19 www.seed.ab.ca | fall.2018 varieties of bread wheat and durum wheat and determining which combination of acceleration methods is best for each cultivar. “We want to see if we can do any tailoring of conditions for particular varieties,” notes Rajagopalan. The third objective is to rapidly generate a recombinant inbred line population under accelerated growth conditions. Such lines are very useful for mapping traits in a plant’s genome. The lines generated in Rajagopalan’s project will be used in other projects to characterize resistance genes for rust diseases in wheat. “And the fourth objective is to evaluate long-term changes induced when plants are grown for multiple generations under accelerated growth conditions,” says Rajagopalan. “We want to see if any long-lasting effects are happening in the plants compared to plants grown under normal conditions.” Polowick adds, “One of the reasons we want to look at the long-term effects is because we are putting the plants under a lot of stress.” Breeders will want to be sure plants grown under induced stresses to accelerate their growth will respond to things like diseases and insect pests in the same way when they are grown under normal conditions. Boosting a Breeding Revolution This two-year project started in April 2017, and Rajagopalan’s team has already completed two of the objectives. “We have completed the testing of the effects of Fusarium and rust resistance in different varieties under normal and accelerated growth conditions. And we have completed the very large- scale study to understand the effects of accelerated growth conditions on various wheat varieties. So we have a really good understanding of what conditions work best for the multiple varieties of durum and bread wheat that we have tested.” The researchers are currently working on the other two objectives. The effects of the accelerated growth conditions are very impressive so far. “Right now, we are getting about five to six generations of wheat within a year using these conditions. For plants grown under normal conditions [in a greenhouse], you will get around two to three generations per year. So you can reduce the generation time of the plant by half by adopting these conditions," says Rajagopalan. There is already interest in applying speed breeding beyond Rajagopalan’s project. “I’m running a parallel study with a private breeding company using the same accelerated breeding ideas with some of their wheat lines,” Polowick explains. “This concept has been heavily adopted by the plant breeding industry in places like Australia, and we’re hoping that some of our work here will make it more available to the Canadian breeders so Canadian farmers can benefit from our progress.” Along with the benefit of bringing new varieties to the market sooner, Polowick points to a further advantage. “Some of the other projects within the NRC [and other agencies] use the modern ‘omics’ such as genomics and proteomics, and these technologies have enabled great progress in the identification of novel plant traits whether it is to fight diseases or to mitigate the effects of environmental stresses. So it’s not accelerated growth conditions in isolation; it’s accelerated growth in combination with a lot of the progress being made in other projects that will provide the most benefit to the farmers.” Alberta Wheat Commission research manager Lauren Comin sees value in this type of research. “Decreasing the time it takes for a variety to be developed is very important for producers. Producers need to be able to be nimble when it comes to choosing a variety. For example, resistance to abiotic and biotic stress plays an important role in selection. We are seeing pests adapt over time and currently employed resistance genes are being defeated. At the same time, we are seeing remarkable advancements in pre-breeding and discoveries of new sources of resistance. Shorter variety development times mean that new genes can be deployed and be in a farmer's field without too much of a lag. Our scientists can respond to changes more quickly, which allows farmers to adapt faster as well.” Along with the potential for large, rapid steps forward in Canadian wheat varietal improvement, other crops could also benefit from the powerful combination of accelerated breeding and valuable new traits. Australian research shows speed breeding can also work in such crops as barley, chickpea, pea and canola, with the number of possible generations per year depending on the crop type. “We would love to see wider adoption of these accelerated breeding methods that we are working on in Canadian wheat breeding programs and to also make progress in other crops where this approach is applicable,” Rajagopalan says. His project is funded by the Saskatchewan Ministry of Agriculture, the Canada-Saskatchewan Growing Forward 2 program, and the National Research Council of Canada. Carolyn King “Right now, we are getting about five to six generations of wheat within a year using these conditions. For plants grown under normal conditions [in a greenhouse], you will get around two to three generations per year.” —Dr. Kishore Rajagopalan