Registration of ‘USDA‐Basin’ and ‘USDA‐Wasatch’ bluebunch wheatgrass, originating from and adapted to the Central Great Basin of the western USA

Abstract The USDA‐ARS and Utah Division of Wildlife Resources announce the release of bluebunch wheatgrass [ Pseudoroegneria spicata (Pursh.) A. Löve.] cultivars ‘USDA‐Basin’ (Reg. no. CV‐35, PI 708099) and ‘USDA‐Wasatch’ (Reg. no. CV‐36, PI 708100) (experimental designations: Basin/Basin‐STZ4 and Wasatch/Basin‐STZ3a, respectively) for their seedling drought tolerance and establishment, and as the first bluebunch wheatgrass cultivars that geographically and genetically originate from the Great Basin region of the United States. Though regionally sourced materials are desired, most bluebunch wheatgrass used for re‐seeding this region originate in the Columbia Plateau and Blue Mountains of eastern Washington state. Therefore, bluebunch wheatgrass was collected from the Great Basin and evaluated for relative fitness. Four collections from within each of two phylogeographic groups were selected and crossed to form USDA‐Basin and USDA‐Wasatch. Genotyping and morphological measurements demonstrated that USDA‐Basin and USDA‐Wasatch are significantly ( P < 0.05) different from each other and four check cultivars. In response to drought, seedling root growth for both was greater ( P < 0.05) than ‘Columbia’ and ‘P‐7’, but similar to ( P > 0.05) ‘Anatone’, whereas they had lesser ( P < 0.05) specific leaf area than checks, indicative of enhanced seedling drought tolerance. USDA‐Basin and USDA‐Wasatch were similar ( P > 0.05) to each other and Anatone for stand establishment (mean of 38%), and both had greater ( P < 0.05) establishment at two of three sites than Columbia and ‘Goldar’. USDA‐Basin and USDA‐Wasatch originate from two seed transfer zones that compose 65% of reseeding efforts within the Central Great Basin and thus contribute important regional components to restoration projects in this region.