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1.
Pakistani wheat varieties are grown over a wide agro-climatic range and as such are anticipated to exhibit yield and quality differences. It is therefore necessary to investigate the nutritional status of wheat varieties in terms of biochemical and physiochemical characteristics available for food and nutritional purposes in Pakistan. The result shows that wheat grains of different varieties contain a net protein level of 9.15%~10.27%, 2.15%~2.55% total fats, 1.72%~1.85% dietary fibers,77.65×10^-6~84.25×10^-6 of potassium and 7.70× 10 6~35.90× 10^-6 of sodium ions concentration, 0.24× 10^-6~0.84× 10^-6 of phosphorus, 1.44%~2.10% ash, 31.108~43.602 g of thousand grain mass (TGM) and 8.38%~9.67% moisture contents. This study is significant in providing an opportunity to explore the available wheat varieties and to further improve their nutritional excellence and also essential for setting nutritional regulations for domestic and export purposes.  相似文献   

2.
试验结果表明,博爱7422小麦种子以5%、10%、20%、30%、50%和80%六种比例分别与周麦10号种子混播,其后代籽粒产量与两个品种单作相比,有一定的增产作用。其中以博爱7422小麦种子占30%和50%两个处理增产作用最大.  相似文献   

3.
Pakistani wheat varieties are grown over a wide agro-climatic range and as such are anticipated to exhibit yield and quality differences. It is therefore necessary to investigate the nutritional status of wheat varieties in terms of biochemical and physiochemical characteristics available for food and nutritional purposes in Pakistan. The result shows that wheat grains of different varieties contain a net protein level of 9.15%~10.27%, 2.15%~2.55% total fats, 1.72%~1.85% dietary fibers, 77.65×10-6~84.25×10-6 of potassium and 7.70×10-6~35.90×10-6 of sodium ions concentration, 0.24×10-6~0.84×10-6 of phosphorus, 1.44%~2.10% ash, 31.108~43.602 g of thousand grain mass (TGM) and 8.38%~9.67% moisture contents. This study is significant in providing an opportunity to explore the available wheat varieties and to further improve their nutritional excellence and also essential for setting nutritional regulations for domestic and export purposes.  相似文献   

4.
为考察教学时段因素对班级总体课程学习效果影响的显著性,作者对班级总体课程学习情况进行了一次实际观察,获得了近似于单因素实验条件下的两个班级总体课程成绩的样本,并对两个样本进行了比较分析,由此推断出教学时段因素对总体课程学习效果的影响.文章在分析过程中使用了MATLAB软件中的统计分析工具包.  相似文献   

5.
利用20个品种(系)探讨了小麦部分生理性状的遗传变异及其与产量的关系.结果表明,除生殖生长期外,其余性状在小麦基因型间均存在显著的遗传差异.生物学产量、叶绿素含量、营养生长期、生殖生长期与营养生长期之比与产量相关显著,且遗传力较高,可作为产量选择的间接指标.高产品种在经济系数、生物学产量、叶绿素含量、叶面积等性状上存在优势,在干物质积累上具有灌浆速度快的特点.  相似文献   

6.
7.
高稳系数法在小麦新品种高产稳定性分析中的应用   总被引:2,自引:0,他引:2  
应用高稳系数法分析了1999—2000年度国家黄淮南片小麦品种区试冬水组10个参试品种(系)的高产稳产性,并与常用的统计分析方法进行比较和分析,结果表明,高稳系数法是分析小麦新品种(系)高产稳产性准确而简便的方法.  相似文献   

8.
The effects of CO2 enrichment on the growth and glucosinolate (GS) concentrations in the bolting stem of Chinese kale (Brassioa alboglabra L.) treated with three nitrogen (N) concentrations (5, 10, and 20 mmol/L) were investigated. Height,stem thickness, and dry weights of the total aerial parts, bolting stems, and roots, as well as the root to shoot ratio, significantly increased as CO2 concentration was elevated from 350 to 800 μl/L at each N concentration. In the edible part of the bolting stem,11 individual GSs were identified, including 7 aliphatic and 4 indolyl GSs. GS concentration was affected by the elevated CO2 concentration, N concentration, and CO2×N interaction. At 5 and 10 mmol N/L, the concentrations of aliphatic GSs and total GSs significantly increased, whereas those of indolyl GSs were not affected, by elevated atmospheric CO2. However, at 20 mmol N/L,elevated CO2 had no significant effects on the concentrations of total GSs and total indolyl GSs, but the concentrations of total aliphatic GSs significantly increased. Moreover, the bolting stem carbon (C) content increased, whereas the N and sulfur (S) contents decreased under elevated CO2 concentration in the three N treatments, resulting in changes in the C/N and N/S ratios.Also the C/N ratio is not a reliable predictor of change of GS concentration, while the changes in N and S contents and the N/S ratio at the elevated CO2 concentration may influence the GS concentration in Chinese kale bolting stems. The results demonstrate that high nitrogen supply is beneficial for the growth of Chinese kale, but not for the GS concentration in bolting stems, under elevated CO2 condition.  相似文献   

