硫对不同蛋白质含量春小麦面团流变学特性的调节效应

为给小麦优质栽培提供理论依据,以3个不同蛋白质含量的春小麦品种为材料,在不同施氮水平条件下研究了施硫对面团流变学特性的调节效应.结果表明,施尿素60 kg/ha(低氮)和128 kg/ha(高氮)条件下,各品种面团韧性随着施硫量的增加总体上呈降低趋势.高氮条件下,施硫对高蛋白品种面团延展性提高不利,且降低吸水率,但可以增加面团形成时间;施纯硫0～50 kg/ha有利于改善低蛋白品种NKH9面团的延展性,对面团形成时间的调节作用呈负效应;施硫对各品种稳定时间的作用趋势与面团形成时间的作用趋势相同.低氮条件下施硫可增加所有供试品种面团形成时间,改善面团延展性.相关分析结果表明,低氮条件下,施硫对小麦品种野猫和东农7742的W值有提高的作用,但不明显;高氮条件下施硫对W值的作用却呈明显的负效应,但两种氮处理条件下施硫对新克旱9的W值作用呈不显著的负效应;施尿素60 kg/ha条件下施硫可提高高蛋白品种的烘焙指数.高氮条件下,施硫可以明显提高高蛋白品种面团形成时间和稳定时间,但对低蛋白品种的作用却相反.     

Correlations of the Breadmaking Performance of Wheat Flour with Rheological Measurements on a Micro-scale

For the characterization of wheat quality, micro-extension tests for dough and gluten and a micro-baking test were developed using comparable dough compositions, the same mixing temperature and cultivar-specific mixing times. By means of these methods, the flours of 26 wheat samples were studied for dough development time, maximum resistance and extensibility of dough and gluten and loaf volume of the baked products. Standard methods (rapid-mix-test, gluten index determination) were used for comparison. The results indicated that the rheological properties of dough and gluten as well as the gluten index are correlated higher with the optimised micro-baking test than with the standard baking test. If flour protein or wet gluten content is included in the correlations, the extension test of gluten, which can be performed easily and reproducibly, allows a reliable prediction of the loaf volume obtained by the micro-baking test.     

Strain Hardening Properties and Extensibility of Flour and Gluten Doughs in Relation to Breadmaking Performance

The mechanical properties of flour–water doughs and hydrated gluten of different wheat cultivars were determined. Measurements were performed at small deformations (dynamic measurements) as well as at large deformations (biaxial extension measurements). Results of dynamic measurements of flour doughs related poorly to breadmaking quality. For hydrated gluten doughs, all having the same water content, it was found that glutens from wheat cultivars with good baking quality had higher values for the storage modulus,G, and lower values for the loss tangent. The relevant type of deformation around an expanding gas bubble is biaxial extension. Wheats with a good baking performance exhibited greater strain hardening and greater extensibility. The differences in strain hardening observed at 20 °C were also present at 55 °C. No clear effects of NaCl or emulsifiers on the biaxial extension properties of flour dough were found. Extensograms as well as Alveograms from the flour doughs showed that, in general, good baking flours exhibited stronger resistance to extension and a greater extensibility, but differences found were not directly related to the results of the baking tests. The results indicate that the baking performance of dough is related to a combination of at least three different rheological characteristics.     

不同品质类型小麦阿拉伯木聚糖流变性质的研究

为了解阿拉伯木聚糖流变性质及其与小麦品质的关系,对不同品质类型的小麦（强筋、弱筋）阿拉伯木聚糖(简称WEAX)的零剪切黏度（η0）及酶促氧化胶凝能力等指标进行了研究。结果表明,不同品质类型小麦间WEAX溶液的黏度特性存在一定差异,零剪切黏度值（η0）变幅为0.20～56.50 Pa·s,大部分集中在0.20～2.43 Pa·s,个别品种（中优206、烟农19）数值偏差较大。在过氧化物酶体系(POX/H2O2)作用下,WEAX凝胶特性（G′、G″值）差异显著,强筋与弱筋小麦中均存在胶凝能力或强或弱的品种,说明WEAX的上述流变特性与小麦筋力（或硬度）无直接关系。     

