Research looks at N efficiency

The three-year study, which will build an understanding of how pasture absorbs and metabolises nitrogen, is being conducted by a Postdoctoral Fellow Jonathan Love and two PhD students at the University of Canterbury.

Ballance research and development manager, Warwick Catto, says improved nitrogen efficiencies can potentially lead to an important secondary benefit of reduced nitrate leaching. This is due to the flow-through impacts on the grazing animal, with improved nitrogen utilisation and therefore less urinary loss.

Postdoctoral Fellow Jonathan Love says while nitrogen is essential to produce enough food for the world's growing population, its efficient use is essential to keep farm expenses down and to minimise the environmental impacts of overuse.

The research will seek to answer three key questions: how is nitrogen uptake regulated in pasture grasses; how can the uptake of nitrogen be improved; and whether combining plant hormones with nitrogen fertiliser will lead to improved efficiency.

"To answer these questions we're looking at external factors like temperature, moisture and nutrient availability as well as the grass's internal mechanisms that send signals within the plant in response to inputs such as nitrogen," Dr Love says.

"Because the plant uptake and response is limited, much of the added nitrogen is never used and then becomes exposed to processes in the soil which result in it being lost to either the atmosphere or groundwater. We hope to improve the upstream processes of uptake and growth response to avoid the downstream losses.

"Ultimately what we're trying to do is help farmers improve the uptake of nitrogen in grass and, therefore, use less of it per hectare to produce the same or more grass growth."