共查询到20条相似文献,搜索用时 15 毫秒
1.
Summary twenty seven field experiments were conducted to determine if there were differences between five barley cultivars in their ability to utilize soil nutrients. There were significant differences among cultivars in yield of grain and in concentration of all macro and micro nutrients examined in both the whole plant and grain.Gateway ranked the highest for the concentration of Na, Mn, and Cu in the whole plant and was among the cultivars with highest concentration of Ca, Fe, and Zn. Centennial had generally the lowest concentration of all the nutrients determined in the whole plant. For the concentrations of Na, Mg, and Cu in grain Gateway ranked highest, but ranked third for the concentrations of K, Ca, Fe, Mn, and Zn in grain. Galt had the highest K and Mg concentration and lowest Mn, Cu and Zn concentration in grain. Except for K concentration in grain, Centennial had the lowest concentrations of all other cationic nutrients in grain.Yield of grain rather than nutrient concentration was the most important criteria in determining the ranking of nutrient yields per hectare. Because of its high grain yield, Bonanza produced the largest yield of micronutrient cations and was second to Galt in production of macronutrient cations, although it was lowest in macronutrient cation concentration. Similarly, Bonanza and Galt had the lowest protein concentration, but produced the highest yield of protein per hectare.The implications for animal nutrition of different levels of nutrients between cultivars are discussed. 相似文献
2.
M. Haridasan 《Plant and Soil》1982,65(2):265-273
Summary Among thirty species belonging to seventeen families common in the cerrado region of central Brazil, eight species belonging to three families were found to accumulate aluminium in their leaves in considerable amounts (4,310 to 14,120 mg/kg on dry weight basis) from a dark red latossol which is strongly-acid and low in available nutrient cations. The aluminium-accumulating species areMiconia ferruginata (DC.) Cogn.,Miconia pohliana Cogn. (Melastomataceae);Palicourea rigida H. B. K. (Rubiaceae);Qualea grandiflora Mart.,Qualea multiflora Mart.,Qualea parviflora Mart. (Vochysiaceae);Vochysia elliptica (Spr.) Mart., andVochysia thyrsoidea Pohl (Vochysiaceae). High levels of aluminium in the leaves of these plants were not associated with low foliar levels of calcium, magnesium, potassium, iron, manganese, zinc, or phosphorus as compared to the other species which do not accumulate aluminium. In spite of the low pH and the low base saturation of the soil the aluminium-accumulating species seem to have an efficient mechanism for absorbing all cations from the soil. 相似文献
3.
The uptake of mineral nutrients from two media with different mineral composition, a classical MSA medium and a modified MH2 medium, by Saponaria officinalis (soapwort) cells was studied over a growth cycle of 14 days, by continuous measurement of mineral consumption without opening the culture flasks. The mineral composition of the MH2 medium was found to be better suited to S. officinalis cells. Culture on MSA medium showed that copper is probably a factor limiting growth, that phosphate is rapidly exhausted from this medium, that its strong ammonium concentration is antagonistic to the absorption of potassium and, lastly, that sodium and chlorine may be considered as non-essential elements. Received: 13 March 1998 / Revision received: 9 June 1998 / Accepted: 1 July 1998 相似文献
4.
Summary No differences were found among the five cultivars studied in the relationships between soil chemical properties and crop concentrations or uptake of macro and micro nutrient cations. Soil pH was significantly correlated with both the concentration and yield of most of the cations from grain of all cultivars with no differences between cultivars determined. None of the cultivars showed significant relationships between the concentration of a nutrient element in the whole plant or in the grain and the available nutrient determined from the soil. The degree of association between the concentration of a given cation in the whole plant and in grain was generally small and, in many cases insignificant. Those cations showing strong relationships were Na, Mn, and Zn. These relationships were not found to differ between cultivars.Stepwise regression analysis showed pH to be the dominant factor determining the composition of whole plants and grain. Addition of soil available nutrients to the equation resulted in slight reductions in the sums of squares.Scientific Paper No. 489, Lacombe be Research Station, Research Branch Agriculture Canada. 相似文献
5.
