Crops need less nitrogen if they have more ammonium around their roots. Plant breeders are therefore working on crops that release substances from their roots to keep nitrogen in ammonium form. The first wheat varieties with this trait are expected on the market in five years.
Plant breeders are developing crops that actively counteract nitrogen losses. Roots of these crops release substances that reduce the transformation of ammonium into nitrate. These compounds – they are called nitrification inhibitors – inhibit the soil organisms that are responsible for this transformation process.
A larger proportion of ammonium in the soil is beneficial for the environment. Ammonium is less mobile in the soil than nitrate, which can seep into the groundwater and end up in drinking water. In addition, nitrate can be transformed by bacteria in the soil into nitrous oxide, a potent greenhouse gas. Whether crops themselves benefit from a high ammonium content in the soil has not yet been sufficiently investigated, according to an analysis by the popular science magazine Plant nutrition courier.
For decades, scientists have been looking for ways to improve nitrogen use by crops. This could reduce nitrogen fertilisation rates and reduce losses to the environment. One of the possible measures is the addition of synthetic nitrification inhibitors to fertilisers. Biologists have discovered grasses that have natural variants of these nitrification inhibitors in their roots. Plant breeders have transferred this trait to wheat. The first wheat varieties with these nitrification inhibitors are expected on the market in five years. Research into maize and rice with these inhibitors in the roots is in full swing. Scientists have high hopes for crops that release natural nitrification inhibitors.