reach the root," he warns. &#42


PHOSPHATE


&#8226 Promotes root development.

&#8226 Applications can increase yields by 10%.

&#8226 Place with seed at drilling.