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1.
Seedlings of two strawberry cultivars ‘Camarosa’ and ‘Chandler’ were grown using perlite in a greenhouse for 20 days, and then plants were watered with nutrient solution containing 0, 8.5, 17.0, and 34.0 mM sodium chloride (NaCl) for 6 months. Sodium chloride treatments generally reduced the leaf and root dry weight. Relative water content (RWC) of leaves was maintained despite the increased salt concentrations while loss of turgidity was increased by sodium chloride (NaCl) treatments in both cultivars. As the most variable amino acids, aspartic acid, glutamic acid, arginine, proline, serine, and alanine were determined under salt stress in plants. Sodium chloride treatments generally increased sodium (Na) and chloride (Cl) contents in all plant parts. The plants were able to maintain high potassium (K) levels in the aerial parts with the 8.5 mM NaCl treatment. It can be concluded that ‘Camarosa’ has the ability to osmotic regulation. ‘Chandler’ also tolerates the salt injury at low salt concentrations.  相似文献   

2.
ABSTRACT

Integrated management of soil organic matter and nutritional status of crop plants is essential to sustain the production of organic farming systems. Thus, a 2–year field experiment was conducted to examine the effects of soil additions (192 kg N ha–1, humic+192 kg N ha–1, humic+144 kg N ha–1 and humic+96 kg N ha–1) and foliar applications (amino acids, Azotobacter+yeast, and amino acids plus Azotobacter+yeast) as various fertilizer resources on growth and yield of wheat. Results showed that humic+192 kg N ha–1 × amino acids plus Azotobacter+yeast were the effective combination for producing the highest values of flag leaf area, total dry weight, tiller number m–2, spike weight m–2, and grain yield ha–1. Under foliar application of amino acids plus Azotobacter+yeast, reducing N supply from recommended rate (192 kg N ha–1) to 144 kg N ha–1+ humic achieved higher values of all yield traits, with a saving of 25% of applied mineral nitrogen as well as enhancing nitrogen use efficiency.  相似文献   

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To devise effective procedures for the remediation of soil contaminated by VOCs, an improved understanding of their fate and transport mechanisms in soil is essential. To show the effect of plants on the dissipation of 1,1,1-trichloroethane (TCA), trichloroethylene (TCE) and tetrachloroethylene (PCE), two types of experiments, vial and column, were conducted. The results suggested that keeping the soil moisture content at field capacity is desirable for VOCs dissipation. All VOCs were dissipated quickly in unplanted columns than planted conditions in early periods of the experiment because more volatilization occurred in unplanted conditions. The plants could take up and retard volatile contaminants, and prevent contamination of ambient air. Although the time for acclimation for microbial communities to contaminants for enhanced biodegradation should be considered, phytoremediation is potentially a cost-effective remediation technique for soils contaminated by volatile organic compounds (VOCs).  相似文献   

5.
通过盆栽试验方法,在荧蒽污染的黄棕壤和潮土上种植水稻和小麦,分别设置空白(CK)、低(L)、中(M)、高(H)4个污染浓度水平,比较荧蒽对作物生长的影响和两种不同土壤中植物体荧蒽的分布情况。结果显示,在试验设置的荧蒽污染浓度下,荧蒽未对两种植物的生长造成抑制,相反还促进了植物某些部位的生长;水稻和小麦各部位的荧蒽含量随土壤荧蒽含量的增加而增大;植物体内荧蒽的传导系数随土壤荧蒽含量的增加而减小,且两种土壤的趋势一致。黄棕壤和潮土有机质、养分、阳离子交换量等性质影响植物体内荧蒽的运移和富集;水稻茎叶对荧蒽的富集能力强于小麦,而小麦籽粒富集荧蒽的能力强于水稻。  相似文献   

