Protein and hordein fraction content in barley seeds as affected by sowing date and their relations to malting quality

The effect of sowing date on grain protein, hordein fraction content and malting quality of two-rowed spring barley was investigated by using ten commercial cultivars with different grain protein content and the relationships among these traits were examined. The results showed that grain protein content and B hordein content increased as the sowing date postponed and were significantly affected by sowing date, while C and D hordein contents were less influenced by sowing date. There were significant differences in grain protein and hordein fraction content among the ten cultivars. The coefficient of variation of D hordein content was much larger than that of B and C hordein contents, suggesting its greater variation caused by different sowing dates. Beta-amylase activity and diastatic power were also significantly affected by sowing date, with malt extract being less affected. Significant differences in measured malt quality were found among the ten cultivars. Grain protein was significantly correlated with B hordein and malt extract positively and negatively, respectively. There was no significant correlation between beta-amylase activity or diastatic power and grain protein content. B hordein was negatively and significantly correlated with malt extract, but no significant correlations between C hordein, D hordein and malting quality traits.

Variation of Grain and Malt Qualities in Barley as Affected by Cultivars and Environments

Inferior and unstable quality of malt barley in China has limited its wide use in malting and brewing industries. In this research, eight two-rowed barley cultivars were planted at 7 locations with different ecological conditions in southern China, to investigate the cultivar and environmental effect on grain and malt qualities. The results showed that grain protein content differed dramatically among locations, but there were no significant differences among cultivars. For four malt qualities including diastatic power, wort viscosity, Kolbach index and malt extract, significant differences were found among cultivars and locations, except for diastatic power among cultivars. Coefficients of variance(CV)caused by location were greater than those caused by cultivar for each quality parameter, especially for diastatic power and Kolbach index, indicating the predominant influence of environment on malt quality. The analysis showed that grain protein content was positively related to diastatic power and wort viscosity, and negatively to malt extract. Kolbach index was positively related to malt extract, and negatively to diastatic power and wort viscosity. Diastatic power showed positive and negative correlation with wort viscosity and malt extract, respectively.

The influence of drought stress on malt quality traits of the wild and cultivated barleys

As a major abiotic stress,drought causes instability and deterioration of malt barley quality.There is distinct difference among barley cultivars in the responses of the main malt quality traits to drought stress.In the previous study,we identified some Tibetan wild barley accessions with relatively less change of malt quality traits under drought.In this study,we examined the impact of drought stress during grain filling stage on grain weight and several important malt quality traits,including total protein content,β-glucan content,limit dextrinase activity,β-amylase activity,and protein fractions in four barley genotypes(two Tibetan wild accessions and two cultivars).Drought treatment reduced grain weight,β-glucan content,and increased total protein content,β-amylase activity.These changes differed among barley genotypes and treatments,and are closely associated with grain filling process and kernel weight.All the results indicated Tibetan wild barley had great potential for developing drought tolerant barley cultivars.Relatively stable kernel weight or filling process under water stress should be highlighted in malt barley breeding in order to reduce the effect of water stress on malt barley quality.

Cultivar and Environmental Effects on p-glucanase Activity in Both Barley Grain and Malt and Its Function in β-glucan Degradation

Eight two-rowed barley cultivars were grown at seven locations in the southern winter-barley zone of China. Mean grainβ-glucanase activity ranged from 39.89 U kg-1 for Suyin2 to 49.75 U kg-1 for Xi-umai3 in 8 cultivars grown at 7 locations, and from 38. 74 U kg-1 in Zhengzhou to 57. 96 U kg-1 in Putian among 7 locations on an average of all cultivars. Correspondingly, mean malt β-glucanase activity of 8 cultivars ranged from 313.33 U kg-1 for ZAU3 to 489. 89 U kg-1 for Daner Barley, and of 7 locations from 330.40 U kg-1 in Yancheng to 418. 24 U kg-1 in Putian. There were significant differences among cultivars and locations in maltβ-glucanase activities. The locations showed much larger variation in maltβ-glucanase activities than cultivars. The reduction of total β-glucan content after malting varied in both cultivars and locations, with a mean of 78.31%. The analysis of correlations showed that maltβ-glucan content was significantly positively and negatively correlated with grain β-glucan content and malt β-glucanase activity, respectively, and malt β-glucanase activity was significantly positively correlated with grain β-glucanase activity.

