Marker-Assisted Breeding for Improvement of Fusarium Head Blight Resistance in Spring Wheat.

Fusarium head blight (FHB) is a serious global problem for wheat producers, handlers and end-users around the world. FHB rescues grain yield, and enduse quality. In addition, a mycotoxin, deoxynivalenol (DON) associated with the disease can render the grain unsuitable for human and animal consumption at a levels as low as one ppm. The objective of this research was to develop a white seeded spring wheat variety with a high level of FHB resistance using marker-assisted selection (MAS). Snowbird, a FHB susceptible hard white seeded wheat was crossed to Sumai3, a Chinese cultivar with high level of FHB resistance, as the female parent. Twenty thousand F₂ plants were grown in the greenhouse. One thousand and five hundred white seeds were visually selected from the F₂ population. This population was advanced to F₅ by single seed descent. At the seedling stage of F₅, MAS was performed for three FHB QTLs on chromosomes 3B, 5A, and 6B, respectively. Two hundred and fifty F₅ lines were selected with two or three resistance QTLs and screened in a FHB disease nursery in 2008. Fifteen F₆ lines were selected based on FHB resistance and agronomic performance.  Seed of the 15 lines was increased in the greenhouse in the winter of 2009. These 15 lines and two parents Sumai3 and Snowbird, plus AC Vista as a check were evaluated in the AAFC-Ottawa FHB nursery and yield tested over three years (2009-2011). The 15 lines had either 2 or 3 of the FHB QTLs and DON levels for the 15 lines ranged from 1.5 ppm to 9.4 ppm whereas, DON levels in the parents ranged from 1.7 to 17.6 ppm. Grain yields of the 15 lines were higher than Sumai3 and most of 15 lines were earlier maturating than Sumai3. The enduse quality of the lines was significantly improved over Sumai3, based on the Glutomatic test. Lines WS-886 and WS-175 are currently being used in a spring wheat backcross breeding program for development of hard white wheat with FHB resistance.