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7.
Volatile organic compounds in the ambient air were measured at four locations in Rousse, Bulgaria for a one year period. A gas chromatograph/mass spectrometer equipped with a cryogenic concentrator was used to analyse the air samples. Forty one compounds (aromatic hydrocarbons and halogen-derivatives of aliphatic and aromatic hydrocarbons) were analysed by EPA method TO-14. Aromatic hydrocarbons, benzene, toluene, styrene, isomers of xylene and isomers of trimethyl benzene were the most frequently occurring pollutants. Styrene, isomers of xylene and isomers of trimethyl benzene frequently exceeded the concentration limits. Among the halogen derivatives, the concentration of chloroform was always very high. A concept called ‘degree of pollution’ was proposed to clarify the contribution of each pollutant to the total air-pollution. Suggestions were made on the need to introduce an integral tolerance parameter to describe the total impact on air-pollution.  相似文献   

8.
The influence of fermentation temperatures (8, 16, and 32°C) and yeast levels (2, 4, and 6%) on the formation of volatile compounds in the crumb of whole‐meal wheat bread was investigated. Volatile compounds were extracted by dynamic headspace extraction and analyzed by gas chromatography–mass spectrometry. Results were evaluated with multivariate data analysis and ANOVA. Bread fermented at a high temperature (32°C) had higher peak areas of the Maillard reaction products 2‐furancarboxaldehyde, 2‐acetylfuran, 2‐methylpyrazine, and phenylacetaldehyde compared with bread fermented at lower fermentation temperatures. Bread fermented at low temperatures (8 and 16°C) was characterized by having higher peak areas of the fermentation products 3‐methylbutanal, 2‐methylbutanal, ethyl acetate, ethyl hexanoate, ethyl propanoate, and 3‐methylbutanol. Fermentation of bread with 6% yeast resulted in a higher peak area of the important fermentation product 2‐phenylethanol. It also reduced the peak areas of important lipid oxidation products. The peak area of 2,3‐butanedione was also relatively higher in bread fermented with 6% yeast compared with lower yeast levels; however, an interaction was seen between the high yeast level and all three fermentation temperatures. In contrast, fermentation with a low yeast level (2%) resulted in bread with relatively higher peak areas of 2‐ and 3‐methylbutanal, as well as (E)‐2‐nonenal and (E,E)‐2,4‐decadienal, which are important lipid oxidation compounds in bread.  相似文献   

9.
Influence of botanical source and gelatinization procedure (autoclaving or boiling) on resistant starch (RS) formation was investigated in starches from wheat, corn, rice, and potato. RS yields did not vary within the same sample but differed among samples with different starch botanical sources. Differences also existed in RS contents in native and retrograded starches. Slight or minor variations in RS values were found after both gelatinization procedures, although no clear pattern was found in the behavior of samples based on gelatinization procedure. The degree of polymerization (DP) of retrograded samples was assigned using high-performance anion exchange chromatography with pulsed amperometric detector (average DP 50–60), with no differences between autoclaved and boiled samples.  相似文献   

10.
甘薯天蛾虫蛹用远天23和远天12蛋白酶水解,当底物鲜虫蛹液12mL(浓度为20%,W/V),添加1%酶液1mL,其适宜的水解条件:pH6~7,50℃水解120min并加热至70℃继续水解30min;远天23的酶解效果优于远天12,添加磷酸(钠)盐和EDTA2Na可增加可溶性含氮物总量,添加VC则无效;底物粗蛋白的提取率为81.2%。文章对虫蛹氨基酸营养液的制作工艺、配方及产品质量要求等亦做了介绍。  相似文献   

