Hydro-Agri's new tractor-mounted N-sensor, which will be on display at this year's major shows, is being tested in field trials.

Last year's single sensor, mounted at the front of a tractor, has been replaced with a front-mounted boom with eight sensors, pictured left, giving a more complete picture of the crop. The sensors measure the reflection of light, which relates to nitrogen status. That information is fed into an on-board computer which can combine it with other data such as yield maps and determine the required rate of fertiliser application.

Dr Stephan Reusch, who invented the N-sensor, said it had the potential to improve both yields and profitability of cereal production.