Aerenchyma Formation in the Seminal Roots of Japanese Wheat Cultivars in Relation to Growth under Waterlogged Conditions

Abstract

Morphological adaptation of roots is critical for plants to survive under waterlogging. In this study, we evaluated the capacity of wheat to form aerenchyma in seminal roots in combination with the growth angle of the roots. We used five Japanese cultivars from the waterlogging-prone Kanto-Kyushu region in Japan, and a non-Japanese cultivar, Bobwhite for comparison. Seedlings in pot culture were waterlogged at a 3-cm depth for 7 days. The first adverse effect of waterlogging on plant growth was a significant reduction of root dry mass. The reduction rate varied with the cultivar, and it was 19.2% in cv. Shiroganekomugi and 40.0% in cv. Norin 61. Root aerenchyma was initially observed on the 2nd day of waterlogging and developed until the 7th day, in all 6 cultivars. Quantitative analysis of the aerenchyma development revealed no significant difference in radial distribution among the cultivars, whereas a slight difference was found in the axial distribution. As a consequence, the heavier root weight of Shiroganekomugi was not related to either the radial or axial developing capacity of aerenchyma but might be due to the effect of its shallow root angle in the soil. These results suggest that the capacity to form aerenchyma in the seminal root is not sufficient for expression of waterlogging tolerance in the Japanese wheat cultivars.     

潮土区超高产麦田供钾特点与小麦钾素营养研究

综合作者多年来有关超高产小麦钾素营养与钾肥施用的研究，介绍了黄淮海平原潮土区超高产麦田土壤钾素动态变化、超高产小麦钾素营养特点以及施钾对小麦生长发育、形态生理等的影响，强调了在小麦超高产实践中钾素营养研究和钾肥施用的重要性。     

青海高原春小麦HMW—GS等位基因变异及其对面团流变学特性的作用

为了给青海高原春小麦改良提供资料。分析了青海育成和国内外引进的125个春小麦品种(系)的HMW—GS等位基因变异。并测定了其中58个品种(系)在青海高原环境下的面团流变学特性。结果表明：(1)参试春小麦品种(系)的HMW—GS存在广泛的变异。Glu—A1位点出现3个等住基因，Glu—B1住点出现5个等住基因，Glu—D1位点出现4个等位基因；共出现了22种HMW—GS组合形式。其中1.7 8.2 12和N，7 8，2 12组合类型出现频率最高。并发现了个别罕见的变异类型，如2 10，10。(2)亚基组合类型对沉淀值、形成时间、稳定时间、评价值等品质性状影响较大，对籽粒蛋白质含量、出粉率和面粉吸水率的影响不显著。试验还表明，HMW—GS组成与面粉的筋力有密切关系。     

Sulphur Assimilation and Effects on Yield and Quality of Wheat

Deficiency of sulphur (S) has been recognised as a limiting factor for crop production in many regions in the world. In particular, incidence of S deficiency has increasingly been reported in Brassica and cereal crops in Western Europe over the last decade, mainly as a consequence of a massive decrease of atmospheric S inputs. The S requirement of wheat is about 15–20 kg/ha for optimum growth. Reproductive growth of wheat appears to be more sensitive to S deficiency than vegetative growth, with decreased grain size under S-limiting conditions. In addition to the effects on yields, the S status of wheat grain is an important parameter for the quality of wheat products. Limiting S availability has been shown to favour the synthesis and accumulation of S-poor or low-S storage proteins such as ω-gliadin and high molecular weight (HMW) subunits of glutenin at the expense of S-rich proteins. Sulphur deficiency also decreases the proportion of polymeric proteins in total proteins, but shifts the distribution of polymeric proteins toward lower molecular weight. These changes in protein composition are associated with alterations of dough rheology. Significant responses of breadmaking quality to the addition of S fertilisers have been established under field conditions. Recent studies have also shown that breadmaking quality correlated more closely with grain S concentration than with N concentration. Recent progress in cloning genes encoding components involved in sulphate uptake and assimilation has substantially increased our understanding of plant S nutrition and its regulation, and opened up opportunities for manipulation of S uptake and metabolism in plants.     