Muhammad Mehboob Hassan Khan Niaz Ahmed Umber Ghafoor Muqarrab Ali Muhammad Arif Ali Muhammad Irfan Shabir Hussain Shah Fahad Vibhor Agarwal Shams H. Abdel-Hafez Reham Ali Syed Mohammed Basheeruddin Asdaq Nadiyah M. Alabdallah Ali Tan Kee Zuan Subhan Danish Rahul Datta 《Saudi Journal of Biological Sciences》2022,29(3):1869-1880
Micronutrient deficiency in the soil is one of the major causes of mango fruit and yield's poor quality. Besides, the consumption of such a diet also causes a deficiency of micronutrients in humans. Boron deficiency adversely affects the flowering and pollen tube formation, thus decreasing mango yield and quality attributes. Soil and foliar application of B are considered a productive method to alleviate boron deficiency. A field experiment was conducted to explore the Boron most suitable method and application rate in mango under the current climatic scenario. There were nine treatments applied in three replications. The results showed that application of T8 = RD + Borax (75 g plant -1 as a basal application) + H3 BO3 (0.8% as a foliar spray) and T9 = RD + Borax (150 g plant -1 as a basal application) + H3 BO3 (0.8% as a foliar spray) significantly enhanced the nitrogen, potassium, proteins, ash, fats, fiber, and total soluble solids in mango as compared to the control. A significant decrease in sodium, total phenolics contents, antioxidant activity, and acidity as citric acid also validated the effective functioning of T8 = RD + Borax (75 g plant -1 as a basal application) + H3 BO3 (0.8% as a foliar spray) and T9 = RD + Borax (150 g plant -1 as a basal application) + H3 BO3 (0.8% as a foliar spray) as compared to control. In conclusion, T8 = RD + Borax (75 g plant -1 as a basal application) + H3 BO3 (0.8% as a foliar spray) and T9 = RD + Borax (150 g plant -1 as a basal application) + H3 BO3 (0.8% as a foliar spray) is a potent strategy to improve the quality attributes of mango under the changing climatic situation. 相似文献
6.
Mohammad Reza Asgharipour Hamid Reza Azizmoghaddam 《Saudi Journal of Biological Sciences》2012,19(4):441-449
In this study, the effect of irrigation with raw or diluted municipal sewage effluent accompanied by foliar micronutrient fertilizer sprays was examined on the growth, dry matter accumulation, grain yield, and mineral nutrients in foxtail millet plants. The experimental design was a split plot with three irrigation sources: raw sewage, 50% diluted sewage, and well water comprising the main treatments, and four combinations of Mn and Zn foliar sprays as sub-treatments that were applied with four replications. The experiment was conducted in 2009 at the Zabol University research farm in Zabol, south Iran. The applied municipal sewage effluent contained higher levels of micronutrients and macronutrients and exhibited greater degrees of electrical conductivity compared to well water. Because of the small scale of industrial activities in Zabol, the amount of heavy metals in the sewage was negligible (below the limits set for irrigation water in agricultural lands); these contaminants would not be severely detrimental to crop growth. The experimental results indicated that irrigation of plants with raw or diluted sewage stimulates the measured growth and productivity parameters of foxtail millet plants. The concentrations of micronutrients and macronutrients were also positively affected. These stimulations were attributed to the presence of high levels of such essential nutrients as N, P, and organic matter in wastewater. Supplied in sewage water alone, Mn and Zn were not able to raise the productivity of millet to the level obtained using fertilizers at the recommended values; this by itself indicated that additional nutrients from fertilizers are required to obtain higher levels of millet productivity with sewage farming. Despite the differences in nutrient concentrations among the different irrigation water sources, the micronutrient foliar sprays did not affect the concentrations of micronutrients and macronutrients in foxtail millet plants. These results suggested that municipal sewage effluent could be utilized efficiently as an important source of water, and that the nutrients used in growing foxtail millet with sewage water irrigation did not have any significant harmful effect on crop productivity. In contrast, the nutrients proved beneficial to soil fertility and millet productivity and quality. 相似文献
7.
8.
Accumulation of nutrients by eucalyptus seedlings from acidic and calcareous soils of the cerrado region of Central Brazil 总被引:1,自引:0,他引:1
M. Haridasan 《Plant and Soil》1985,86(1):35-45
Summary The accumulation of nutrients by seedlings ofEucalyptus grandis andE. saligna from a latosol and two other fertile soils was compared. Both species performed well in a calcareous soil and an acidic but fertile gallery forest soil but not in the dystrophic latosol.E. grandis accumulated more nutrients from the calcareous soil thanE. saligna. In the other two soils these two species showed similar growth and nutrient accumulation. In spite of the high acidity, manganese toxicity did not seem to be a limiting factor in the latosol or the gallerty forest soil. Correlations among the shoot concentrations were not always the same as those among the total contents of the nutrients in the aerial biomass. 相似文献
9.
