No abstract

Facultative/winter six‐row malting barley is a distinct elite germplasm pool and a valuable resource that may prove useful in meeting the challenges of climate change. To preserve its diversity and make it accessible to the research and agricultural communities, the Oregon State University and University of Minnesota barley breeding programs are publicly releasing their winter/facultative six‐row malt advanced lines named the TCAP FAC‐WIN6 (MP‐1, NSL 512632 MAP), which also function as a genomewide association studies (GWAS) panel. The FAC‐WIN6 contains 296 lines—180 facultative and 116 winter—selected for disease resistance, malt quality, and general agronomic performance. To date, all lines have data for 6892 single nucleotide polymorphism (SNP) markers and phenotypic data from six experiments (representing 3 yr, eight locations), including traits such as malt quality, disease resistance, nitrogen use efficiency, and winter hardiness. The FAC‐WIN6 is one of 24 barley and wheat mapping panels and populations from the USDA‐ARS Triticeae Coordinated Agricultural Project (TCAP). As such, all of the TCAP FAC‐WIN6 genotypic and phenotypic data can be freely downloaded from the TCAP's online database, T3 (http://triticeaetoolbox.org/barley/). Preliminary GWAS have identified novel loci for wort β‐glucan, low temperature tolerance, and disease resistance. Given these results, the FAC‐WIN6 is a singular resource both for future winter six‐row barley breeding and for identifying and deploying genes for key barley traits in all backgrounds.

The Genome-Wide Association Studies approach was used to detect Quantitative Trait Loci associated with tocochromanol concentrations using a panel of 1,466 barley accessions. All major tocochromanol types- α-, β-, δ-, γ-tocopherol and tocotrienol- were assayed. We found 13 single nucleotide polymorphisms associated with the concentration of one or more of these tocochromanol forms in barley, seven of which were within 2 cM of sequences homologous to cloned genes associated with tocochromanol production in barley and/or other plants. These associations confirmed a prior report based on bi-parental QTL mapping. This knowledge will aid future efforts to better understand the role of tocochromanols in barley, with specific reference to abiotic stress resistance. It will also be useful in developing barley varieties with higher tocochromanol concentrations, although at current recommended daily consumption amounts, barley would not be an effective sole source of vitamin E. However, it could be an important contributor in the context of whole grains in a balanced diet.

Successful exotic plant invasions are likely to be caused by multiple, non-mutually exclusive mechanisms, and it is exceptionally difficult to weight the relative importance of these mechanisms identified in different experiments. To this end we used individual-based models to explore how integrating empirical results from experiments might help to elucidate the relative importance of seed origin, biogeographic differences in competitive outcomes, and disturbance in exotic plant invasion. We integrated results from (1) competition experiments between Centaurea solstitialis derived from populations in the nonnative range (California), the native range (Spain), and co-occurring native species from both ranges, (2) seed production by Centaurea plants from the different ranges grown in a common-garden environment, and (3) responses to disturbance experiments with plants from different native and non-native ranges. Californian C. solstitialis reached slightly higher abundances than its Spanish counterparts in every scenario, mainly due to higher seed production of Californians than their Spanish conspecifics, indicating the potential importance of evolutionary changes in the non-native range. In the absence of disturbance, grass species native to Europe showed stronger competitive effects on C. solstitialis than grass species native to North America, suggesting that release from competition in the native range may have some explanatory power for successful C. solstitialis invasion. However, the intensity of competition depended on the disturbance regime used in models. When intense disturbance was incorporated into the model, C. solstitialis was favored, with plants from Californian seed sources reaching higher densities than plants from Spanish seed sources. Our results are consistent with the idea that disproportional positive responses to disturbance in California, relative to those in the invader's native range of Spain, may be an important factor in the dominance of C. solstitialis in its non-native ranges. It is not clear why disturbance would have more beneficial effects on the invader in its non-native range, but the powerful effects of disturbance appear to interact in subtle ways with biogeographic differences in evolutionary trends, competitive intensities, life histories, and reproductive rates.

Alba' (Reg. No. CV-355, PI 672535) is a winter, six-row barley (Hordeum vulgare L.) released by the Oregon Agricultural Experiment Station in 2012. The name Alba was chosen due to the bright and attractive appearance of the crop at maturity. In high rainfall environments, it has a notable yield advantage over check cultivars and maintains excellent test weight and kernel plumpness. These advantages are attributable in part to resistance to barley stripe rust (incited by Puccinia striiformis f. sp. hordei) and scald (incited by Rhynchosporium commune).The principal end-use of Alba grain is as feed, but it could also be used for food (after pearling). Preliminary tests show that it can also be successfully malted and used in craft brewing.