9.
The effects of CO2 enrichment on the growth and glucosinolate (GS) concentrations in the bolting stem of Chinese kale (Brassica alboglabra L.) treated with three nitrogen (N) concentrations (5, 10, and 20 mmol/L) were investigated. Height, stem thickness, and dry weights of the total aerial parts, bolting stems, and roots, as well as the root to shoot ratio, significantly increased as CO2 concentration was elevated from 350 to 800 μl/L at each N concentration. In the edible part of the bolting stem, 11 individual GSs were identified, including 7 aliphatic and 4 indolyl GSs. GS concentration was affected by the elevated CO2 concentration, N concentration, and CO2×N interaction. At 5 and 10 mmol N/L, the concentrations of aliphatic GSs and total GSs significantly increased, whereas those of indolyl GSs were not affected, by elevated atmospheric CO2. However, at 20 mmol N/L, elevated CO2 had no significant effects on the concentrations of total GSs and total indolyl GSs, but the concentrations of total aliphatic GSs significantly increased. Moreover, the bolting stem carbon (C) content increased, whereas the N and sulfur (S) contents decreased under elevated CO2 concentration in the three N treatments, resulting in changes in the C/N and N/S ratios. Also the C/N ratio is not a reliable predictor of change of GS concentration, while the changes in N and S contents and the N/S ratio at the elevated CO2 concentration may influence the GS concentration in Chinese kale bolting stems. The results demonstrate that high nitrogen supply is beneficial for the growth of Chinese kale, but not for the GS concentration in bolting stems, under elevated CO2 condition. Project (No. 2007CB109305) supported by the National Basic Research Program (973) of China  相似文献   

10.
Freshwater shortage is the main problem in Heilonggang lower-lying plain, while a considerable amount of underground saline water is available. We wanted to find an effective way to use the brackish water in winter wheat production. Surface mulch has significant effect in reducing evaporation and decreasing soil salinity level. This research was aimed at comparing the effect of different mulch materials on winter wheat production. The experiment was conducted during 2002-2003 and 2003-2004. Four treatments were setup: (1) no mulch, (2) mulch with plastic film, (3) mulch with corn straw, (4) mulch with concrete slab between the rows. The result indicated that concrete mulch and straw mulch was effective in conserving soil water compared to plastic film mulch which increased soil temperature. Concrete mulch decreases surface soil salinity better in comparison to other mulches used. Straw mulch conserved more soil water but decreased wheat grain yield probably due to low temperature. Concrete mulch had similar effect with plastic film mulch on promoting winter wheat development and growth.  相似文献   