Genotypic and environmental variation in barley limit dextrinase activity and its relation to malt quality

Variation in the limit dextrinase activity of barley malt, and the relationships between limit dextrinase activity and malt quality parameters were investigated using eight cultivars grown at seven diverse locations in China for two successive years. Limit dextrinase activity varied with genotype and location, with the levels ranging from 0.245 U/g to 0.980 U/g. The results showed that the variation in limit dextrinase activity was more attributable to the environment (location and year) than to the genotype. The response of limit dextrinase activity to the environment differed markedly among cultivars, and was reflected by large difference in coefficient of variation of cultivars across diverse locations. Regression analysis showed that limit dextrinase activity was negatively correlated with malt viscosity (r=?0.52, P<0.01), positively correlated with Kolbach index (r=0.38, P<0.01) and malt extract (r=0.30, P<0.05), but had no significant correlation with malt protein content and diastatic power.

Evaluation of Chlorophyll Content and Fluorescence Parameters as Indicators of Drought Tolerance in Barley

Drought is a major abiotic stress that severely affects food production worldwide. Agronomic and physiological traits associated with drought tolerance are suitable indicators for selection of drought tolerance genotypes to reduce the impact of water deficit on crop yield in breeding program. The objective of this study was to identify indicators related to drought tolerance through analysis of photosynthetic traits in barley （Hordeum vulgare L.）. These traits included chlorophyll content, initial fluorescence （Fo）, maximum primary yield of photochemistry of photosystem Ⅱ （Fv /Fo） and maximum quantum yield of photosystem Ⅱ （Fv/Fm）. Four genotypes （Tadmor, Arta, Morocco9-75 and WI2291） variable in drought tolerance were used to investigate the correlation between these traits and drought tolerance. The results reflected that all of these traits were affected negatively in the four genotypes at different levels of post-anthesis drought stress, but the decrease in drought tolerant genotypes was much less than that of drought sensitive genotypes. The results further revealed that the components of the photosynthetic apparatus could be damaged significantly in drought sensitive genotypes, while drought tolerant genotypes were relatively less affected. On the other hand, the values of chlorophyll content, Fo, Fv/Fo and Fv/Fm in drought tolerance genotypes were significantly higher than those in drought sensitive genotypes under drought stress. It was concluded that chlorophyll content, Fo, Fv/Fo and Fv/Fm could be considered as reliable indicators in screening barley germplasm for drought tolerance.

Alleviation of Al Toxicity in Barley by Addition of Calcium

The potential mechanism by which Ca alleviates Al toxicity was investigated in barley seedlings. It was found that 100 Al-alone treatment inhibited barley plant growth and thereby reduced shoot height and root length, and dry weights of root, shoot and leaf; promoted Al accumulation but inhibited Ca absorption in plant tissues; and induced an increase in the activities of superoxide dismutase （SOD）, catalase （CAT）, and peroxidase （POD） and in the level of lipid peroxidation （MDA content） in leaves. Except for the increase in Ca concentration in plant tissues, treatment with 0.5 mM Ca in the absence of Al had less effect on the above-mentioned parameters, compared with the control. Addition of Ca efficiently reduced Al toxicity, which is reflected by the promotion of plant growth, reduction in Al concentration and MDA content, increase in Ca concentration and in SOD, POD, and CAT activities compared with the Al-alone-treatment; with increase in Ca level （3.0 raM）, the ameliorative effect became more dominant. This indicated that the alleviation of aluminum toxicity in barley seedlings with Ca supplementation could be associated with less absorption of Al and the enhancement of the protective ability of the cell because of increased activity of the antioxidative enzyme.

