Abstract. The main objective of this study was to investigate the effects of genetics and environment on the proximate composition and non-starch polysaccharide levels in hulless barley. Ten hulless barley varieties were grown at ten different locations over a period of three years. Harrington was included as a hulled check variety. All 300 barley samples were analyzed for their proximate composition (moisture, protein, lipid, ash) as well as starch and non-starch polysachharides including -glucan, pentosans and soluble and insoluble dietary fiber contents. Analysis of variance evaluated the main effects of Variety, Location and Year and their interaction effects. The results showed a significant (P0.001) Variety effect on all variables studied when Harrington was included, but genetics did not have a significant effect on pentosan and insoluble fiber contents of hulless barley. Variety*Location effect was significant for ash, starch and pentosan, Variety*Year effect was significant for protein, lipid, -glucan, pentosan, insoluble and total fiber, while Location*Year effect was significant for all variables. When Harrington was excluded Variety*Year effect on protein and lipid was no longer significant. Correlation analysis indicated that yield was not correlated to any of the carbohydrate components and test weight and kernel weight were positively correlated to -glucan and starch levels. Thus, new barley varieties can be developed without any negative effect on agronomic parameters by selecting for these components, which is crucial for new value-added opportunities for barley.

Introduction. Hulless barley is a growing portion of the barley industry that has potential as a product in human food and nutrition. One of the components of barley identified by food scientists with the potential of nutritional benefits is -glucan. Several waxy barleys with high -glucan have been approved for registration in the last two years. However, the commercial production of these varieties has not had the level of expected beta-glucans (7%). This leads us to believe that the environment may have a more disproportionate role in the determination of -glucan content than previously thought. If we are to maximize the potential of developing hulless barleys for various value-added objectives we need to have a better understanding of the role the environment and production practices have on the constituent components of starch, proteins and non-starch polysaccharides.

The main objective of this study was to investigate the effects of genetics and environment on the proximate composition and non-starch polysaccharide levels in hulless barley. The project goals were:

1. to conduct proximate analysis of ten varieties of hulless barley grown at ten different locations over three years including moisture, fat, protein and ash contents;
2. to quantitate starch and non-starch polysaccharides that may have influence on human nutrition such as -glucan, pentosans and total, soluble and insoluble fiber; and
3. to determine the Genetics by Environment effects on the levels of these components in the barley grain.

Materials and Methods. Ten varieties were grown at ten locations of the Hulless Barley Coop test in 1993, 1994 and 1995 with Harrington as a hulled barley check. Barley varieties included in the study were Harrington, Condor, Falcon, CDC Richard, HB103, HB104, HB313, HB316, HB325, HB605, HB606, HB608 and HB803. HB313 and HB803 are waxy endosperm barleys. CDC Richard, Condor, HB325, HB605 and HB606 are two-row hulless and Falcon, HB103, HB104, and HB608 are six-row hulless. These varieties were grown at the following locations: Beaverlodge, Brandon, Calmar, Glenlea, Goodale, Irricana, Kernen, Lacombe, Lethbridge, Olds and Trochu. Yield, test weight and 1000 kernel weight data were recorded for each. All 300 barley samples were analyzed for their proximate composition (moisture, protein, lipid, ash) as well as starch and non-starch polysachharides including -glucan, pentosans and soluble and insoluble dietary fiber contents. Analysis of variance evaluated the main effects of Variety, Location and Year and their interaction effects.

Results and Discussion. The results showed a significant (P0.001) Variety effect on all variables studied when Harrington was included, but genetics did not have a significant effect on pentosan and insoluble fiber contents of hulless barley. Variety*Location effect was significant for ash, starch and pentosan, Variety*Year effect was significant for protein, lipid, -glucan, pentosan, insoluble and total fiber, while Location*Year effect was significant for all variables. When Harrington was excluded Variety*Year effect on protein and lipid was no longer significant. Correlation analysis indicated that yield was not correlated to any of the carbohydrate components and test weight and kernel weight were positively correlated to -glucan and starch levels. Thus, new barley varieties can be developed without any negative effect on agronomic parameters by selecting for these components, which is crucial for new value-added opportunities for barley.

Acknowledgements. Gratitude is expressed to Alberta Agricultural Research Institute – Matching Grants Program, Alberta Barley Commission and Alberta Wheat Pool for financial support, and Dr. Sam Jadhav and Mr. Arun Lekhi for technical assistance.