11.
Objective: This study was to assess the influence of interaction of combination of immobilized nitrogen cycling bacteria (INCB) with aquatic macrophytes on nitrogen removal from the eutrophic waterbody, and to get insight into different mechanisms involved in nitrogen removal. Methods: The aquatic macrophytes used include Eichhornia crassipes (summer-autumn floating macrophyte), Elodea nuttallii (winter-growing submerged macrophyte), and nitrogen cycling bacteria including ammonifying, nitrosating, nitrifying and denitrifying bacteria isolated from Taihu Lake. The immobilization carriers materials were made from hydrophilic monomers 2-hydroxyethyl acrylate (HEA) and hydrophobic 2-hydroxyethyl methylacrylate (HEMA). Two experiments were conducted to evaluate the roles of macrophytes combined with INCB on nitrogen removal from eutrophic water during different seasons. Results: Eichhornia crassipes and Elodea nuttallii had different potentials in purification of eutrophic water. Floating macrophyte+bacteria (INCB) performed best in improving water quality (during the first experiment) and decreased total nitrogen (TN) by 70.2%, nitrite and ammonium by 92.2% and 50.9%, respectively, during the experimental period, when water transparency increased from 0.5 m to 1.8 m. When INCB was inoculated into the floating macrophyte system, the populations of nitrosating, nitrifying, and denitrifying bacteria increased by 1 to 2 orders of magnitude compared to the un-inoculated treatments, but ammonifying bacteria showed no obvious difference between different treatments. Lower values of chlorophyll a, CODMn, and pH were found in the microbial-plant integrated system, as compared to the control. Highest reduction in N was noted during the treatment with submerged macrophyte+INCB, being 26.1% for TN, 85.2% for nitrite, and 85.2% for ammonium at the end of 2nd experiment. And in the treatment, the populations of ammonifying, nitrosating, nitrifying, and denitrifying bacteria increased by 1 to 3 orders of magnitude, as compared to the un-inoculated treatments. Similar to the first experiment, higher water transparency and lower values of chlorophyll a, CODMn and pH were observed in the plant+ INCB integrated system, as compared to other treatments. These results indicated that plant-microbe interaction showed beneficial effects on N removal from the eutrophic waterbody.  相似文献   

12.
This study on the effect of land use on soil quality in relation to forms and toxicity of aluminum in red soils (Ultisol) in southeast China showed that in general, the extractable order for soil active aluminum by four extractants was: NaOH 0.5 mol/L > HCl 1 mol/L > NH4Ac 1 mol/L > KCl 1 mol/L . Different uses of the red soils, developed from Quarternary red clay with the similar hydrogeological environment, greatly affected the amount of active aluminum, especially the exchangeable Al3+. The order of exchangeable Al3+ (Al mg/kg) in the red soils with different land uses was: barren land (740) > tea garden (663) > peach garden (432) > citrus garden (234) > paddy soil (127). The content of water soluble aluminum in the red soils was highly sensitive to soil acidity.  相似文献   

13.
Fermentation ofPhaffia rhodozyma is a major method for producing astaxanthin, an important pigment with industrial and pharmaceutical application. To improve astaxanthin productivity, single factor and mixture design experiments were used to investigate the effects of nitrogen source on Phaffia rhodozyma cultivation and astaxanthin production. Results of single factor experiments showed nitrogen source could significantly affect P. rhodozyma cultivation with respect to carbon source utilization, yeast growth and astaxanthin accumulation. Further studies of mixture design experiments using (NH4)2SO4, KNO3 and beef extract as nitrogen sources indicated that the proportion of three nitrogen sources was very important to astaxanthin production. Validation experiments showed that the optimal nitrogen source was composed of 0.28 g/L (NH4)2SO4, 0.49 g/L KNO3 and 1.19 g/L beef extract. The kinetic characteristics of batch cultivation were investigated in a 5-L pH-stat fermentor. The maximum amount of biomass and highest astaxanthin yield in terms of volume and in terms of biomass were 7.71 mg/L and 1.00 mg/g, respectively.  相似文献   

14.
职业学校实施分层次教学是“以人为本,因材施教,实事求是,各有所成”教育思想的切实体现,本就分层次教学的基本内容及分层次教学在实践中应关注的若干问题进行了探究,旨在为职业学校进一步深化分层次教学改革提供参考。  相似文献   

15.
We investigated how different levels of information presented by various technologies affected secondary students' understanding of acid, base, and pH concepts. Secondary students who were selected for the study had just completed their study of acid–base chemistry. No attempt was made to provide further instruction. We analyzed changes in the understanding of individual students by constructing concept maps from the propositions that the students used in interviews conducted before and after a series of acid–base titrations. After the initial interview, students were divided into three groups. Within each group, students individually performed the same set of titrations using different technologies: chemical indicators, pH meters, and microcomputer-based laboratories (MBL). After the titrations were completed, all students were interviewed again. We found that students using MBL exhibited a larger positive shift in their concept map scores, which indicates a greater differentiation and integration of their knowledge of acids and bases. The chemical indicator students exhibited a more moderate positive shift in their concept map scores, and the pH meter students exhibited a smaller positive shift. We also found that the MBL students constructed more inappropriate links in their concept maps than the chemical indicator or pH meter students. However, we speculate that this increased number of inappropriate links indicates a high level of involvement with the technology. We therefore argue that the level of information offered by the technology affected students' understanding of the chemical concepts.  相似文献   

