Rothamsted Research scientists are making progress in their efforts to reduce reliance on N fertiliser in wheat crops.

The Wheat Genetic Information Network project funded by DEFRA aimed to improve N use efficiency in the crop, Malcolm Hawkesford of Rothamsted Research said.

The initial research looked at how much genetic variation there was in wheat varieties’ response to N, through analysis of grain N and yield. Further investigation had tried to identify varieties good at either or both taking up N from the soil, and then converting it into grain yield, he explained.

“They are two different processes, which the breeders haven’t separated out when breeding new varieties.”

The researchers were staggered at how much variation there was between varieties, he said. “Some varieties are good at one, but not necessarily the other. It means that there is potential for improvement.”

The next step is pinning down the genetics to understand why. Advanced genetic techniques, such as double haploid mapping, were beginning to find candidate genes for breeders to work with.

“The aim will be to maintain yield with less N, or continue with the same inputs and achieve more yields.”

A realistic target might be to reduce N inputs by 20%, he concluded.