Effects of Waterlogging on Photosynthesis and Antioxidant Enzyme Activities of Six Barley Genotypes with Different Waterlogging Tolerance

A field experiment was carried out to study genotypic difference in the effect of waterlogging on photosynthesis, chlorophyll content and antioxidative enzyme activities in barley. Waterlogging caused a rapid decline in net photosynthetic rate (Pn) and stomatal conductance (gs), and little change in chlorophyll content during early days of the treatment. A dramatic increase in malondialdehyde (MDA) content, superoxide dismutase (SOD) and peroxidase (POD) in waterlogged plants in the early days of the experiment was found, indicating the occurrence of oxidative stress in barley plants exposed to waterlogging. There was a highly significant difference in the changed extent of all these parameters among genotypes. Franklin and Yongjiahong Liuleng Damai, which were relatively sensitive to waterlogging in terms of growth, photosynthesis and chlorophyll content, accumulated much more MDA than the other two relatively tolerant genotypes (93-3143 and QS). After removal of waterlogging, the genotypic difference became much greater in recovering of these examined parameters. Yongjiahong Liuleng Damai showed higher recovery, while Franklin only recovered to 50% of the control at the 14 day after waterlogging removal. It may be concluded that it is the difference in anti-oxidative stress caused by waterlogging that account for the major difference in photosynthesis among barley genotypes.

Genotypic and Environmental Variations of Arabinoxylan Content and Endoxylanase Activity in Barley Grains

Arabinoxylan （AX） content in barley grains is an important quality determinant when barley is used as raw material of malt or beer production. The cultivar and environmental variations of total arabinoxylan （TAX）, water extractable arabinoxylan （WEAX） and endoxylanase activity （EA） were investigated using eight barley cultivars growing at seven locations with diverse environmental conditions. The results showed that both barley cultivar and location significantly affected the TAX, WEAX and EA levels, but the variations of TAX content and EA were mainly attributed to cultivar, while the impact of location on WEAX content was greater than that of cultivar. Correlation analysis indicated that TAX was significantly correlated to WUAX.

Genotypic Difference in Plant Growth and Mineral Composition in Barley Under Aluminum Stress

Four barley genotypes (Tiantaiyangdamai, Xiyin2, Mimaill4 and Tai94-Ce6) were exposed to 0, 50, 100, and 150μM of Al-containing solution with pH 4.5, to determine the differences in growth inhibition , Al concentration and accumulation and mineral composition among genotypes. The results showed that Mimaill4 and Tai94-Ce6 had significantly higher Al concentration and accumulation than Tiantaiyangdami and Xiyin2, especially in roots, and the growth traits including root and shoot dry weights, shoot height, root length and tillers per plant were more inhibited in the former two genotypes. Al treatments caused a significant reduction of N, P, K, Ca, Mg and Mn content in both roots and shoots, of Cu in shoots; and a significant increase in Fe and Zn content in both roots and shoots, of Cu in roots. The changed rates of mineral content caused by Al treatments, in terms of the content in 150μM Al divided by the content in the control, differed significantly among four genotypes. Two Al-sensitive genotypes, Mimaill4 and Tai94-Ce6 had much greater changes in mineral content than other two Al-tolerant genotypes Tiantaiyangdamai and Xiyin2 when subjected to Al stress in comparison with the control. It is indicated that the Al-tolerant genotype is characterized by less uptake and accumulation of Al in roots and smaller disorders in mineral metabolism and ion homeostasis.

Relationship of Grain Fructan Content to Degree of Polymerisation in Different Barleys

Fructans are important in the survival of plants and also valuable for humans as potentially health promoting food ingredients. In this study fructan content and composition were determined in grains of 20 barley breeding lines and cultivars with a wide variation in chemical composition, morphology and country of origin, grown at one site in Chile. There was significant genotypic variation in grain fructan content ranging from 0.9% to 4.2% of grain dry weight. Fructan degree of polymerisation (DP) was analysed using high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD). Changes in the distribution of different chain lengths and the pattern of structures of fructan were detected with increasing amount of fructan in the different barleys. A positive correlation was found between fructan content and the relative amount of long chain fructan (DP > 9) (r = 0.54, p = 0.021). Our results provide a basis for selecting promising barley lines and cultivars for further research on fructan in barley breeding with the aim to produce healthy food products.