硫营养对绿茶产量和品质的影响

研究了硫营养对绿茶产量和品质的影响及其可能的机理。试验设2个硫处理(0,50 kg S.ha-1.a-1),每个处理重复4次,完全随机区组设计。结果表明:施硫能够提高产量、增加氨基酸和抗坏血酸(AsA和DAsA)含量,降低茶多酚和酚氨比(TP/AA)。施硫对茶叶品质的改善与降低多酚氧化酶(PPO)的活性、提高硝酸还原酶(NR)和苯丙氨酸解氨酶(PAL)活性有关。     

面粉理化品质性状与兰州拉面品质关系的研究

为了给拉面型小麦品种的科学选育及面粉加工企业的配麦提供科学依据和理论指导，建立快速、简捷的拉面粉评价方法．以甘肃省河西地区近几年推广、试种及新培育的小麦品种(品系)为材料，测定了各个材料的面粉理化性状，分析了面粉主要品质性状与拉面品质之间的关系。研究结果表明，拉面粉的主要理化品质性状对拉面品质的影响在各个方向及作用的大小不同；面筋指数、干面筋含量、蛋白质含量及沉淀值等理化性状与兰州拉面的感官总评分极显著正相关．可作为拉面粉选育、品质评价的理化指标，但蛋白质和沉淀值是影响拉面品质的主要理化品质性状；优质兰州拉面要求较高的面筋指数、干面筋含量、湿面筋含量、蛋白质含量和沉淀值，较低的灰分含量和较高的白度值。     

小麦和土壤中噻虫嗪残留及消解动态分析

为对噻虫嗪在小麦生产上应用的安全性进行评价,通过对小麦籽粒、植株和土壤进行前处理及在样品中添加噻虫嗪,建立其残留量定量检测分析方法;通过两年三地的残留试验,分析了小麦籽粒、植株和土壤中噻虫嗪的残留及消解动态,并对小麦籽粒中的残留量进行风险评估。结果表明,噻虫嗪在小麦籽粒、植株及土壤空白添加平均回收率为79.62%~94.70%,相对标准偏差为0.91%~6.56%,其最小检出量为5.0×10-8g,小麦籽粒、植株及土壤中的最低检测浓度均为0.01mg·kg-1。该检测方法重现性好,准确度、精密度高,可满足噻虫嗪在小麦及土壤中的残留分析要求。2011和2012年,河南、黑龙江和江苏三地噻虫嗪在小麦植株和土壤中的消解半衰期分别为0.85~2.24d和2.77~4.79d;通过不同施药次数、施药量及间隔采样检测,噻虫嗪在小麦籽粒中的最终残留量均≤0.038mg·kg-1,占日允许摄入量的15.04%左右(普通人群噻虫嗪的国家估算每日摄入量是0.25mg),因此按本试验方式进行施药,通常不会对一般人群健康产生不可接受的风险。     

Single Kernel Wheat Hardness and Fracture Properties in Relation to Density and the Modelling of Fracture in Wheat Endosperm

