Genetic and Environmental Variation in β‐Glucan Content and Quality Parameters of Barley for Food

Abstract

High p-glucan content is desirable in barley (Hordeum vulgare L.) for many food uses. The effects of environment, head type, and starch-hull type on total p-glucan and protein content, extract viscosity, and seed color in barley were tested. Barley cultivars varying in head (two row and six row), starch (normal, waxy, high-amylose, and fractured), and hull (covered and hull-less) phenotypes were grown in single-row plots at one location front 1989 to 1991. Higher mean P-glucan content and extract viscosity occurred in 1989, a lowmoisture, hot year. Cultivars with the two-row and six-row head type did not differ for any of the traits analyzed. Waxy hull-less cultivars had the highest mean p-glucan content (69.3 g/kg) and extract viscosity (29.1 cP) compared with the normal covered cultivars (38.0 g/kg and 4.6 cP, respectively). Single degree-of-freedom contrasts found differences between normal starch and waxy starch isotypes consistent among the background genotypes ('AzhuP, 'Betzes', 'Bowman', 'Robust'). Dietary fiber analysis of selected samples grown in 1990 found the highest soluble fiber content in cultivars having waxy or high amylose starch and hull-less seed. In a separate experiment, 'Wanubet', a waxy hull-less cultivar, was grown in 42 commercial fields from 1989 to 1991. p-Glucan content varied from 45.5 to 94.6 g/kg, extract viscosity from 8.9 to 108.2 cP, and protein content from 98.0 to 186.0 g/kg. Seed color varied but was unrelated to these components. The significant effect of environment on all of the characteristics indicates the need for food barley quality standards and tests.

Effects of cropping system and genotype on variability in important phytonutrients kontent of the barley grain for direct food use

“…In our case, however, it was not unambiguously true of the hulless waxy barleys -though on average they had a little lower starch content, the differences from the malting and some hulless materials were not significant. Fastnaught et al (1996) reported that the waxy types of barley had the most beta-glucans (6.93% vs. 3.8% in standard varieties), which was also confirmed by our results. On average, the waxy varieties had 4.75% beta-glucans in grains and thus differed significantly from the varieties with standard starch (4.12%).…”

“…Perez-Vendrell et al (1996) found out that the variety and locality and year had a statistically significant effect on the content of beta-glucans in the caryopses of standard, spring and winter varieties. According to these authors (Fastnaught et al 1996) a higher beta-glucan content was also in relation with the effect of year -heat and drought induced a higher content. This finding can be confirmed by our results as well because the lowest mean content of beta-glucans was measured in the extremely wet and cold weather in 1997, especially in the period of grain formation in the months of June and July (Figure 1a).…”

The Genetics and Transcriptional Profiles of the Cellulose Synthase-Like HvCslF Gene Family in Barley

“…This possibility is exemplified by the observation that one starch branching isoenzyme (SBEII) makes up only 2% of the total SBE enzymes in potato (Solanum tuberosum) tubers, but has a major effect on amylose content (Jobling et al, 1999). It has also been reported that the (1,3;1,4)-b-Dglucan content of barley grain is affected in large degree by environmental factors, in particular by dry conditions toward the end of grain maturation (Fastnaught et al, 1996;Hang et al, 2007). In contrast to the situation with barley HvCesA genes, which appear to be cotranscribed to form enzyme complexes that might consist of three different HvCesA isoenzymes (Burton et al, 2004), at this stage we have not been able to detect any correlations in the transcript levels of different HvCslF genes.…”

β-GLUCANS CONTENT AS A PERSPECTIVE TRAIT IN THE BARLEY BREEDING FOR FOODSTUFF USE (review)

“…E f f e c t s o f g e n o t y p e a n d e n v i r o n m e n t o n  -g l u c a n c o nt e n t i n g r a i n . -Glucan content in grain is largely determined by the genotype and climatic conditions of plant growth (55,(76)(77)(78)(79). Some researchers show that genetic factor has the largest contribution in variation of -glucan content (53,(80)(81)(82)(83)(84), while others assume the crucial importance of environmental conditions (77,85,86).…”

“…Along with it, C.E. Fastnaught et al (77) found that conditions of growing notably affect contents of starch, -glucans, and protein in barley grain, so they concluded the need for quality standards and tests for food barley.…”