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1.
Seed Protein Concentrates (SPC) of 6 species ofCrotalaria were extracted and the extractabilities of SPC, total N and protein N determined. SPC of high yielding species (C. juncea) was analysed for the contents of amino acids, ash, phosphorus, sugar, starch, fibre and calories, as well as forin vitro digestibility. Results indicate the promising potential ofC. juncea for SPC yield.  相似文献   

2.
Seed protein concentrates (SPC) were extracted from 4 leguminous species and the extractabilities of total N (nitrogen), protein N and SPC determined. In addition, composition, calorie value andin vitro enzymatic digestibility of these SPCs was analysed. Results indicate the promising nutritional potential of these SPCs.  相似文献   

3.
Leaves are, and will probably remain, an important dietary source of carotene (provitamin A). There is enough of it in extracted leaf protein (LP) to make that a useful source. carotene is rapidly destroyed when LP, especially from young leaves, is preserved with salt. Destruction can be partly prevented by avoiding contamination with iron during preparation, by coagulating LP by heating rather than acidification, and by treatment with chelating agents. The unsaturated fatty acids in leaf lipids seem not to be involved in the destruction.  相似文献   

4.
Chromolaena odorata (Siam weed) has been classified as a weed plant in West Africa. Data from C. odorata foliage after 4, 6, 8, 10 and 12 weeks of regrowth showed that the leaf fraction had a crude protein content above 194 g kg–1 dry matter (DM) and an average leaf to stem ratio of 2·1:1. Chemical analysis of the leaf fraction of an 8‐week‐old regrowth indicated a high crude protein content (258 g kg–1 DM) and a high degradable nitrogen content (60·7 g N kg–1 digestible organic matter), but low neutral‐detergent fibre (331 g kg–1 DM), acid‐detergent lignin (53·1 g kg–1 DM), total extractable phenolic (37·1 g kg–1 DM), extractable tannin (0·72 absorbance at 550 nm) and extractable condensed tannin (1·4 g kg–1 DM) contents. In sacco degradability analysis of the 8‐week‐old regrowth leaf sample showed a high 48 h organic matter (935 g kg–1 DM) and crude protein (953 g kg–1 DM) degradability. The leaf sample had an organic matter degradability of 670 g kg–1 DM as estimated by cumulative gas production in vitro after 24 h incubation. There was little or no phenolic‐related antinutritive factors in C. odorata. Additionally, leaf samples had no effect on rumen protozoa activity estimated as the rate of [14C]leucine Selenomonas ruminantum bacterial protein breakdown. Data from this study suggest that C. odorata leaves are of high nutritive value and might have the potential to be used as a protein supplement to ruminants. There is need for further investigation to test whether C. odorata leaves may have any deleterious effect on the host animal.  相似文献   

5.
This study evaluated the effects of different combinations of added lactic acid bacteria and cellulase applied at two growth stages on chemical composition and in vitro rumen digestibility of Leymus chinensis silage. Fresh grass was harvested at early heading stage (S1) and late heading stage (S2), respectively, and ensiled with five additives: 200 U cellulase (C) kg?1 fresh matter (FM), 1 × 105 colony‐forming units (cfu) Lactobacillus plantarum (LP) g?1 FM, 1 × 105 cfu Lb. casei (LC) g?1 FM, LP+C, LC+C and a control (CK). Four replicates of each treatment were weighed into 5‐L plastic buckets, and the mini silos were stored at ambient temperature (~30°C) for 60 d. Leymus chinensis harvested at S2 showed relatively higher neutral detergent fibre content, coliform bacteria count and lower crude protein content than S1. All additives decreased the pH and ammonia nitrogen (NH3‐N) content of L. chinensis silage (< 0·001) except C. LP+C and LC+C decreased fibre content and increased water‐soluble carbohydrate content (< 0·001). The silages were further anaerobically incubated in vitro at 39°C for 48 h with buffered rumen fluids of lactating cows. Leymus chinensis harvested at S2 showed lower in vitro dry‐matter disappearance, NH3‐N, total volatile fatty acid (VFA) content and higher average gas production rate (< 0·05) than S1. In conclusion, Leymus chinensis should not be harvested too late. Compared with other treatments, a combination of Lb. casei (LC) with cellulase resulted in better fermented silage, but further testing is needed to confirm its efficacy.  相似文献   

