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2008 U of M Research Special Report - University of Minnesota Small Grains Research Initiative Update
For More Information For more information about the Small Grains Research Initiative: This report prepared by the Minnesota Wheat Research and Promotion Council and the Minnesota Association of Wheat Growers in cooperation with the University of Minnesota. Accelerated Breeding of Disease Resistant Wheat The objectives of accelerated breeding of disease resistant wheat at the University of Minnesota are:
The spring wheat MN01311-A-1, pedigree 97T-1003 (Verde/Sonja)/Verde, was released as ‘Tom’ in 2008. Tom has medium maturity, height, and straw strength (Table 1). Tom has shown consistently high grain yields, especially in northern locations, moderate leaf rust resistance, and Fusarium head blight (FHB, scab) resistance comparable to Alsen. Tom is moderately resistant to the Ug99 race of stem rust. Tom has large kernels, above average test weight and grain protein content, and very good resistance to preharvest sprouting. The name ‘Tom’ was chosen to honor the contributions to the wheat industry of Tom Anderson, who passed away in 2007. Tom Anderson was a visionary leader for agriculture at the local, regional, and national levels. Tom farmed near Barnesville, MN, served as co-chair of the U.S. Wheat and Barley Scab Initiative and as a grower representative on numerous research and search committees. Data from the last three years have indicated that U of MN releases and variety candidates have improved levels of FHB resistance (Table 2). Our project continues to identify other lines with high levels of FHB resistance. Out of 48 entries (representing 8 breeding programs) in a regional FHB nursery, the three with the lowest vomitoxin were U of MN experimental lines. Unfortunately, these highly resistant lines have other characteristics that make them undesirable variety candidates, such as low yield, excessive height, or weak straw. Nevertheless, they are used as parents by our program and others in the region as we continue to incorporate the highest levels of FHB resistance into agronomically acceptable varieties. During 2007, FHB nurseries were established at Crookston, Morris, and St. Paul. These nurseries were inoculated and misted to enhance disease and involve collaboration with agronomists at Crookston and Morris, and personnel from the Plant Pathology Department. Similar to 2006, the nursery at Crookston produced excellent data, but FHB levels were low in the Morris and St. Paul FHB nurseries, probably due to continually high temperatures. More than 2,000 wheat lines were characterized for their FHB resistance in the Crooktson nursery. FHB resistance ratings of named varieties were reported in Prairie Grains magazine, Minnesota Varietal Trials Results, the 2007 Prairie Grains Conference and summer field day at Crookston. We use marker-assisted selection for enrichment of early generation populations and parental characterization. Marker -assisted selection helps us select plants that have desirable gene combinations. We routinely use markers to screen for genes that provide resistance to Fusarium head blight (Fig. 1), leaf rust, and tan spot. In cooperation with the USDA-ARS Genotyping Center in Fargo and funded jointly by this project, the U.S. Wheat and Barley Scab Initiative, and the USDA-CSREES WheatCAP project, we collected about 24,000 marker data points from 8,000 samples in 2007. We screen all of our crossing parents with markers for about a dozen important genes. This screening reveals which of our varieties and elite breeding materials contained important genes, thereby directing future DNA marker screening of crosses and helping us decide which crosses to make (and not to make) to be sure that the resulting progeny contain all the desired genes. Table 1. Agronomic characteristics and grain quality of recent U of MN varieties and one experimental line.
Table 2. Preharvest sprouting and disease rating, and relative grain yield of recent U of MN varieties and one experimental line.
Figure 1.
DNA marker profile of Fhb1, a gene that contributes resistance to Fusarium head blight. This marker is used to select plants containing this gene, prior to field-based testing. -- Dr. James A. Anderson, University of Minnesota wheat breeder. |
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During 2007, undergraduate research assistants
rate plots of wheat plants for foliar diseases. Such tests are conducted annually by the NWROC Extension Plant Pathology Program which is headed by Dr. Charla Hollingsworth.