A fundamental puzzle about human behavior is low investment in preventive health inputs. Present-biased preferences have frequently been put forth as a theoretical explanation for this, but with limited empirical evidence supporting it, especially in developing countries. We extend our previous analysis of a field experiment testing advertising strategies to increase demand for a potentially life-saving preventive health technology, voluntary medical male circumcision. Offering compensation of US$10 conditional on a complement to the procedure, a short counseling session at a providing clinic, tripled uptake of the procedure. This is consistent with the idea that subsidizing a complement encouraged procrastinating men with latent demand to invest in preventive health. In addition, framing the basic advertisement using the statement “Are you tough enough?” doubled uptake. 相似文献
10.
Recent clinical research has studied weight responses to varying diet composition, but the contribution of changes in macronutrient intake and physical activity to rising population weight remains controversial. Research on the economics of obesity typically assumes a “calories in, calories out” framework, but a weight production model separating caloric intake into carbohydrates, fat, and protein, has not been explored in an economic framework. To estimate the contributions of changes in macronutrient intake and physical activity to changes in population weight, we conducted dynamic time series and structural VAR analyses of U.S. data between 1974 and 2006 and a panel analysis of 164 countries between 2001 and 2010. Findings from all analyses suggest that increases in carbohydrates are most strongly and positively associated with increases in obesity prevalence even when controlling for changes in total caloric intake and occupation-related physical activity. Our structural VAR results suggest that, on the margin, a 1% increase in carbohydrates intake yields a 1.01 point increase in obesity prevalence over 5 years while an equal percent increase in fat intake decreases obesity prevalence by 0.24 points. 相似文献
11.
This paper is the first attempt to produce diatom-based transfer functions for the northern tropical Americas. A dataset of 53 modern diatom samples and associated hydrochemical variables from 31 sites in the volcanic highlands of central Mexico is presented. The relationship between diatom species distribution and water chemistry is explored using canonical correspondence analysis (CCA) and partial CCA. Variance partitioning indicates that ionic strength and ion type both account for significant and independent portions of this variation. Transfer functions are developed for electrical conductivity (r2 = 0.91) and alkalinity (as a percentage of total anions) (r2 = 0.90), reflecting ionic strength and ionic composition respectively. Prediction errors, estimated using jack-knifing, are low for the conductivity model, but the carbonate transfer function performs less well. This study highlights the potential for diatom-based quantitative palaeoenvironmental reconstructions in central Mexico. However, a number of key diatom species found in fossil material are not represented in the modern flora. Sampling of additional sites may resolve this, but it is thought that the lack of modern analogues may reflect the high degree of anthropogenic disturbance in many of the catchments. This highlights the problem of trying to reconstruct pre-disturbance environmental changes in highly modified ecosystems. One possible solution is to merge the central Mexican data with the African dataset, which includes sites of similar chemical composition, but which have not suffered the same degree of disturbance. 相似文献
12.
Piperata BA Spence JE Da-Gloria P Hubbe M 《American journal of physical anthropology》2011,146(1):1-13
The goal of this longitudinal study was to assess the impact of economic change and increased market integration on subsistence strategies, living conditions, growth, and nutritional status of Ribeirinhos living in the rural Amazon, Brazil. Data on weight, height, skinfolds, and circumferences, as well as data on economic strategies and living conditions were collected from 469 individuals in 2002 and 429 in 2009. Of these, 204 individuals were measured on both occasions. Independent and paired t‐tests were used to identify changes in nutritional status over time in the larger sample and smaller, longitudinal subsample, respectively. Multiple linear regressions were used to examine the relationship between changes in economic/living conditions and nutritional status in the longitudinal subsample. Results indicate modest improvements in linear growth (HAZ) and among male children the observed increase was related to enrollment in the Brazilian conditional cash transfer program, Bolsa Família (P = 0.03). In terms of short‐term measures of nutritional status, we found a significant increase in ZTSF and a reduction in ZUMA in most age/sex groups. Among subadults, there was a negative relationship between ZUMA and access to electricity (P = 0.01) and positive relationship between ZUMA and the sale of the açaí fruit (P = 0.04). Significant changes in weight and BMI (P < 0.01) were found among adult females and both were negatively related to household cash income (P = 0.02 and P = 0.03, respectively). Despite significant changes in economic strategies and lifestyle, changes in nutritional status were modest which may be explained by increased food insecurity documented during this early stage of transition. Am J Phys Anthropol, 2011. © 2011 Wiley‐Liss, Inc. 相似文献
13.