6.
In a study conducted on the extraction of protein from the leaves of 30 freshwater aquatic plants, the highest standing crop fresh yield was found inTypha latifolia (2650g/m2). The Bio-Medical Data Processing (BMDP)K-means clustering program withK=2 showed that 11 of the 30 plants had a high protein nitrogen extractability as well as a high nitrogen content of the extracted protein. Among these, leaf protein fromAllmania nodiflora had the highest content of crude protein (62.7%) and β-carotene (782.4 μg/g). Leaf protein prepared fromHygrophila spinosa, Ottelia alismoides andPolygonum barbatum had low in-vitro digestibility. The levels of alkaloids and polyphenols were lower in the extracted protein compared to that present in the original leaf sample.  相似文献   

7.
《Plant Production Science》2013,16(4):360-366
We examined biomass dry matter and nutrient uptake of live plant parts, leaf area index, and litter of winged bean (Psophocarpus tetragonolobus) and velvet bean (Mucuna pruriens) 12, 18, 24 and 30 weeks after sowing (WAS). The two plants had similar leaf and stem+petiole biomasses. At 30 WAS winged bean had a significantly lower pod yield than velvet bean. Between 18 and 30 WAS, winged bean produced less litter than velvet bean due to differences in growth stages. The total mulch of live parts and litter of winged bean and velvet bean completely covered the ground by 18 and 12 WAS, respectively. Compared to velvet bean, the leaf and stem+petiole of winged bean had a significantly higher N concentration; significantly higher N uptake at 24 and 30 WAS; significantly lower C/N ratio; and significantly higher P, K and Mg concentrations. In winged bean, P uptake was significantly higher in the leaf at 30 WAS and in the stem+petiole at all harvesting times. The total biomass of the leaf, stem+petiole and litter of winged bean was 317–561 g DM m-2, and their N content was 12.3–17.7 g m-2. The total biomass of live parts and litter of winged bean might be sufficient to suppress weeds and increase soil N. Winged bean is an appropriate legume cover crop and green manure due to its longer growing period and superior ground-covering ability and high N input.  相似文献   

8.
《Plant Production Science》2013,16(1):151-154
Abstract

The effect of nitrogen (N) application rates at active tillering and anthesis on grain yield and protein content of a bread wheat cultivar, ‘Minaminokaori’, was examined in the field study conducted in Fukuoka, Japan. Number of spikes, leaf area index (LAI), and SPAD value at anthesis increased significantly (P < 0.05) with increasing N application rate at active tillering. Grain yield also increased significantly (P < 0.05) because of the increased number of spikes. However, grain yield did not increase significantly (P > 0.05) with increasing N application rate at anthesis. The slope of the relationship between N application rate at active tillering and grain yield was about 3 times that of the relationship between N application rate at anthesis and grain yield. These results indicate that N application at active tillering is more effective than N application at anthesis for increasing grain yield. Increasing N application rate at active tillering and anthesis generally increased grain protein content. However, the slope of the relationship between N application rate at anthesis and grain protein content was about 2 times that of the relationship between N application rate at active tillering and grain protein content. These results indicate that N application at anthesis is more effective than N application at active tillering for increasing grain protein content. The interaction between N application rates at active tillering and anthesis was significant (P < 0.05) for grain protein content. With the application of 4 g N m–2 at active tillering, grain protein content increased linearly at a rate of about 0.5% per 1 g N m–2 (from 10.9% to 14.0%) with increasing N application rate (from 0 to 6 g N m–2) at anthesis. However, the rate of increase in grain protein content with increasing N application rate at anthesis was greater with 0 g N m–2 at active tillering than that with 4 g N m–2 at active tillering, whereas that with 8 g N m–2 at active tillering was smaller than that with 4 g N m–2 at active tillering. Application of 8 g N m–2 at tillering resulted in the highest SPAD value at anthesis; this was followed by the results for 4 and 0 g N m–2. Therefore, the SPAD value may be an important trait to decide N application rate at anthesis.  相似文献   

