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71.
2004-2011年中国主产省小麦蛋白质品质分析   总被引:7,自引:2,他引:5  
 【目的】分析2004—2011年来中国主产区小麦蛋白质品质检测数据,探讨小麦蛋白质品质年度和地区间变化规律。【方法】对2004—2011年分别来自冀、鲁、豫、苏、皖5个小麦主产省的4 235份小麦样品的籽粒蛋白质含量、湿面筋含量、沉淀值、稳定时间和最大拉伸阻力进行分析。【结果】2004—2011年,中国主产省小麦籽粒蛋白质含量和湿面筋含量平均值变化不大,沉淀值呈明显下降趋势,表明近年来小麦内在品质变差;不同主产省之间小麦蛋白质含量差异较大,呈明显北高南低和东高西低趋势。【结论】近年来片面追求高产已影响了中国小麦的整体品质,致使强筋麦产区小麦面筋强度降低、弱筋麦产区小麦面筋增加。应根据各地区的不同条件发展适合本地区的高产优质小麦品种。  相似文献   
72.
不同灌溉处理对强筋小麦加工品质的影响   总被引:1,自引:0,他引:1  
赵广才  常旭虹  杨玉双  丰明 《核农学报》2010,24(6):1232-1237
在小麦生育期降水47.9mm的条件下,以7个强筋小麦品种为供试材料,采用二因素裂区设计试验,分析春季灌水1~4次4种处理(每次灌水600m3·hm-2)对小麦加工品质的影响。结果表明,各品种小麦的面筋含量和面筋指数随灌水次数增加而升高,其中春季灌3水(春2叶露尖、春5叶露尖和开花期灌水)和灌4水(春2叶露尖、春5叶露尖、开花期和灌浆期灌水)的湿面筋含量显著高于春季灌1水(春5叶露尖灌水)和2水(春5叶露尖和开花期灌水)的处理;灌2、3、4水的面团形成时间和吸水率均比灌1水处理显著增加;灌2水的面团稳定时间比灌1水的显著延长;灌3水和4水的面包体积显著大于灌1水和2水处理。供试品种中以皖麦38和临优145面筋含量较高,8901-11面筋指数最高,面团形成时间和稳定时间最长,且与其他品种差异显著;豫麦34面包体积最大,面包评分最高,与其他品种差异显著。不同品种及不同品质指标对灌水的反应程度不同,其中烟农19和济麦20的面筋含量对灌水反应较小,烟农19的面包体积对灌水处理反应不敏感,其他品种的面包体积对灌水处理反应较大。因此认为,在干旱年份春季灌水3次,对改善小麦加工品质有利,但不同品种的加工品质对灌水反应有别。  相似文献   
73.
74.
Wheat yield and quality are dependent largely on nitrogen (N) availability. In this study, we performed the first metabolomic analysis of the response to high-N fertilizer during wheat grain development using non-targeted gas chromatography-mass spectrometry (GC–MS). Quality parameter analyses demonstrated that high-N fertilizer application led to a significant increase in grain protein content and improvement in starch and bread-making quality. Comparative metabolomic profiling of six grain developmental stages resulted in identification of 74 metabolites, including amino acids, carbohydrates, organic acids and lipids/alcohol, which are primarily involved in carbon and N metabolism. Under high-N fertilizer treatment, numerous metabolites accumulated significantly during grain development. Principal component analysis revealed two principal components as being responsible for the variances resulting from N-fertilizer treatments. Metabolite–metabolite correlation analysis demonstrated that the high-N treatment group had a greater number of positive correlations among metabolites, suggesting that high-N fertilizer treatment induced a concerted metabolic change that resulted in improved grain development. Particularly, the high-N treatment-mediated significant accumulation of metabolites involved in the TCA cycle, starch and storage protein synthesis could be responsible for the improvement of grain yield and quality. Our results provide new insight into the molecular mechanisms of wheat grain development and yield and quality.  相似文献   
75.
Z. Bedõ  G. Vida  L. Láng  I. Karsai 《Euphytica》1998,100(1-3):179-182
Due to their broad population diversity, old wheat varieties or landraces play an important role in increasing the genetic variability of agronomic traits. On these grounds, an analysis was made of the high molecular weight (HMW) glutenin subunit composition of the old Hungarian wheat variety Bánkúti 1201. It was found that several genotypes with differing breadmaking qualities can be distinguished for this character. When using old varieties in breeding, it is possible to broaden the genetic background of characters responsible for breadmaking quality by separating the populations. A more detailed analysis of the protein composition of germplasm created in this way will be required to obtain a better understanding of this complex character for its conscious introduction into breeding programmes. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
76.
覆膜对不同小麦品种的品质影响   总被引:1,自引:0,他引:1  
不同小麦品种覆膜后,籽粒容重有不同程度的提高;蛋白质含量比同期晚播提高 1.8%,与正常播种差异不显著。与正常露地播种比,覆膜对不同品种的于、湿面筋和沉淀值没有影响,但品种间的容重、于面筋、湿面筋和沉淀值存在较大的差异。  相似文献   
77.