11.
Gluten‐free breads, which are composed of gluten‐free flours, starch, and hydrocolloids, differ from wheat and rye breads in relation to texture, volume, and crumb structure. Moreover, the dietary fiber content is lower compared with wheat or rye breads. Cereal isolates of lactic acid bacteria frequently produce oligo‐ and homopolysaccharides from sucrose, which can improve the nutritional and technological properties of gluten‐free breads as prebiotic carbohydrates and hydrocolloids, respectively. Sorghum sourdough was fermented with Lactobacillus reuteri LTH5448 or Weissella cibaria 10M, which synthesize fructooligosaccharides (FOS) and levan, and isomaltooligosaccharides and dextran, respectively. The gluten‐free bread was produced with 14% sourdough addition. L. reuteri LTH5448 formed FOS and 1.5 g of levan/kg DM in quinoa sourdoughs. FOS were digested by the baker's yeast during proofing, and the levan could be qualitatively detected in the bread. W. cibaria 10M produced >60 g of isomaltooligosaccharides/kg DM and 0.6 g of dextran/kg DM, which could still be detected in the bread. Breads prepared with W. cibaria 10M were less firm compared with breads prepared with L. reuteri LTH5448 or a FOS and levan‐negative mutant of L. reuteri LTH5448. The addition of sourdoughs fermented with oligo‐ and polysaccharide forming starter cultures can increase the content of prebiotic oligosaccharides in gluten‐free breads.  相似文献   

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13.
《Cereal Chemistry》2017,94(1):2-10
Processing of pulses (peas, beans, lentils, chickpeas, and faba beans) is necessary to reduce or eliminate the antinutrient compounds. Conventional processing including soaking, dehulling, boiling, and pressure cooking as well as germination and fermentation reduce the levels of phytate, protease inhibitors, phenolics, condensed tannins, lectins, and saponins. Recent research has investigated how innovative processes such as extrusion, microwave heating, micronization, and irradiation affect the antinutrient content. Germination tends to be most effective at reducing phytate levels, regardless of pulse type. Mixed results on the effectiveness of extrusion, microwave heating, and micronization have been reported. More work is needed to understand how processing of consumer‐ready foods containing pulse ingredients affects levels of antinutrient compounds.  相似文献   

14.
为了探索氨基酸作为明胶膜增塑剂的潜力,本试验研究了不同氨基酸(脯氨酸、亮氨酸、谷氨酸、丝氨酸和甲硫氨酸)对明胶膜厚度、机械性能、水蒸气透过率、透光率、颜色以及结构等的影响。结果表明,与对照组相比,除了甲硫氨酸外,其余的氨基酸都能增加明胶膜柔韧性;除了脯氨酸外,其余的氨基酸都增加了明胶膜的黄度值,并降低了明胶膜透光率和透明度;而添加脯氨酸的明胶膜的柔韧性最好、具有更好的表观特征,表面光滑紧致,同时具有更高的透明度、透光率和柔韧性。根据傅里叶变换红外光谱和二级结构分析发现,添加脯氨酸、丝氨酸和甲硫氨酸能通过氢键与明胶相互作用,降低明胶的无规则卷曲结构含量,增加β-折叠和β-转角结构含量。综合分析认为,脯氨酸可以作为明胶膜的天然增塑剂。本研究结果为增塑剂在明胶膜中的应用提供了新视角。  相似文献   

15.
A study of the influence of raw materials and processing conditions on the hydration kinetic during cooking and overcooking of spaghetti is presented. Water sorption tests on commercially available spaghetti and on three different types of homemade spaghetti were run at 100°C. In particular, the weight, diameter, and length of spaghetti strands were monitored over time for ≈200 min. The spaghetti hydration process was quantitatively resolved into the controlling phenomena (i.e., water diffusion, macromolecular matrix relaxation kinetic, and residual deformation release kinetic) by fitting a novel mathematical model to the experimental data. The different behavior of spaghetti was analyzed for each of the phenomena involved during hydration. Results suggest that processing conditions highly influence the quality of spaghetti with respect to raw materials.  相似文献   