9.
《Plant Production Science》2013,16(4):419-426
Abstract

Soybean requires more nitrogen (N) than gramineous crops because it accumulates a large amount of N in seeds, and its photosynthetic rate per leaf N is low. The supernodulating genotype Sakukei 4 has a superior symbiotic N2 fixation capability, and thereby is potentially high-yielding. In our previous study, Sakukei 4 was characterized by having a superior ability to maintain high leaf N content and high photosynthetic rate. The objectives of this study were to know photosynthetic characteristics of Sakukei 4 in detail, especially, the responses to CO2 concentration and light intensity, and to elucidate how the photosynthetic characteristics of Sakukei 4 are associated with the amounts of photosynthesis-related N compounds (chlorophyll and Rubisco). The three genotypes (Sakukei 4 - supernodulating cultivar derived from Enrei, Enrei - normally nodulating cultivar, En1282-non-nodulating line derived from Enrei) were grown at various N levels in this study. The CO2 exchange rate (CER) in Sakukei 4 was higher than, or equal to that in Enrei at wide ranges of CO2 concentrations (150-700 μmol mol-1) and light intensities (200-1,500 μmol m-2 s-1 PPFD). Sakukei 4 had higher leaf N (Nl), chlorophyll (ChlL) and Rubisco (RubL) contents per leaf area, but lower chlorophyll and Rubisco contents per leaf N content (ChlL/Nl, RubL/Nl) than Enrei. The specific leaf weight (SLW) and leaf area trended to be lower in Sakukei 4 than in Enrei. These results indicate that the superior photosynthetic rate in Sakukei 4 is attributed to higher total N, chlorophyll and Rubisco contents per leaf area, but not to high rate of allocation of total N to these N compounds.  相似文献   

10.
为了解小麦叶片衰老与缺氮诱导及碳氮平衡之间的关系,以两个缺氮衰老响应敏感品种(周麦24和运旱618)和两个缺氮衰老响应不敏感小麦品种(衡观35和西农979)为材料,分析了小麦苗期低氮诱导下表征叶片衰老的叶绿素含量、F_v/F_m、净光合速率,以及表征碳氮平衡的全氮和非结构性碳水化合物(可溶性糖、淀粉)比值。结果表明,低氮胁迫后,4个小麦品种叶片的净光合速率、叶绿素含量和F_v/F_m显著降低,说明低氮诱导和加速了小麦叶片的衰老,而缺氮衰老响应敏感品种的衰老程度显著高于不敏感品种。缺氮衰老响应敏感和不敏感小麦品种叶片氮含量在低氮胁迫后均显著降低,同时碳累积量(可溶性糖和淀粉含量)均显著升高。进一步分析表明,缺氮诱导的小麦叶片衰老可能并非受独立的氮缺乏和碳累积调控,而可能与碳氮平衡(碳氮比例)有关,即碳氮平衡可能参与了低氮诱导的叶片衰老调控,而缺氮下耐衰老品种的叶片维持碳氮代谢平衡的能力较强。  相似文献   

11.
Panicum maximum is important for cattle production in tropical regions, and it responds well to nitrogen (N) fertilization. Many cultivars have exhibited potential for use in silvopastoral systems, although there is limited information on how different levels of N can influence plant growth and nutritive value under shading. Morphogenetic and structural traits, biomass production and nutritive value of two P. maximum cultivars (Tanzânia and Massai) were investigated under three shading levels (0, 37 and 58%) and four N rates (0, 50, 100 and 150 mg N dm?3). Plants were grown in pots under shade. Leaf and stem elongation rate and leaf blade length increased with shading and in response to N. Tiller density was reduced with shading, but showed a linear increase fashion with N under full sun and moderate shading. Under intense shading, the tillering showed a quadratic response to N. Plant biomass production increased linearly with N under full sun and moderate shade, but it increased quadratically under intense shade. Crude protein (CP) content increased with shade and N and was greater for Tanzânia than Massai under shade. Contents of NDF and ADF were greater for Massai than Tanzânia. Acid detergent insoluble protein was reduced in Tanzânia under shade, but it increased for Massai. It is suggested that the positive shading effect on CP content may not result in increased nutritional value. Although N fertilization was important for increasing biomass production under full sun and moderate shade, it should be avoided under intense shading.  相似文献   

12.
Some nutritional characteristics of cassava (Manihot esculenta) leaf protein concentrates obtained by ultrafiltration were compared with that obtained by acidic thermocoagulation. Protein concentrates did not show noticable differences in their proximal composition and amino acids content. However, higher values of total carotene, available lysine, and in vitro digestibility were found, in contrast with less content of total cyanide in protein concentrates obtained by ultrafiltration. Protein efficiency ratio (PER) values of the leaf protein concentrates obtained by ultrafiltration were higher than those obtained by thermocoagulation, 1.81 and 1.60 respectively. These values increased to 2.30 and 1.90 when the concentrates were mixed with sesame flour, in proportion according to the chemical score of their proteins.  相似文献   

13.
利用玉米叶片SPAD值预测子粒蛋白质含量分析   总被引:1,自引:0,他引:1  
利用深松和深松结合秸秆还田技术,对玉米生长5个关键生育时期的叶片SPAD值进行测定分析,获得叶片SPAD值的变化规律;利用FOSS近红外谷物分析仪获得成熟期玉米子粒蛋白质含量,并建立叶片SPAD值与成熟期子粒蛋白质含量的相关关系.相关分析表明,叶片SPAD递减值与成熟期子粒蛋白质含量呈显著负相关,最佳相关模型为y=14.027-0.203x.叶片SPAD递减值可作为判定成熟期子粒蛋白质含量高低的指标,可利用叶片SPAD值递减值并结合相关模型快速预测玉米子粒蛋白质含量.  相似文献   