16.
This study investigated the statistical relationships between four motivational variables (i.e., intrinsic and extrinsic goal orientations, self-efficacy and perceived task value) and three types of learning practices (test drilling, rote learning and normal learning activities) based on the self-reported data of 258 undergraduate English majors preparing for a high-stakes English language test in China. Consistent with previous findings conducted in both washback and non-washback contexts, extrinsic goals geared towards the test significantly positively contributed to students’ test drilling and rote learning activities, while intrinsic goals positively affected their normal learning activities overall. Unexpectedly, intrinsic goals were also found to have a statistically positive, though indirect, effect on test drilling; meanwhile, both intrinsic and extrinsic goal orientations exerted positive influence, through the mediation of perceived task value, on rote learning activities. These findings would help us pinpoint how motivational factors interact with test impact in shaping washback on learning, and thus constitute evidence to underpin possible claims about washback from the target test (Messick, 1996). Implications of these findings for how to address negative washback are also discussed at the end of paper.  相似文献   

17.
针对新疆少数民族学生的实际情况加强实践环节的教学,将不同年级不同民族的学生组织在一起共同完成了生理学的设计性实验。在此基础上,探讨了对不同年级和不同民族的学生开设综合性和设计性实验的体会:正确认识综合性和设计性实验;注意实验的可行性;编写翔实的实验教学大纲;合理搭配民、汉语言学生和高、低年级学生;注重对学生协作能力的培养等。这种方式既提高学生对专业知识的理解,也锻炼了他们取长补短、团结协作的能力。  相似文献   

18.
INTRODUCTION Barley (Hordeum vulgare L.) is widely used as food and feed, but its most economically important use is for malting and brewing. Many barley charac- ters are involved in malt quality, of which protein content is the most important, as it has been observed to be related to malt qualities, such as extract and diastatic power (Weston et al., 1993; Eagles et al., 1995).Barley suitable for malting should have low grain protein content, as high protein content will not only reduce…  相似文献   

19.
The purpose of this paper is to empirically explore and theoretically discuss Swedish religious studies (RE) teachers’ understanding of religions as similar and different. In Sweden, RE is a mandatory subject and presents all the world’s major religions to students. Teachers of RE therefore need to relate to the various relations between the religions. A qualitative interview study with Swedish RE teachers (n?=?7) in Swedish secondary schools was performed to determine how they conceptualise religion and present ‘religion’ to their students. The teachers (m?=?3; f?=?4) were chosen from schools with a variety of ethnically homogenous and heterogeneous compositions of students. The teachers’ conceptions of ‘religion’ can be described according to two main categories: as something universal or as something dependent on the cultural context. These two main orientations are described more closely in this paper. The teachers’ conceptions are also discussed from the perspective of possible consequences for educating citizens in the Swedish school system. It is suggested that RE teachers’ conceptions of religions as similar and different facilitate and constrain identification and encounters with others as religious subjects.  相似文献   

20.
Effects of cadmium (Cd) on microbial biomass, activity and community diversity were assessed in a representative variable charge soil (Typic Aquult) using an incubation study. Cadmium was added as Cd(NO3)2> to reach a concentration range of 0~16 mg Cd/kg soil. Soil extractable Cd generally increased with Cd loading rate, but decreased with incubation time. Soil mi-crobial biomass was enhanced at low Cd levels (0.5~1 mg/kg), but was inhibited consistently with increasing Cd rate. The ratio of microbial biomass C/N varied with Cd treatment levels, decreasing at low Cd rate (<0.7 mg/kg available Cd), but increasing progressively with Cd loading. Soil respiration was restrained at low Cd loading (<1 mg/kg), and enhanced at higher Cd levels. Soil microbial metabolic quotient (MMQ) was generally greater at high Cd loading (1~16 mg/kg). However, the MMQ is also affected by other factors. Cd contamination reduces species diversity of soil microbial communities and their ability to metabolize different C substrates. Soils with higher levels of Cd contamination showed decreases in indicator phospholipids fatty acids (PLFAs) for Gram-negative bacteria and actinomycetes, while the indicator PLFAs for Gram-positive bacteria and fungi increased with increasing levels of Cd contamination.  相似文献   

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