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1.
Plant genotypes differ in their uptake, translocation, accumulation, and use of mineral elements. Examples of genotype differences to iron, nitrogen, phosphorus, potassium, calcium, magnesium, manganese, boron, copper, zinc, and molybdenum are discussed. Current knowledge is sufficient to indicate that many crop plants can be improved for the efficient use of mineral elements and better adaptation to mineral stress conditions.  相似文献   

2.
Aims We aim to investigate variations in the resorption efficiencies of 10 mineral nutrients [i.e. nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), zinc (Zn), aluminum (Al), iron (Fe) and copper (Cu)] in leaves of desert shrubs and to explore effects of aridity on resorption efficiency of these nutrients.  相似文献   

3.
Summary This paper describes a factorial experiment which was designed to elucidate the effect of total iron supply and rate of iron supply on the yield of tomato plants. Information was also obtained on the effect of iron supply and leaf age on the concentration of a number of nutrient elements in the leaf tissue.Increasing the total iron supply increases the yield, and the iron concentration in the leaves, while the manganese, phosphorus, sodium, calcium and magnesium decrease in concentration. The young leaves have a lower concentration of iron, manganese, potassium, sodium, calcium and magnesium than the older leaves, while the reverse is true of nitrogen and phosphorus. A slow rate of iron supply decreases the yield and sodium concentration in the leaves but increases the manganese and phosphorus concentrations.Interaction between total iron supply and leaf position affects the manganese, potassium, calcium and magnesium concentrations in the leaves, while the interaction between total-iron level and rate of iron supply affects the phosphorus and calcium concentration in the leaves.  相似文献   

4.
Nowadays there is a resurgence of interest in wild plants for their possible medicinal value in diets, since some epidemiological studies have demonstrated their effectiveness against important diseases. Generally, foods of plant origin contain many bioactive compounds, proteins, energy, vitamins and specific minerals; in addition, the popular wild plant species provide fibre, essential fatty acids and enhance the taste and colour in diets. We studied the nutritional and medicinal potential of leaves of A. subfusiformis and U. urens, collected in Alice, South Africa in November 2006. To asses this we analyzed the phytochemical, antioxidant and antibacterial activities of leaves in acetone, methanol and water extracts, using standard analytical methods. The proximate analysis showed that the leaves of both plant species contained appreciable percentages of moisture; ashes; carbohydrates; crude proteins, lipids and fibres. Elemental analysis of macro and microelements showed higher values for U. urens that contained in decreasing order: iron > manganese > zinc > copper > calcium > potassium > nitrogen > magnesium > phosphorus > sodium, for A. subfusiformis resulted in iron > zinc > manganese > copper > calcium > potassium > nitrogen > magnesium > phosphorus > sodium. Besides, the chemical composition showed higher concentration of alkaloids, saponins and phytates in A. subfusiformis. The extracts also caused 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and 2, 2-azinobis-3 ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activities which were comparable to those of ascorbic acid. The extracts of both plants contained appreciable levels of polyphenols and also caused varied inhibition of some bacterial strains used in this study. When the nutrient and chemical constituents of these plants were compared with recommended dietary allowance (RDA) values, the results revealed that the leaves contain an appreciable amount of nutrients, minerals, and phytochemicals and low levels of toxicants. Since the plants also exhibited some level of antibacterial activities, their use for medicinal purposes is to some extent being justified.  相似文献   