14.
The relative quantity of specific proteins, protein subunits, as well as amount and size-distribution of polymeric proteins in wheat kernels may vary due to environmental conditions. In this study, the effect of different nitrogen treatments on polymeric and monomeric proteins in wheat was determined. Two soft white biscuit wheat cultivars, a cracker wheat and a hard red bread wheat were planted under irrigation in a randomized complete block design with three replications in two successive years at six different nitrogen treatments. SE-HPLC was used to determine the amount of monomeric and polymeric proteins, and various quality characteristics were measured after harvesting. The large and small SDS-extractable polymeric proteins were not influenced by different N levels. There was a strong cultivar influence, where some cultivars had a larger reaction to N treatments than others. The later application (at flag leaf stage) of nitrogen did not increase the protein fractions. The total amount of N given seemed to have a greater influence on the protein fractions than the timing of the fertilizer application. The lowest N treatment consistently gave the lowest flour protein content value. There was a strong correlation between flour protein content and large monomeric proteins.  相似文献   

15.
The applicability of the hyperspectral data from the canopy to the prediction of wheat grain quality was assessed for winter wheat. A training experiment and a validation experiment with contrasting nitrogen (N) levels and different cultivars were conducted, respectively, at different locations in Beijing, China. The wheat canopy spectral reflectance over 350–2500 nm, leaf N concentration and chlorophyll (Chl) concentration were measured at different growth stages, and the grain protein content was also determined after harvest. Eight vegetation indices (VIs) were compared relating to leaf N concentration, and the result indicated that the plant pigment ratio (PPR, (R550−R450)/(R550+R450)), a Chl-based index, was most applicable to predict wheat grain protein due to its significant correlation with leaf N concentration at the post-anthesis stage. Based on the relationships among PPR, leaf Chl concentration, leaf N concentration, and grain protein content, the statistical prediction models of grain protein content for Zhongyou9507 (a hard winter wheat) and Jingdong8 (a semi-hard winter wheat) were developed. The root mean square error (RMSE) of the 18 DAA (days after anthesis) model of Zhongyou9507 was 0.175; those of the anthesis model and the 11 DAA model of Jingdong8 were 0.238 and 0.982, respectively. Taking both the precision and accuracy into account, the 18 DAA model of Zhongyou9507 and the anthesis model of Jingdong8 were recommended to predict grain protein content for each cultivar. The result demonstrated that PPR could be used to assess grain quality of winter wheat.  相似文献   

16.
为深入研究磷素在小麦淀粉产量和品质形成过程中的作用,以新疆冬小麦主栽品种新冬20号为试验材料,研究0 kg·hm-2(CK)、105 kg·hm-2(LP)和210 kg·hm-2(HP)3种施磷(P2O5)量对小麦籽粒灌浆特性、淀粉合成关键酶(AGPase和GBSS)活性和基因表达、胚乳可溶性蛋白和淀粉粒结合蛋白含量及谱带特征、胚乳微观特性等的影响。结果表明,籽粒灌浆后期磷肥对粒重的促进作用逐渐增强;低磷(LP)条件下, agp1agp2gbss1gbss2基因表达量显著提高;3个处理下AGPase活性的变化趋势基本一致;籽粒灌浆中期(14~21 d),低磷处理的GBSS活性显著高于CK;不同磷处理对淀粉粒结合蛋白和胚乳可溶性蛋白含量的影响显著,但对蛋白谱带特征的影响较弱。扫描电镜结果显示,不同磷处理的胚乳淀粉粒形态未发生明显变化;与CK和高磷(HP)处理相比,低磷处理下籽粒胚乳横断面蛋白基质较少,淀粉粒与蛋白质结合较疏松。说明常规施磷(低磷)条件下,淀粉合成关键酶基因(agp和gbss)相对表达量提高或酶活性变化可影响籽粒淀粉合成及胚乳中蛋白与淀粉粒的嵌合度,并最终造成粒重的增加和淀粉特性的变化。  相似文献   

