Research CEREAL CROPS that fix their own nitrogen? Achieving this dream could result in major benefits for agriculture and the environment. Scientists around the world are pursuing this goal, including a group in Alberta. The Lethbridge-based researchers have already made impressive advances towards developing nitrogen-fixing triticale plants as a first step to creating other nitrogen-fixing cereals. “The idea of nitrogen-fixing cereals is not new. The discovery in the late 1880s of symbiosis between nitrogen-fixing bacteria and legumes spurred the eventual question of whether it is possible in non-legume plants, including cereals. However, the path from the idea to its successful realization is in this case quite bumpy,” says Dr. Alicja Ziemienowicz, a research biologist with Agriculture and Agri-Food Canada (AAFC) and an adjunct professor at the University of Lethbridge. She is co-leading this nitrogen fixation research with her AAFC colleague Dr. François Eudes. “There are three biotechnological approaches for biological nitrogen fixation in cereals, and all require genetic engineering of bacteria or plants or both,” she explains. “The first one is to create rhizobium-legume-like symbiosis in cereals; in other words, to convince rhizobia and cereals to form an interaction similar to the interaction of rhizobia with legumes. The second approach aims at improving bacteria that live inside cereal plants or in the soil right next to cereal roots so these bacteria can perform nitrogen fixation more efficiently.” However, these two strategies would rely on the use of bio- fertilizer inoculants, which are not always as effective as crop growers would like and are not as convenient as having the trait in the seed. “When I joined the team of Dr. François Eudes at AAFC’s Lethbridge Research and Development Centre about five years ago, we decided to take the third approach to the biotechnological solutions for the nitrogen fixation problem,” adds Ziemienowicz. “This approach is perhaps the most challenging one but also the most promising. It involves the direct transfer of bacterial nitrogen fixation (nif) genes into the plant.” Ziemienowicz is an expert in this type of research and has been working on development of better technologies for plant improvement for over 20 years. She is excited to be applying her knowledge and skills to nitrogen fixation in cereals “to achieve practical and applicable outcomes in a research area that is so important for Canadian and global agriculture.” “Many have labelled nitrogen-fixing cereal crops as the ‘holy grail,’” notes Lauren Comin, research manager with the Alberta Wheat Commission (AWC). “Nitrogen-fixing cereals could bring a lot of significant benefits. First of all is the benefit to the farmer’s profit. Obviously producers would save money by reducing input costs, and there could be time savings as well. Those benefits alone are enough for us to get excited.” Ziemienowicz states, “Nitrogen fertilizers contribute about 20 per cent of cereal crop production costs, not including costs of fertilizer application: fuel, machinery, labour. Cereal crops capable of fixing nitrogen for their own needs will reduce crop dependence on nitrogen fertilizers, and will increase their performance and productivity in nitrogen-deficient soils.” Both Comin and Ziemienowicz point out that nitrogen-fixing cereals would also contribute to sustainability. “There is an ever- growing interest in sustainability from those on the farm and off the farm. Plants that could fix all or some of their nitrogen would mean fewer synthetic applications, less nitrogen loss to the atmosphere and less leaching into the waterways,” says Comin. Ziemienowicz explains that not all of the applied fertilizer is actually used by the crop, and the unused portion can cause Alberta researchers are making exciting progress in this challenging task. On the Way to Nitrogen-Fixing Cereals These triticale plantlets were developed from microspores carrying a selectable marker gene used in the AAFC nif cluster. Photos: Alicja Ziemienowicz, AAFC 10 www.seed.ab.ca | Advancing Seed in Alberta