Assessing Nitrogen Fixation - PulseResearch
April 25, 2017
Researchers assess nitrogen fixation of faba bean for the Prairies
One of the goals of a nitrogen fixation project at the University of Saskatchewan (U of S), funded by Saskatchewan Pulse Growers and the Agriculture Development Fund (ADF), was to devise a simple labbased chemical method to screen field plants for better nitrogen accumulation through biological nitrogen fixation.
“Legume and pulse crops can fix nitrogen in nodules on their roots, so they do not need fertilizer nitrogen applications,” says Dr. Rosalind Bueckert, a U of S professor of plant sciences, and the lead researcher of the project. “Biological nitrogen fixation is nature’s way of producing seed with greater protein levels, such as we see in pulse, peanut, and soybean crops.”
Because legumes generally have high protein levels in seed and pulses are the high-starch, high-protein version of grain legumes, the researchers wanted to screen faba beans for high growth and high yield.
“Because of this better growth, we would expect greater amounts of nitrogen acquired by the legume crop,” Bueckert says. “This means that growers could pick a crop with good biological nitrogen fixation, avoid fertilizer nitrogen application, get a reasonably good yield, and still have sufficient nitrogen in the stubble and old root system to supply a succeeding crop with more nitrogen.”
Researchers sampled plants from the faba bean breeding program, led by Dr. Bert Vandenberg at the Crop Development Centre at the U of S. Genetic material covered a range of countries and breeding programs, but most of the material was suited to Western Canada.
They independently tested three statistical approaches to relate between two and 10 amino acids to crop growth (biomass), yield, plant nitrogen content, and the amount of plant nitrogen that came from biological nitrogen fixation only.
“At the end, we had a nice tool to use for field screening so we could measure thousands of plants from nursery or breeding material, without having to generate field plots with reference crops. We can sample as early as flowering,” Bueckert says. “We can pick out two of the best white flowered genotypes, and three of the best coloured flowered genotypes, when the target is selecting the top five out of 30 genotypes/varieties.”
With the upgrade in the sampling infrastructure anticipated this year, the researchers will be able to put their research to work and seek out the best from nurseries and breeding material to bring better nitrogen fixing faba beans to farmer’s fields.
“It is all about balance, having a high-yielding protein crop that is attractive for farm production along with a quality protein yield that is commercially lucrative,” Bueckert says. “At the same time, if we are too greedy and put all the plant nitrogen into grain, we end up with less or minimal nitrogen in stubble and roots, so less is left to supply the next rotation.”
SPG Investment: $93,725
Project Length: 3 years
Co-Funder: Agriculture Development Fund - $90,000
Project Lead: Dr. Rosalind Bueckert - Professor of Plant Sciences, University of Saskatchewan