Effect of the Gpc-B1 Gene On Grain Protein Concentration in Hard Winter Wheat (Triticum aestivum L.) in the Pacific Northwest of the US.

Grain protein concentration (GPC) influences end-use quality of products made from wheat (Triticum aestivum L.); therefore, this trait is commonly a high priority for breeders.  However, most variation in GPC is due to variability in the environment, instead of genetics effects.  In addition, GPC and grain yield are negatively correlated.  Due to the negative correlation between yield and GPC, and the high variation caused by the environment,  enhancing genetic  expression of this trait will be important to improving grain protein concentration in hard wheat varieties.  Previous studies have shown varying results in spring wheat in regards to increasing GPC, with some studies increasing GPC by up to 1.5%.  The objective of this study was to evaluate the Gpc-B1 gene in hard winter wheat cultivars.  Near-isogenic lines (NIL) with and without the Gpc-B1 gene were created in three populations: Lassik by Farnum, Lassik by WA8161 (an advanced breeding line), and Farnum by Eddy.  Presence of this gene was validated using the diagnostic marker Xucw89.  Field trials were planted in Pullman and Lind, Washington under a randomized complete block design which included NIL and check cultivars with and without the Gpc-B1 gene. These two locations differ by annual rainfall averages and yield potential.  Results will be presented on the effect of the introgression of the Gpc-B1 gene on hard winter wheat cultivars in the Pacific Northwest region of the US.  Preliminary data indicate that the presence of the Gpc-B1 gene increases GPC in hard winter wheat.  This data will be useful to wheat breeders developing hard winter wheat cultivars with high grain protein content.