Assessing the product quality and biological activities of barley(Hordeum vulgare L.)grasses at different harvest times

Barley(Hordeum vulgare L.)grasses(BG)have attracted considerable interest due to their multiple physiological activities and health benefits.In this paper,eight BG at four different growth stages were collected:seedling,tillering,stem elongation,and heading,and their product qualities and biological activities were examined and studied.Results demonstrated that harvest time obviously influenced proximate composition,surface color,and amino acid profile.Z21 and Z23 harvested at the seedling and early tillering stages,respectively,had higher total phenolic content(TPC)and total flavonoid content(TFC)than the other BG.Moreover,Z21 and Z23 possessed better DPPH radical-scavenging ability,antioxidant capacity,andα-glucosidase inhibitory activity,which were positively correlated with TPC,TFC,and protein and total amino acid contents.Our findings suggested that the early tillering stages were the preferable harvest times for BG with good product quality and biological properties.

GREEN PLANT REGENERATION FROM PROTO PLASTS OF BARLEY (Hordeum vulgate L.)

Barley is the world’s fourth leading cereal in acreage planted, after wheat, rice and corn. Nevertheless, whilst plant regenerations from protoplast cultures of rice, corn and wheat were realized one after another during the past few years, only albinos were regenerated sporadically from barley protoplasts. The present note reports that a group of complete green plants has been obtained from protoplasts isolated from cell suspension cultures in barley.

大麦芽的化学成分

目的研究大麦芽的化学成分。方法通过乙醇提取、反复柱色谱、重结晶等分离纯化手段分离纯化了麦芽中的化学成分,并应用UV、MS、NMR等波谱解析和化学方法确定其结构。结果从生麦芽中分离得到6个化合物,分别鉴定为Nbenzoylphenylalanine2benzoylamino3phenylpropylester(1)、豆甾5烯3β醇7酮(2)、5羟甲基糠醛(3)、麦黄酮(4)、β谷甾醇(5)和胡萝卜苷(6)。结论以上所有的化合物均首次从中药麦芽中分离得到;1为首次从该属植物中分离得到。

氮肥运筹对大麦β-葡聚糖酶活性和麦芽品质的影响

研究了同一施氮水平下 3种氮肥运筹对大麦 β 葡聚糖酶活性和麦芽品质的影响。籽粒蛋白质含量 ,追肥孕穗期一次施用的处理 (N3)显著高于二叶期一次施用处理 (N1 )和二叶期与孕穗期分次等量施用处理 (N2 ) ,且品种间表现不同 ,N2 和N3处理之间 ,秀麦 3号无显著差异 ,而 92 1 1差异显著 ;氮肥处理对籽粒 β 葡聚糖含量的影响也表现为因品种而异 ,秀麦 3号 3种氮肥处理之间无显著差异 ,而 92 1 1则N2 处理显著高于其他两种处理 ;麦芽 β 葡聚糖酶活性两品种均以N2 处理最高 ,其中秀麦 3号显著高于其他两处理 ,92 1 1显著高于N1 处理 ,但与N3的差异不显著。制麦芽后 ,麦芽β 葡聚糖含量显著降低 ,且降低幅度因氮肥处理与品种而异 ,两品种均以N2 处理的降幅最大 ,品种之间则以秀麦 3号降幅显著大于 92 1 1 ,说明麦芽 β 葡聚糖酶活性在决定麦芽 β 葡聚糖含量上比籽粒 β 葡聚糖含量起有更大的作用。氮肥运筹对几个麦芽品质也有显著影响 ,N3处理的麦芽浸出率和库尔巴哈值显著低于N1 和N2 处理 。

