20 BREEDERS TAKE SEVERAL factors into consideration when developing a new wheat variety, such as yield, quality, standability, and disease tolerance. Each class of wheat grown has its own characteristics andmanagement requirements. Approximately 85 per cent of wheat planted in Ontario is fall planted while roughly 15 per cent is spring planted. Dr. Ljiljana Tamburic-Ilincic is a recognized wheat breeder by the Canadian Seed Growers Association (CSGA), she is the Ontario Cereal Crop Committee (OCCC) disease coordinator, and is a research scientist based at the University of Guelph Ridgetown Campus. She has a focus on creating new soft red wheat varieties for Ontario. When Tamburic-Ilincic embarks on the journey of breeding a new wheat variety it can take up to 10 years; however she hopes for it to be a bit shorter using double haploid technology to get homozygous (where an individual inherits the same alleles for a particular gene from both parents) lines sooner in perhaps six to seven years. “Choosing the right parents before the cross is probably the most important decision,” says Tamburic-Illinic. Yield, fusarium head blight (FHB) resistance, and quality are all important for the cross to have good potential, along with lodging and winter survival. When Tamburic-Illinic is thinking of parents she usually looks for a good adaptive yield for North America, wheat from other regions is also useful but usually the quality is not there — and then the cross would need to overcome this hinderance. In terms of breeding, a first cross will be created, and a progeny developed. For the first cross, one plant will be the female, and another the male. The pollen is taken from one plant to fertilize the other, and a paper bag is placed around the fertilized plant. The seed is then harvested. This is the F1 generation. The target is to have 100 lines from one cross as this gives a good opportunity to select promising looking plants. TamburicIllinic outlines that they don’t want plants that are too tall. They look for plants that have heading dates that work for Ontario, and good winter survival. All plants are planted outside, in small single rows. LATER STAGES In the later stages of testing, yield and 1,000 kernel weight come into play, usually in the fifth or sixth generation — or in the case of double haploid technology use, four years after the line has been developed. It is important to compare the new lines with what is currently available. The new potential line needs higher yields than the check and needs to be supported by the OCCC. Lines are evaluated for resistance to Powdery mildew, Septoria, and Rust (leaf, stem, and stripe). Tamburic-Illinic shared that usually Seed development: wheat BREEDING THE RIGHT CHARACTERISTICS Laura Ferrier leaf diseases can be controlled with a fungicide application but in being a breeder she needs to bring in resistance. Once there is a good package for leaf disease resistance, then the team can be more specific and look for quality and select progeny. They aim to roughly have 25 lines advance from the single cross which they will investigate further. In general, the aim is for a shorter straw plant with a high yield, however some farmers want straw so it is important to keep in mind if it checks all the other boxes and still is taller than it may advance. Tamburic-Illinic manages the FHB nursery in Ridgetown, where they inoculate wheat and screen for symptoms along with DON content in the grain. “Even if the line has a good yield, but is susceptible it will not be supported by the OCCC,” says TambuircIllinic. Through looking at more agronomics and quality, the aim is to get down to about 10 lines, which have advanced from a single cross. Selected lines will be tested in areas 1 (Ridgetown/Tupperville), 2 (Palmerston/ Elora), and 3 (Winchester/Ottawa). Once this process finishes, the wheat lines enter further testing and will then be planted from Ottawa to Harrow in 10 different locations. “At the end of the day, when we select lines, we don’t know where they might do the best. We are so lucky to have University of Guelph locations across the province where we can usually have trials in multiple locations to see how lines perform in different areas,” says Tambuirc-Illinic. TRIALS The wheat will then be placed in the OCCC performance trials. Once the variety has been approved by the OCCC and registered with the Canadian Food Research FIGURE 1. DEVELOPMENT OF DH WHEAT LINES. PHOTO COURTESY OF HTTPS://COLORADO WHEAT.ORG.
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