Deficiency of micronutrients is considered as the basic cause of health issues. There are a large number of micronutrients to be considered for good health, which are analyzed separately. However, such analyses involve practical as well as methodological complications and it requires construction of an index representing malnutrition of micronutrients. This study proposes copula methodology to categorize malnutrition of micronutrients at household level by combining the dependence structure of various correlated variables. Data of eleven micronutrients are extracted from HIICS- 2015–16 published by Pakistan -Bureau of Statistics. Seven out of the eleven variables are highly correlated, which are considered to construct the index. These include calcium, iron, iodine, zinc, riboflavin, thiamine and phosphorus intakes per capita at household level. Normal probability distribution is found as the best fit to the sample data of all variables. Gaussian copula function is used to derive multivariate probability distribution by combining univariate marginal probability distribution of each micronutrient. The Multivariate distribution of Gaussian copula model is used to calculate cumulative probabilities, which provide a base to categorize households’ malnutrition w.r.t. micronutrients. The results show that 60% households lie in very low or low category of micronutrient intakes, 20% of households fall into medium category while 20% fall into high or very high category of micronutrient consumption. The proposed methodology might be helpful to combine other micronutrients as well as a variety of correlated variables in many other fields having a survey data 相似文献
14.
在借鉴公司现有持有相关研究的基础上,结合我国公立医院实际情况,构建实证模型,以B地区171家二级医院和三级医院2006—2009年数据验证。实证结果表明:公立医院并不像感性认识的那样不重视财务管理,就现金管理来说,医院积极进行现金管理,对其现金持有量进行动态调整,以实现目标现金持有额。以现金持有量满足日常运营的时间判断,公立医院现金持有水平是合理的。 相似文献
15.
《Chronobiology international》2013,30(3):385-392
Rats with ad libitum water and the ability to self-select among three macronutrient-rich diets—carbohydrate (CHO), protein (PRO), and lipid (LIP)—show a circadian rhythmicity in their ingestion. The aim of the present study was to determine whether this circadian rhythmicity is reliable from day to day. Eight rats were offered ad libitum water and a choice of three isoenergetic diet rations providing carbohydrate, protein, and lipid. Water and food intake was recorded every 3 h for 7 days. The reliability of the circadian rhythm of water and food intake was assessed by the Intraclass Correlation Coefficient (ICC) and the test-retest reliability using the Pearson's Correlation Coefficient (r). The results showed that the circadian rhythm of water, CHO, and PRO intake are strongly reliable. However, the circadian rhythm of LIP intake is less reproducible. Among the three reliable parameters—water, CHO, and PRO, the circadian rhythm of water intake was the most reproducible over 7 days. This suggests that water intake may be used as a marker of circadian rhythmicity in ingestive behavior. 相似文献
16.
The concept of photoprotection by dietary means is gaining momentum. Plant constituents such as carotenoids and flavonoids
are involved in protection against excess light in plants and contribute to the prevention of UV damage in humans. As micronutrients,
they are ingested with the diet and are distributed into light-exposed tissues, such as skin or the eye where they provide
systemic photoprotection. β-Carotene and lycopene prevent UV-induced erythema formation. Likewise, dietary flavanols exhibit
photoprotection. After about 10–12 weeks of dietary intervention, a decrease in the sensitivity toward UV-induced erythema
was observed in volunteers. Dietary micronutrients may contribute to life-long protection against harmful UV radiation. 相似文献
17.