The fracture properties of small, cylindrical samples of endosperm machined from single kernels of several varieties of wheat were measured using three methods: compression, wedge fracture and indentation. In addition, dynamic compression tests were also performed in impact loading. Density measurements using a variable density liquid gradient were carried out on machined endosperm samples that had previously been tested for fracture properties, enabling direct comparisons between their density and fracture properties. Within each variety, a distribution of density and hardness values was found. Soft wheat varieties (Riband, Apollo) showed a broad distribution of density with medians in the range 1340 to 1395 kg/m³, whilst hard varieties such as Mercia and a durum wheat exhibited much narrower distributions and higher mean densities, Mercia being skewed towards higher densities, with a median at around 1410 kg/m³. A considerable amount of overlap in density between the soft and hard variety occurred, with both containing a significant proportion of harder and higher density wheat grains, and the major difference appearing to be the presence in the soft wheat of a large proportion of lower density endosperm in the range 1280 to 1360 kg/m³. The differences in density between endosperm samples were attributed to variations in endosperm porosity, which were correlated with the fracture properties of the endosperm. It is proposed that increased levels of porosity weaken the endosperm structure and are responsible in part for soft endosperm texture. The relationship between endosperm density and fracture properties was non-linear, the failure stress and fracture toughness increasing rapidly as the density approached a limiting value corresponding to the density expected for pore-free endosperm. This indicates that endosperm is a notch sensitive material, where the pores concentrate applied stresses and can act as sites of crack initiation. It was shown that the notch sensitivity of endosperm is qualitatively consistent with models of brittle fracture based on fracture mechanics theory, i.e. stress concentration by voids.     

有机与常规栽培条件下不同春小麦品种产量与品质的差异

为了解有机和常规栽培条件下不同春小麦品种产量与品质形成的差异,进而筛选适宜有机栽培的优质高产春小麦品种,以北方春麦区主栽的10个品种为供试材料,通过大田试验,采用主成分分析与聚类分析相结合的品质-产量综合评价方法,系统分析了有机与常规栽培模式下不同小麦品种籽粒品质和产量的综合表现。结果表明,不同品种间,籽粒产量、籽粒蛋白质品质指标、容重、出粉率和面团流变学特性指标的差异均达显著水平(P<0.05)。与常规栽培相比,有机栽培下10个品种的穗数、穗粒数、千粒重和产量依次降低了15.1%、42.9%、12.5%和21.4%;蛋白质含量、湿面筋含量、沉降值、容重和出粉率分别降低了32.9%、44.0%、52.9%、8.2%和1.0%;吸水率、面团稳定时间、面团形成时间、拉伸面积、面团延展性和最大抗延阻力分别降低了11.5%、36.2%、40.3%、1.0%、20.5%和10.2%。通过主成分分析,从11个品质指标中提取出4个主成分,累计贡献率达到了91.17%,其中贡献较大的指标有蛋白质含量、湿面筋含量、沉降值、拉伸面积、出粉率、最大抗延阻力。根据品质主成分综合得分和产量聚类,在两种栽培...     

Photoinhibitive and Recovery Properties of Hybrid RiceⅡ You 129 under Field Conditions

Photoinhibitive properties of super-high-yielding hybrid riceⅡ you 129 and its adaptation mechanism to strong light stress were investigated by measuring the light-response curve, diurnal variations of net photosynthetic rate and chlorophyll fluorescence parameters of Ⅱ you 129 leaves and compared with Shanyou 63. Photoinhibition of rice flag leaves under field conditions mainly resulted from the increase of thermal dissipation, especially for thermal dissipation depended on the xanthophyll circle, but no destruction of photosynthetic apparatus occurred. Potentially super-high-yielding hybrid rice Ⅱ you 129 was more tolerant to photoinhibition than Shanyou 63, because it had higher light saturation intensity and maximum net photosynthetic rate; more active xanthophyll cycle, and more rapid recovery ability after photoinhibition.     

Increased Cell-Wall Mass and Resistance to Freezing and Snow Mold during Cold Acclimation of Winter Wheat under Field Conditions

Abstract

Accumulation of soluble carbohydrates plays an important role in enhancement of resistance to freezing and snow mold of plants during cold acclimation. Nevertheless, few studies have examined whether changes in cell wall properties are involved in enhancement of resistance during cold acclimation. In this study, four winter wheat cultivars were sown in a field on six different dates during August–October, and their resistance to freezing and snow mold were compared in relation to soluble carbohydrate content and cell-wall mass in leaves. Resistance to freezing and snow mold was much higher in the plants sown on 23 September than in those sown on 9 September. The percentage of cell-wall mass in leaf to total dry mass (%CW) and water-soluble carbohydrate content also increased considerably during 9–23 September. Multiple regression analyses revealed that %CW contributed significantly to freezing resistance, whereas total water-soluble carbohydrate content contributed significantly to snow mold resistance. These results suggest that increased %CW enhances freezing resistance during cold acclimation.     