The rheological properties of short doughs of various composition were determined in dynamic shear experiments at small deformation. Regardless of composition, the linear region was very limited; beyond it significant structure breakdown occurred. Furthermore, an increase in storage modulus was invariably observed in time-sweep experiments. In addition to oscillatory experiments, conductimetry was used to evaluate short doughs with different fat types and fat content. Short doughs showed differences in mechanical spectra and in conductivity, depending on fat content and fat type. These results are considered in terms of the structure of short doughs. It is concluded that short doughs are bicontinuous systems; reducing the fat content or changing its rheological properties relative to those of the non-fat phase results in fat-dispersed systems. At small deformation, the rheological properties of the non-fat phase are largely determined by flour/starch particles.  相似文献   
78.
The effect of dietary substitution of animal and/or plant protein sources for fishmeal on the growth and body composition of juvenile abalone was determined. Nine experimental diets in triplicate were prepared: Con, SM, PM, CM, SPM, MB, SM+CM, SM+SPM and CM+SPM diets. A 350 g kg?1 fishmeal was included in the Con diet, and the whole fishmeal was substituted with a 580 g kg?1 soybean meal (SM), 335 g kg?1 poultry meal (PM), 370 g kg?1 corn gluten meal (CM), 325 g kg?1 silkworm pupae meal dehydrated (SPM), 590 g kg?1 meat and bone meal (MB), the combined 290 g kg?1 soybean meal and 180 g kg?1 corn gluten meal (SM+CM), 290 g kg?1 soybean meal and 160 g kg?1 silkworm pupae meal dehydrated (SM+SPM) and 180 g kg?1 corn gluten meal and 170 g kg?1 silkworm pupae meal dehydrated (CM+SPM) diets respectively. All experimental diets were iso‐nitronic and iso‐lipidic. The survival of abalone fed with the SM and SM+SPM diets was higher than that of abalone fed with the CM, SPM, MB and CM+SPM diets. Weight gain of abalone fed with the SM+SPM diet was higher than that of abalone fed with all the other experimental diets, except for that of abalone fed with the SM+CM diet. The combined soybean meal and corn gluten meal (SM+CM) or silkworm pupae meal (SM+SPM) could be replaced with the whole fishmeal in the diet for abalone and improved its performance.  相似文献   
79.
Corn gluten meal (CGM), pea protein isolate (PPI) and their mixture (CPP, 1:1 ratio) were evaluated as fishmeal (FM) alternatives in black sea bream (Acanthopagrus schlegelii) juveniles (9.02 ± 0.12 g). A FM diet was designed as control, and other six diets had 20% and 40% FM protein replaced by CGM, PPI and CPP, respectively, with the supplementation of crystalline methionine, arginine and lysine. After the 8‐week feeding trial, significantly lower weight gain was found in fish fed the 40% CGM diet (p < .05), whereas other treatments had no statistical difference (p > .05). The values of feed efficiency ratio and feed intake, as well as proximate compositions of muscle and whole body, were not significantly influenced in all treatments. Apparent digestibility coefficients (ADCs) of dry matter, crude protein, threonine, valine, methionine, isoleucine, leucine, phenylalanine and lysine were significantly influenced by protein source. Fish fed the 40% CGM diet had significantly higher content of essential amino acid in muscle than that of the 20% PPI diet. Fish fed the 40% CGM diet had significantly lower content of serum cholesterol than other treatments (p < .05). Elevated serum superoxide dismutase activity was found in fish fed the 40% plant protein diets. In conclusion, between 20% and 40% FM protein could be replaced by CGM, while about 40% FM protein derived from PPI and CPP could be applied in black sea bream.  相似文献   
80.
为明确不同施氮措施对优质小麦产量及品质的影响,以强筋品种郑麦366和中强筋品种郑麦7698为材料,设置不施氮(N0)、基施纯氮210kg/hm2(N210+0)、基施纯氮150kg/hm2+追施纯氮60kg/hm2(N150+60)和基施纯氮150kg/hm2+追施纯氮120kg/hm2(N150+120)4个施氮处理,连续3年分析不同施氮措施下的产量、籽粒与麦粉品质。结果表明,不同施氮措施对小麦产量和品质的影响年际间变化较大;丰产年份(2018-2019年度)N150+60处理的籽粒和蛋白质产量均高于其他处理;N150+120处理2017-2018年度2个品种、2019-2020年度郑麦7698的小麦粉湿面筋含量显著高于N150+60和N0处理;不同施氮措施下2个品种的小麦粉面团稳定时间以N150+60或N150+120处理较长;N150+60处理与其他处理相比显著增加了2019-2020年度的郑麦366面团最大拉伸阻力;与N210+0和N0处理相比,N150+60和N150+120处理显著增加了2018-2019和2019-2020年度的郑麦7698面团最大拉伸阻力。综上分析,小麦...  相似文献   
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