目的:通过分析北京市方庄地区儿童全血微量营养素的含量及影响因素,研究探讨微量营养素缺乏的防治措施。方法:2011年1月至12月北京中医药大学东方医院儿科门诊1887例健康体检儿童,收集末梢血,采用原子吸收光谱仪检测全血5种微量营养素铜、锌、钙、镁、铁的含量,并从性别、年龄、季节(月份)方面进行比较分析。结果:全血5种微量营养素含量无性别差异(P0.05),但存在季节差异,4-6月铜、锌含量降低;7-9月钙、镁含量降低;10-12月铁含量降低(P0.05)。全血锌、铁含量存在年龄差异,婴幼儿最低(P0.05)。1887例儿童中,缺乏较多的元素依次为铁(38.8%)、钙(22.3%)、锌(12.8%),其中,4-7岁(17.0%)、7-12岁(21.5%)年龄段组以锌缺乏居多。1岁以内(51.2%)、1-3岁(44.6%)年龄段组以铁缺乏居多。全血铜、锌、钙、铁缺乏无性别差异(P0.05)。全血5种微量营养素缺乏存在季节差异,1-3月镁缺乏明显,4-6月铜、锌缺乏明显,10-12月钙、铁缺乏明显(P0.05)。结论:北京市方庄地区儿童主要存在锌、钙、铁的缺乏,以秋冬季及初春明显。其中婴幼儿以铁缺乏为主,学龄前期及学龄期儿童以锌缺乏为主。应加强对此地区儿童的营养宣教和饮食指导。 相似文献
18.
The present study was carried out to examine the effects of salicylic acid (SA) on growth, activities of antioxidant enzymes and some physio-biochemical attributes in mustard [Brassica juncea (L.) Czern. & Coss.] plants exposed to cadmium (Cd) stress. Increasing concentrations of Cd led to decreased growth, shoot biomass, relative water content (RWC) and rate of photosynthesis (A). SA allayed the adverse effects of Cd on growth, RWC, and A, but the inhibitory effect of Cd on stomatal conductance (gs) and transpiration rate (E) was further promoted due to SA treatment. Cadmium-induced oxidative stress increased proline, lipid peroxidation and electrolyte leakage, but on exposure to SA, these parameters showed a marked decrease. Lower concentrations of Cd caused enhanced Cd transport into the plant. Cadmium suppressed the uptake of macro- and micro-nutrients, but exogenous application of SA restored the capability of plants to accumulate essential elements. SA mitigated the Cd-induced inhibition in the growth of mustard plants. Cadmium-induced increase in the activities of some key antioxidant enzymes, superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), and glutathione reductase (GR) was reduced by the exogenous application of SA. This reflects that SA might have acted as one of the potential antioxidants in mustard plants under Cd stress. 相似文献
19.
《Harmful algae》2013
A toxic bloom of Pseudo-nitzschia spp. was observed in the Alabama coastal waters of the northern Gulf of Mexico (NGOM) in June 2009 that resulted in the accumulation of domoic acid (DA) in fish. The bloom initiated following a large storm event that likely caused increased groundwater discharge 16–20 days prior to peak densities. Eleven sites, located in littoral shoreline waters and inshore embayments spanning the entire Alabama NGOM coastline, were sampled during peak densities to assess Pseudo-nitzschia species composition and toxicity, and associated water-quality parameters. Small fish (0.27–11.9 g body weight) were collected at six of these sites for analysis of DA content. High Pseudo-nitzschia spp. densities (8.27 × 104–5.05 × 106 cell l−1) were detected at eight sites located in the littoral shoreline and particulate DA was detected at six of these littoral sites (48.0–540 pg ml−1). The bloom consisted primarily (>90%) of Pseudo-nitzschia subfraudulenta, a species previously characterized as forming only a minor component of Pseudo-nitzschia assemblages and not known to produce DA. Pseudo-nitzschia spp. were at low densities or not detected at the inshore sites and DA was detected at these sites. Pseudo-nitzschia spp. density varied along an estuarine gradient, with greater densities occurring in the most saline, clear, and nutrient-poor waters. Cell density was strongly and negatively correlated with silicate (Si) concentrations and the ratios of silicate to dissolved inorganic nitrogen and phosphate (Si:DIN and Si:PO4). Cell toxin quota was negatively correlated with phosphate, and strongly and positively correlated with the ratio of total nitrogen to total phosphorus (TN:TP). These relationships are consistent with previous observations that indicate Pseudo-nitzschia spp. density and toxicity are likely to be greater in high salinity, high irradiance, and nutrient-poor waters. DA was detected in 128 of 131 (98%) of the fish collected, which included seven primary and secondary consumer species. This is the first demonstration of trophic transfer of DA in this region of the NGOM, indicating that toxic blooms of Pseudo-nitzschia spp. in Alabama coastal waters have the potential to transfer DA to recreationally and commercially important fish species. 相似文献
20.
The aim of this study was to analyse the dietary zinc, copper and iron intakes in haemodialysis patients and in healthy controls. A statistically significant lower intake of these elements was observed in the patients group. In particular, the copper intake was extremely low in that group, not reaching 40% of the recommended value. 相似文献