17.
With a globally strong interest in bio‐based products such as fuels and chemicals, a feasible source of protein for the industry with positive economic impacts could be from leaves. However, more knowledge is needed on how to improve the content of extractable protein. Grasses and legumes have a high content of protein with a favourable amino acid composition. The extractable true protein was estimated at two harvest dates in leaf and stem of the legume species white clover (Trifolium repens L.), red clover (Trifolium pratense L.) and lucerne (Medicago sativa L.) and the grass species perennial ryegrass (Lolium perenne L.) and tall fescue (Festuca arundinacea L.) using the Cornell Net Carbohydrate and Protein System. Extractable true protein was more concentrated in the leaf than in the stem of all the species. Easily extractable true protein in the leaf constituted 63%–68% and 54% of crude protein in legumes and grasses respectively. If the cell wall‐bound true protein in the leaf can be extracted, concentration of extractable true protein may increase by 7%–14% and 21%–26% of crude protein in legume and grass respectively. Legume leaf could be superior to grass leaf for protein production in a biorefinery due to higher extractable true protein both on a mass basis and per hectare. In white clover leaf, a significant decline in concentration of extractable true protein with maturity was simultaneous with a substantial increase in extractable true protein per hectare.  相似文献   

18.
The objective of this study was to develop a mechanistic model for simulating the genotypic and environmental variation in rice growth and yield based on measured plant N accumulation. The model calibrations and evaluations were conducted for rice growth and yield data obtained from a cross-locational experiment on 9 genotypes at 7 climatically different locations in Asia. The rough dry grain yield measured in the experiment ranged from 71 to 1044 g m−2 over the genotypes and locations. An entire process model was developed by integrating sub-models for simulating the processes of leaf area index development, partitioning of nitrogen within plant organs, vegetative biomass growth, spikelet number determination, and yield. The entire process model considered down-regulation of photosynthesis caused by limited capacity for end-product utilization in growing sink organs by representing canopy photosynthetic rate as a function of sugar content per unit leaf nitrogen content. The model well explained the observed genotypic and environmental variation in the dynamics of above-ground biomass growth (for validation dataset, R2 = 95), leaf area index development (R2 = 0.82) and leaf N content (R2 = 0.85), and spikelet number per unit area (R2 = 0.67) and rough grain yield (R2 = 0.66), simultaneously. The model calibrations for each sub-model and the entire process model against observed data identified 10 genotype-specific model parameters as important traits for determining genotypic differences in the growth attributes. Out of the 10 parameters, 5 were related to the processes of phenological development and spikelet sterility, considered to be major determinants of genotypic adaptability to climate. The other 5 parameters of stomatal conductance, radiation extinction coefficient, nitrogen use efficiency in spikelet differentiation, critical leaf N causing senescence, and potential single grain mass had significant influence on the yield potential of genotypes under given climate conditions.  相似文献   

19.
为准确估算冬小麦旗叶光饱和点的范围,采用Li-6400-40荧光探头提供不同光合有效辐射强度,同步测量了不同品种(系)、不同时期(抽穗期、开花期和灌浆期)、不同CO2浓度及不同施氮量下小麦旗叶的气体交换和荧光参数。结果表明,运用直角双曲线修正模型拟合的饱和光强与实际观测值较为接近。外界CO2浓度和施氮量对小麦旗叶光饱和点具有较大影响,低CO2浓度(300 μmol·mol-1)和低施氮量(70 kg·hm-2)下光饱和点均比较低;而品种(系)间和测定时期间小麦旗叶光饱和点整体差异不明显。正常条件下,小麦旗叶的光饱和点整体集中在 1 700~2 000 mol·m-2·s-1范围,远高于目前普遍认为的1 200 mol·m-2·s-1,这与小麦叶片的阳生特点及实际观测结果相一致。早期广泛采用的老版本光合助手(Photosynthesis Assistant)的拟合结果明显低于观测值(P<0.05)。综合试验结果推测,早期光饱和点的研究结果偏低可能与测量CO2浓度、氮素营养以及所用的拟合模型等因素有关。  相似文献   

20.
杂交水稻始穗期氮钾营养对剑叶生理特性的影响   总被引:13,自引:0,他引:13  
 采用盆栽试验研究了杂交水稻汕优63在施基肥的基础上,始穗期供给 NK营养对剑叶生理特性的影响。施用NK,可促进剑叶叶绿素含量、光合速率、蔗糖磷酸合成酶(SPS)、过氧化物酶(POX)、超氧物歧化酶(SOD)、硝酸还原酶(NR)活性提高,呼吸速率下降,增加剑叶的可溶性糖和可溶性蛋白含量及根系活力,加速14C同化物从剑叶的输出,提高14C同化物在稻穗的分布积累及输入积(IAP)。讨论了始穗期共施NK营养提高结实率、谷粒充实度及稻谷产量的良好效果  相似文献   

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