小麦麸皮营养与质量安全品质分析

为促进我国小麦麸皮资源的加工转化,收集了我国9个小麦主产省12家大型面粉加工企业的商品小麦麸皮样品,对蛋白质、淀粉、膳食纤维、戊聚糖、脂肪、灰分等主要营养成分以及重金属、农药残留、真菌毒素等安全危害因素进行了分析与比较。结果表明,不同来源的小麦麸皮在营养组成上存在一定差异,其中以总淀粉含量差异最大(CV:35.31%),粗蛋白含量差异最小(CV:5.16%);麸皮蛋白的氨基酸组成中,以蛋氨酸含量差异最为显著(CV:20.06%)。质量安全指标中,重金属含量均未超标,农药残留未检出;真菌毒素,仅河北邯郸一家麸皮样品中的脱氧雪腐镰刀菌烯醇(DON)含量超出限量范围。对比所选取12个样品的品质表现,收集于河北邢台、山东滨州和北京的样品,戊聚糖、蛋白质含量较高,总淀粉含量较低,卫生状况良好,可用于小麦麸皮的深加工与综合利用。     

变量施肥条件下冬小麦植株氮与生物量的时空变异

为给作物的田间管理决策提供参考依据,本文以国家精准农业研究示范基地2013-2014年的冬小麦试验为基础,设置常规推荐施氮（NM,施氮量150 kg·hm^-2）、不施氮（CK）、饱和施氮（BH,施氮量为NM处理的150%）、基于SPAD的变量施氮（S）、基于Dualex的变量施氮（D）、基于Multiplex的变量施氮（M）、基于光谱参数OSAVI的变量施氮（A）等8个处理,采用常规统计与地统计分析法探索植株氮素累积量与生物量的时空变化特征,并分析变量施肥对植株氮素累积的影响。结果表明,冬小麦生育期内植株氮素累积量与生物量整体呈上升趋势,在起身期二者变异系数分别为31.32%和28.64%,收获期分别为16.38%和 15.20%;在开花与灌浆期,8个处理间植株氮素累积量差异没有达到极显著水平（P>0.01）;在拔节期与挑旗期,不同处理间生物量差异也均没有达到极显著水平（P>0.01）;在其他时期,CK、BH、NM、A、D处理间二指标的差异均极显著（P<0.01）。地统计分析表明,试验区小麦在开花期植株氮素累积量普遍较低,其块基比为 40.53%,变程为80 m,具有强烈的空间自相关性;灌浆期与收获期空间植株氮素累积量分布较连续,块基比分别为45.84%和43.60%,变程分别为62.9 和67.0 m,西部累积量高于东部;起身期、拔节期、挑旗期植株氮素累积量空间分布差异大,块基比分别为55.14%、57.59%和72.74%,变程分别为28.9、41.3和31.9 m,南部含量高于北部;生物量在起身期、开花期、收获期空间分布图连续性强,挑旗期块基比为69.22%,变程最小,为10.4 m,空间分布差异大,拔节期与灌浆期块基比分别为64.59%和72.04%,变程分别为34.5 和27.3 m,有中等程度的空间自相关性;试验区在起身期南部生物量大于北部,开花期、灌浆期与收获期西部生物量高于东部。     

