The UK's Home Grown Cereals Authority (HGCA) tested the nitrogen requirements of common wheat varieties such as Einstein, Malacca and Xi19 at nine sites and compared the results with other wheats giving higher and lower yields. HGCA director of research Professor Graham Jellis said: "This project aimed to develop optimum nitrogen fertiliser application practices for realising the high yield potential of these wheat varieties whilst meeting the grain protein and baking quality requirements set by both home and export markets." Nitrogen stimulates the production of grain protein in wheat but in the past confusion has arisen for growers over the levels of nitrogen suitable for modern Group 1 and 2 wheat crops which need a higher grain protein content. Around 30 per cent of the UK wheat area is now devoted to Group 1 and 2 wheats but simply upping the nitrogen application for these crops is not a suitable solution given the rising cost of such fertilisers. Lead scientist for the research Peter Dampney said: "With fertiliser prices increasing substantially in recent years the 'breakeven ratio' has likewise increased reducing the economic optimum nitrogen rates. This in turn has made it more difficult to achieve both high yields and the required protein contents." The researchers found that 38 per cent of the modern crops tested needed more than 280kg/ha of nitrogen to achieve a 13 per cent protein content and a quarter of the wheat needed in excess of 300kg/ha. Alternative options such as applying extra nitrogen later in the growing period and varying spray application were also explored in the study. Further information, including the full project report, can be obtained from the HGCA.