16.
Gluten-glycerol dough was extruded under a variety of processing conditions using a corotating self-wiping twin-screw extruder. Influence of feed rate, screw speed, and barrel temperature on processing parameters (die pressure, product temperature, residence time, specific energy) were examined. Use of flow modeling was successful for describing the evolution of the main flow parameters during processing. Rheological properties of extruded samples exhibited network-like behavior and were characterized and modeled by Cole-Cole distributions. Changes in molecular sizes of proteins during extrusion were measured by chromatography and appeared to be correlated to molecular size between network strands, as derived from the rheological properties of the materials obtained. Depending on operating conditions, extrudates presented very different surface aspects, ranging from very smooth-surfaced extrudates with high swell to completely broken extrudates. The results indicated that extrudate breakup was caused by increasing network density, and some gliadins may have acted as cross-linking agents. Increasing network density resulted in decreasing mobility of polymeric chains, and “protein melt” may no longer have been able to support the strain experienced during extrusion through the die. Increasing network density was reflected in increased plateau modulus and molecular size of protein aggregates. Increasing network structure appeared to be induced by the severity of the thermomechanical treatment, as indicated by specific mechanical energy input and maximum temperature reached.  相似文献   

17.
An attempt was made to evaluate gluten structural changes in refined and whole wheat pasta from hard white winter wheat to elucidate the impact of whole wheat components on the formation and structure of the gluten network in pasta. Attenuated total reflectance–FTIR spectroscopy was used to track gluten secondary structure through most of the major steps in pasta processing: raw material, mixing, drying, and cooking. Protein solubility, accessible thiols, and SDS‐PAGE data were also collected to provide additional information on the nature of protein interactions and network composition. Few secondary structural differences were observed between refined and whole wheat flours from hard white wheat. However, mixing induced a significant shift to β‐sheet structures in refined dough that was not equally matched by whole wheat dough. Drying under both high temperature, short time (HT) and low temperature, long time (LT) conditions resulted in a reversion to structural distributions similar to those for flour in both pastas. However, greater protein denaturation in HT samples was indicated by lower protein solubility also in the presence of denaturants and disulfide reducing agents. Cooking generated a substantial increase in β‐sheet structures for both pasta systems. This structure was greatest in refined and LT samples. Thiol accessibility data indicate the presence of a highly aggregated, compact gluten network in refined pasta, mostly driven by hydrophobic association. Conversely, the network in whole wheat pasta was more loosely associated and dependent on disulfide bonding, both of which fit well with the secondary structural data.  相似文献   

18.
The processing and quality of wheat flour tortillas prepared with partial waxy and normal flour were evaluated. Control procedures and formula were utilized with water absorption varied to obtain machineable doughs. Amylose content was lower in most partial waxy compared with normal wheats. The type of wheat starch did not affect most dough properties or tortilla diameter. Tortilla height and opacity were adversely affected by the decreased amount of amylose in partial waxy wheats. Sufficient leavening reactions occurred early in baking (after 10 sec) to yield an opaque disk, but some baked tortillas lost opacity and become partially transparent after baking. Starch gelatinizes, disperses, and retrogrades concurrently with the leavening reaction during the short (<30 sec) baking time. Amylose functionality during baking and cooling appears to be involved in the retention of air bubbles in tortillas.  相似文献   

19.
氨基酸螯合微量元素肥料在小麦和后作水稻上的效果   总被引:3,自引:1,他引:3  
氨基酸螯合微量元素肥料是一种新型微肥,经过连续盆栽小麦和水稻(收麦后)试验,结果表明,氨基酸螯合微量元素肥料的肥效及有效性明显优于无机微肥,不仅能改善小麦相关生物性状,而且能改善其营养品质,提高小麦籽粒的蛋白质含量和淀粉含量以及稻粒的淀粉含量。氨基酸螯合微量元素肥料用量少,成本低,肥效显著,宜在生产中推广。  相似文献   

20.
研究了培养基(NCSU23和SOF)和添加氨基酸对猪孤雌激活胚胎体外发育的影响,以探明猪早期胚胎体外培养的最佳体系。实验结果表明,在高氧(5%CO2的空气)或低氧环境(5%CO2:7%O2:88%N2)中,猪的孤雌发育胚胎培养在添加氨基酸的合成输卵管液(SOFaa)中其囊胚发育率显著低于NCSU23培养液;但培养液中添加氨基酸能显著提高卵裂率,培养后期去除氨基酸可减小氨基酸造成的不良影响。胚胎培养早期(前两天)添加氨基酸,不能提高囊胚发育率和囊胚细胞数。  相似文献   

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