Effect of Barley and Barley Components on Rheological Properties of Wheat Dough

The effects of addition of whole barley and barley components (starch, β-glucans and arabinoxylans) on rheological properties of dough prepared from wheat flours with variable gluten quality (cv. Glenlea, extra-strong; cv. Katepwa, very strong; cv. AC Karma, strong; and cv. AC Reed, weak) were investigated in these studies using Mixograph and dynamic rheological measurements. Whole barley meal, starch and non-starch polysaccharides from hulless barley with variable starch characteristics (normal, high amylose, waxy, and zero amylose waxy) were tested. Upon addition of either β-glucans or arabinoxylans, significant increases in peak dough resistance, mixing stability, and work input were recorded in all flours. The addition of starch to various wheat flours reduced the strength of the respective flour-water doughs. The improvement of dough strength upon addition of waxy or zero amylose waxy barley meal was associated with the high content of total and soluble β-glucans present in barley samples. The addition of arabinoxylans or β-glucans increased the G′ of wheat doughs; arabinoxylans had a greater effect than β-glucans. Starch substantially decreased the elastic modulus of dough prepared from cv. Glenlea but waxy and high amylose starches increased the G′ of dough prepared from cv. AC Karma. A combination of the high amounts of non-starch polysaccharides and unusual starch characteristics in barley seems to balance the negative effects associated with gluten dilution brought about by addition of barley into wheat flour.     

2006-2014年我国小麦品质在年度和品质区之间的变化

为了解我国小麦在年度间和品质区之间的品质变化,对2006-2014年我国10个品质区637个小麦品种6 339份样品的籽粒品质、面粉品质和面团流变学特性进行测定与分析.结果表明,(1)我国小麦籽粒蛋白质含量较高,平均达13.94％,湿面筋平均含量为30.4％;但蛋白质质量一般,沉淀指数平均值为32.1mL,稳定时间平均值为5.8 min,相对美国硬红冬小麦较低.(2)年度间小麦品质呈规律性偏态分布,平均值在年度间变化无规律;从品质类型看,强筋、弱筋小麦比例在减少,中筋小麦比例在增加.(3)品质区之间小麦质量差异较大,东北、北部和西北春麦区、华北北部强筋麦区、黄淮北部强筋与中筋麦区、黄淮南部中筋麦区蛋白质数量性状高于长江中下游中筋与弱筋麦区、四川盆地中筋与弱筋麦区和云贵高原麦区;蛋白质质量性状表现较为复杂,其中长江中下游中筋与弱筋麦区小麦稳定时间一般,但最大拉伸阻力较高,华北北部强筋麦区、黄淮北部强筋与中筋麦区和黄淮南部中筋麦区小麦稳定时间较高,但最大拉伸阻力一般;各品质区以中筋小麦为主.我国小麦总体质量表现为中等水平.小麦品种类型结构的变化是导致年度间小麦质量以及品质区小麦质量变化的重要原因,北方强筋麦区优质强筋小麦品种和南方弱筋麦区优质弱筋小麦品种减少,反映了强调产量、大力推广高产品种的生产实际情况.     

茶叶粉对小麦面粉流变学及糊化特性的影响

为进一步提高茶叶在食品工业中的应用范围,以小麦西农538(中筋)为供试材料,分别添加0、2%、4%、6%、8%和10%的绿茶、红茶和黑茶3类茶叶粉于面粉中,并对其进行面团流变学特性及糊化特性分析。结果表明,3类茶叶粉均可显著改善面团的流变学特性及糊化特性。随着茶叶粉添加量的增加,面团吸水率均显著增大;添加2%~10%的绿茶粉及6%~10%的黑茶粉,面团的形成时间和稳定时间均显著提高,弱化度均显著降低。添加6%的绿茶粉时,面团的拉伸能量和最大拉伸阻力增幅均达到最大值,延伸度出现小幅度升高的拐点;添加4%的红茶粉,面团的拉伸面积显著增大,继续增加添加量则变化不明显;黑茶和红茶粉添加量分别大于4%和6%时,面团延伸度均显著降低。面粉中添加适量的茶叶粉可改善面粉的品质,绿茶粉的添加对面团网络结构形成速度和面团筋力的改良效果大于红茶粉和黑茶粉。面粉糊化的峰值黏度、低谷黏度、最终黏度、峰值时间、回生值随着茶叶粉添加量的增大均呈不同幅度的降低趋势;3类茶叶粉对面粉糊化的热稳定性具有不同程度的改善作用。