Submitted to: Crop Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 7/10/2008
Publication Date: 1/30/2009
Citation: Rey, J.I., Hayes, P.M., Petrie, S., Corey, A., Flowers, M., Ohm, J., Rhinhart, K., Ross, A. 2009. Potential for Production of Dryland Barley for Human Food: Quality and Agronomic Performance of Spring Habit Germplasm in Oregon. Crop Science 49:347-355 Interpretive Summary: The approval of the barley health claim by the FDA, coupled with the increasing health consciousness of an American public faced with alarming rates of obesity and coronary heart disease, may increase interest in, and markets for barley. To meet this demand, barley processors are likely to require production of waxy barley cultivars due to their high ß-glucan contents. However, our research indicates that there are significant production problems and yield reductions associated with the hulless waxy trait. Therefore, waxy, hulled lines such as Salute and BZ 502-563 are likely the best alternative for growers and processors. Mechanical removal of the hull is easily accomplished by pearling. Because ß-glucan levels are low in the hull and outer layers of the seed coat (Henry, 1987a), little value would be lost in this operation. Additionally, both Salute and BZ 502-563 show no production or yield differences when compared to Baronesse and Camas, the hulled, non-waxy lines that are most widely grown in the dryland production zones of the Pacific Northwest. Thus, spring cultivars currently exist that are agronomically competitive with current feed barleys and have high ß-glucan that could support a niche food barley market in the Pacific Northwest. Development of winter habit food barleys would provide growers and industry with even more choices.
Technical Abstract: Grain ß-glucan percentage is the most important attribute for barley (Hordeum vulgare L.) varieties destined for the human food market. This trait is important because of the cholesterol-reducing properties of ß-glucan. High levels of grain protein, test weight and seed size may also add value. Seed yield potential, in part, determines the economic feasibility of producing human food varieties. In order to determine the potential of food barley production in the dryland production areas of the Pacific Northwest of the U.S.A, 33 cultivars and advanced lines reported to vary in ß-glucan were grown in 2006 and 2007 at two locations in Oregon. Seed yield, test weight, percentage of plump kernels, grain ß-glucan and grain protein were measured on replicated samples from the four environments, allowing for assessment of average performance as well as genotype x environment interaction. Estimates of variance components showed that ~ 66% of the variability in ß-glucan content was attributable to genotype. Cultivars and lines with waxy starch showed the highest average ß-glucan values. We found significant two- and three-way interactions but these accounted for much less of the total variation in the measured phenotypes than the main effects of variety, year, and location. Hulless accessions were significantly lower yielding than hulled accessions, particularly in the second year of the study. Hulled, waxy starch varieties appear to have the greatest agronomic potential for dryland production as they combine high yield potential and grain ß-glucan percentage.