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181.
Prez-Vendrell A. M. Brufau J. Molina-Cano J. L. Francesch M. Guasch J. 《Journal of Cereal Science》1996,23(3)
The acid extract viscosities and β-glucan contents of ten two- and six-rowed barley cultivars grown at seven locations in three consecutive years in Spain were studied in the present work. The viscosities varied from 2·4 to 24·8 centistokes (cSt) and the mean value was 6·4 cSt. The average β-glucan content of barleys determined by HPLC was 3·5% with a range of 1·9–5·5%. Significant differences were found in both β-glucan content and acid extract viscosity between different cultivars, locations and years. The β-glucan contents and viscosities of winter cultivars were higher than those of spring. Cvs. Barbarrosa and Hatif de Grignon were the genotypes with the highest values for both parameters, while cv. Beka had the lowest viscosity and β-glucan content. Environmental factors influenced both parameters. The acid extract viscosities of barleys were correlated negatively with the amount of precipitation (r=−0·754;P<0·05). Barleys grown in wet and rainy areas (Girona and La Coruña) had lower viscosity values. 相似文献
182.
Barley (Hordeum vulgare L.) grain germination is required to perform the malting process. Maintenance of barley seed viability during storage is crucial for the malt industry; and modern cultivars are bred for rapid grain dormancy release after physiological maturity. Low dormancy level combined with rain close to harvest induces pre-germination/pre-harvest sprouting damage. Pre-germination might not affect viability in the short term after harvest, but it could reduce potential longevity (Ki) of a barley seed lot. Ki value is inherent for each barley lot; however, its determination is time-consuming which precludes its assessment at an industrial scale. In this study we sought quantitative relationships between Ki and the pre-germination degree of barley grain lots, assessed through quality tests routinely performed by malthouses [Falling Number (FN), α-Amylase Activity and Carlsberg]. Field pre-germinated lots from one old barley cultivar (Quilmes Palomar) and artificially pre-germinated lots from major varieties currently grown in Argentina were used. Associations between Ki and values obtained from all quality tests analysed were found for Q. Palomar. However, FN was the parameter that yielded the best and simplest explanation of Ki variability. A significant positive linear Ki -FN relationship was also obtained for each modern barley cultivar. 相似文献
183.
为了解生物肥对西藏青稞生长的影响,开展了谷特菌不同施用时期(播前、青稞拔节期),不同施用量对青稞产量影响的试验,供试生物肥为谷特菌,供试青稞品种为春青稞藏青320。在青稞收获期采样分析了青稞生物产量和经济产量,同时采集土样分析了土壤蔗糖酶、微生物量N等指标。结果表明:(1)施用谷特菌促进青稞分蘖,增加成穗数,在拔节期施用还能提高青稞灌浆能力,增加青稞穗粒数,提高青稞产量;(2)施用谷特菌对土壤0~10 cm土层蔗糖酶活性影响大,表现为土壤蔗糖酶活性随谷特菌施用量增加而增强,当施用量相同时,拔节期施用谷特菌导致土壤蔗糖酶活性增强,但对土壤微生物量N影响无统一规律。 相似文献
184.
为了解青稞种子胚胎成熟晚期丰富蛋白(LEA)基因Hva1与青稞抗旱性的关系,以抗旱性强的旱地紫青稞和抗旱性弱的大麻青稞为材料,研究了不同浓度PEG胁迫下Hva1基因在两个青稞品种中的表达模式。结果表明,Hva1基因在抗旱性不同的两个青稞品种中的表达均呈单峰模式,且抗旱性强的旱地紫青稞表达峰值和对应的PEG胁迫浓度均高于抗旱性弱的大麻青稞;PEG胁迫浓度大于13.18%时,旱地紫青稞的Hva1基因表达量高于大麻青稞。可见,Hva1基因的表达在青稞的抗旱中起到重要的作用,为此我们成功构建了青稞Hva1基因的过量表达载体,期望为抗逆性基因在青稞中的应用和抗旱新品种的选育奠定基础。 相似文献
185.
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187.
为给啤酒大麦高光效育种及高产栽培提供理论依据,采用便携式光合分析系统测定和分析了不同基因型啤酒大麦冠层光合生理指标的变化。结果表明,从孕穗期到灌浆末期,基因型间光合速率(Pn)差异都达极显著水平(P<0.01),冠层光合速率阶段变化与产量呈现一定的正相关关系。各次测定Pn与蒸腾速率(Tr)无一致性表现。从抽穗开花期开始,基因型间Tr差异达到极显著水平。从挑旗期开始,基因型间气孔导度(Gs)都表现出极显著差异,并且与Pn保持相对的一致性。从孕穗期至灌浆末期,Pn一直较高的基因型,产量也相对较高,表现最突出的是引自欧美的主栽品种MERIT、Z090M066M和SCARLETT,其Pn分别较平均光合速率高9.70%、8.85%和10.14%,产量分别高8.24%、7.30%和6.63%。 相似文献
188.
为阐明昆仑1号及其3个不同时期衍生品种(系)重要农艺性状的演变规律,对重要农艺性状和产量性状进行了研究。结果表明,昆仑1号衍生品种(系)的株高呈增加趋势,子代株高相对于昆仑1号平均株高分别增加8.17%、18.77%和14.74%;子代叶片类型由长而宽逐渐演变为短而窄,旗叶长宽比逐渐增加,叶面积逐渐减少,该类型变化使株型更加紧凑,有助于增加单位面积的植株数,提高光合总产量,促进青稞的增产;穗长、单株有效穗数、穗粒重和小区产量均显著增加;小穗数和穗粒数变化不明显,千粒重小幅度减少。相关性分析表明,穗粒重、千粒重与产量呈显著正相关,单株有效穗数、穗长、株高对产量呈显著负相关,小穗数和穗粒数与产量间的相关性不显著。因此,昆仑1号的穗大、千粒重高等丰产特性在品种演替中得到了很好的传递。建议西藏青稞育种中,应结合农区畜牧业的发展,保持株高、减少穗长、增加有效小穗数、提高结实率,千粒重和穗粒重并重、主攻小穗数和穗粒数是提高青稞产量的有效途径。 相似文献
189.
190.
Strong adhesion between the hull and the caryopsis is essential for barley to be of good malting quality. Poor hull adhesion, a condition known as grain skinning, is undesirable for malting and downstream processes. At present, the processes mediating hull adhesion during grain development are poorly understood. The barley cultivar Chariot was grown in greenhouse conditions and grain development was recorded at defined growth stages to examine the timing of hull adhesion. Initiation of adhesion was first observed when caryopsis fresh weight and volume were approaching their maximum at 19 days after anthesis, during early dough. Hull adhesion was complete by 27 days after anthesis, or soft dough. Sections of developing grains were observed using light and transmission electron microscopy to examine a lipid-rich cementing layer believed to be responsible for adhesion between the hull and the pericarp. Evidence for a lipid-rich cementing material was supported by the observation that neither pectinase nor cellulase effected hull loosening. Grain growth, the presence of globular material originating from the pericarp and an electron dense material in the cementing layer are discussed in relation to hull adhesion. Grain skinning could be caused by poor adherence of cuticular material or inadequate fusion between cuticles. 相似文献