Registration of Zak ERA8 Soft White Spring Wheat Germplasm with Enhanced Response to ABA and Increased Seed Dormancy

Zak ERA8 (ENHANCED RESPONSE to ABA8) (Reg. No. GP-966, PI 669443) is a unique line derived from soft white spring wheat (Triticum aestivum L.) cultivar Zak that has increased seed dormancy but after-ripens within 10 to 16 wk. The goal in developing this germplasm was to use increased seed dormancy to improve tolerance to preharvest sprouting, a problem that can cause severe economic losses. This germplasm was developed by USDA-ARS, Pullman, WA, in collaboration with Washington State University. Zak ERA8 was tested under experimental number 60.1.27.10. The ERA8 mutation was generated by chemical mutagenesis followed by selection for the inability to germinate on abscisic acid (ABA) concentrations too low to inhibit wild-type Zak seed germination. The semidominant Zak ERA8 line has been backcrossed twice to wild-type Zak. Following the first backcross, Zak ERA8 showed similar morphological and grain quality traits to the original Zak cultivar.