施氮水平对啤酒大麦植株氮素吸收与利用及籽粒蛋白质积累和产量的影响

2004—2006年连续两个生长季,以苏啤3和单2两个啤酒大麦品种为材料,探讨施纯氮0、75、150、225和300kghm-2条件下,啤酒大麦氮素积累和转运、氮素利用及籽粒产量和蛋白质积累的特性。在0～225kghm-2施氮量范围内,啤酒大麦花前植株氮素积累量和转运量均随施氮水平的提高呈上升趋势,但施氮量提高至300kghm-2后,提高幅度变小;而花前氮素转运效率及其对籽粒氮的贡献率则均随施氮水平提高呈单峰曲线变化。籽粒谷氨酰胺合成酶和谷-丙转氨酶活性也随着施氮水平的提高而上升,促进蛋白质积累,提高籽粒蛋白质含量,而当施氮量低于197kghm-2时籽粒蛋白质含量才低于12%,符合啤酒大麦酿造要求。经回归分析,在施氮量为241kghm-2时产量最高。此外,氮肥回收效率以225kghm-2施氮处理为最高,氮素生理利用效率和氮收获指数随施氮量增加而显著降低。综合考虑各项指标,建议在类似本试验条件的啤酒大麦生产区,施氮量以150～197kghm-2为宜。

73份优异啤酒大麦种质资源主要麦芽品质性状的评价

以73份国内外啤用大麦种质资源为材料,分析了5个主要麦芽品质指标(麦芽浸出率、糖化力、α-氨基氮、库尔巴哈值、蛋白质)的遗传多样性及其相关。结果表明,73份大麦基因型麦芽品质性状间具有不同程度的变异,不同大麦基因型的5个主要品质指标均具有很高的遗传多样性指数,且5个品质性状之间存在不同程度的复杂相关。动态聚类分析将73份大麦基因型分成3类,不同类型分别适合于不同用途。研究结果可为啤酒大麦种质资源的多元化利用提供基础。

施氮水平对啤酒大麦氮素吸收、转运及籽粒蛋白质含量的影响

以苏啤3号和单2两个啤酒大麦品种为材料,研究了施氮量0 kg/hm2、75 kg/hm2、150 kg/hm2、225kg/hm2、300 kg/hm2对大麦氮素累积、转运,氮肥利用率及籽粒蛋白质积累特性的影响.结果表明,施用氮肥可显著提高不同时期叶片、茎秆中氮的含量以及籽粒中蛋白质含量;在施氮量0～ 225 kg/hm2时,啤酒大麦花前植株氮素积累量和转运量均随施氮水平的提高呈上升趋势,但施氮量提高至300 kg/hm2后,上升幅度变小;氮素转运效率和转运氮对籽粒氮的贡献率都随施氮水平的提高呈先增大后减小趋势,营养器官转运氮对籽粒氮的贡献率在59.24％至68.23％之间,本试验条件下,啤酒大麦的合理施氮量应控制在150～ 225 kg/hm2.

SSR多态性信息含量(PIC)对大麦糖化力的选择效果

通过检测103份贵州地方栽培大麦(Hordeum vulgare L.)的糖化力和麦芽无水浸提率,并在此基础上选择22对麦芽品质紧密连锁的SSR引物进行遗传标记。不同糖化力群体的引物多态性信息含量(polymorphism information content,PIC)的分析结果表明,与低糖化力群体相比,高糖化力种群具有丰富的谱带信息和更高的PIC参数(包括平均等位位点数、PIC平均值、PIC值大于0.5的比例和PIC值大于0.5的平均等位位点数),表明大麦的高糖化力可能与数量性状的基因加性效应有关,也提示了麦芽品质紧密连锁的SSR位点可作为大麦糖化力分子辅助选择(marker assisted selection,MAS)的候选指标。

贵州野生大麦麦芽品质性状的SSR标记分析

采用6对啤酒大麦的麦芽浸提和糖化力紧密连锁引物对103份采自贵州的野生大麦材料进行SSR标记。结果表明,贵州野生大麦麦芽品质性状存在丰富的变异,6对SSR引物共检测出38个等位变异,每个位点平均6.33个等位变异,其中GMS001位点对贵州野生大麦基因组DNA变异检测最有效。UPGMA聚类图显示,该6对与麦芽品质紧密连锁的SSR引物对区分野生大麦在贵州不同的资源产地和棱性是有效的,表现为遵义地区野生大麦遗传多样性丰富,而来自贵州凯里地区的野生大麦资源遗传多样性狭窄。麦芽品质性状标记结果表明贵州野生六棱大麦较四棱大麦的遗传差异更显著,表明进行贵州啤酒大麦人工育种的亲本应在亲缘关系较远的六棱大麦之间选择。