5.
Sub-tropical rainforests in New South Wales are complex, oftenwith more than 30 tree species ha–1. Estimation of nutrientcontents involves obtaining information on the range of nutrientconcentrations both in different species and in different foreststrata. The foliage from the tree and shrub components of an undisturbedforest were analyzed chemically together with the small treeand shrub component of an area logged two years previously.The site had high nutrient availability. All nutrients analyzed(nitrogen, phosphorus, calcium, magnesium, potassium, manganese,aluminium, sodium, zinc, iron, boron and chloride) varied betweenspecies. Some individuals accumulated high concentrations ofspecific nutrients, but an accumulator of one nutrient was notnecessarily an accumulator of any other. Assessment of nutrient concentrations on the basis of foreststrata showed major differences. Nutrients were accumulatedin higher concentrations on a disturbed site than on an undisturbedsite. This has been discussed in relation to nutrient conservationmechanisms after disturbance. Within the undisturbed stand,the large shrub stratum had the highest concentrations of nitrogen,phosphorus, potassium and boron. Mean concentrations of aluminium,sodium and chloride were highest in the small shrub stratum,mainly because several species accumulate these elements. Sub-tropical rainforest, nitrogen, phosphorus, calcium, magnesium, potassium, manganese, aluminium, sodium, zinc, iron, boron, chloride  相似文献   

6.
Summary Spinach plants were grown in nutrient-culture solutions containing reduced levels of all the macro- and micro-nutrient elements except cobalt and chlorine. The rates of photosynthesis (carbon dioxide fixation in the light expressed on a per unit chlorophyll or per unit fresh-weight basis) and respiration (carbon dioxide evolution in the dark expressed on a per unit nitrogen or per unit fresh-weight basis) for whole plants were measured using infra-red gas analysis techniques. Measurements were made when the plants displayed clear symptoms of deficiency relative to control plants. All nutrient deficiencies except iron and molybdenum depressed photosynthesis when chlorophyll was the basis of calculation; manganese-, copper-, phosphorus- and potassium-deficient plants showed the greatest depression. Alternatively when photosynthesis was calculated on a fresh weight basis calcium was the only deficiency which had no affect. Similarly when respiration was calculated on a nitrogen basis all deficiencies except iron, molybdenum and nitrogen result in depressed rates but when respiration was expressed on a fresh-weight basis potassium deficiency resulted in enhanced respiration rates and nitrogen, phosphorus, sulphur, manganese, zinc and molybdenum deficiencies resulted in reduced respiration rates.  相似文献   

7.
The results are given of chemical analyses of leaves collectedover a period of one year from cacao trees in a field trialreceiving fertilizer, shade, and irrigation treatments. Thegreatest variation in concentration of the elements under studywas found to be due to the time of year at which the leaveswere collected. The lowest concentrations of zinc and copperwere found in the leaves collected during the peak of the mainseason crop. The lowest concentrations of manganese, aluminium,and iron were found in leaves collected about a month afterthe end of the main harvest. The levels of most elements rosesharply after the end of the main harvest. The levels of mostelements rose sharply after reaching a minimum, and the maximumlevels were usually reached before completion of flowering forthe next main season crop. The effects of the treatments onthe nutrient levels in the leaves were generally small. Thefertilizer treatment tended to increase the levels of manganese,aluminium, iron, sodium, and zinc and to decrease the levelof boron. The shade treatment tended to increase the levelsof sodium, copper, and zinc and to decrease the levels of manganese,aluminium, and iron. The irrigation treatment had no substantialeffect on the level of any element. The levels of iron, manganese,and boron, were found to be positively correlated with the levelof aluminium.  相似文献   

8.
Effects of silicon on the chemical composition of rice plants   总被引:3,自引:2,他引:1  
Summary Rice plants were grown in nutrient culture solutions. Silicon was supplied to these plants at different rates. The plant samples of early vegetative, vegetative and flowering stages were analysed for nitrogen, phosphorus, potassium, calcium, magnesium, iron, manganese, silicon, protein and carbohydrate contents. The application of silicon generally decreased the nitrogen, protein and potassium content of rice plants. Its application also decreased the iron and manganese contents. The use of silicon resulted in an increase in phosphorus, calcium, magnesium, silicon and carbohydrate contents of rice plants.Reader and Head of the Department of Soil Science, University of Dacca, Dacca, East Pakistan.  相似文献   

9.
The results are given of chemical analyses of leaves collectedover a period of two years from cocoa trees in a field trialreceiving fertilizer, shade, and irrigation treatments. Thegreatest variation in concentration of nutrients in the leaveswas due to the time of year the leaves were collected. The lowestconcentrations of nitrogen, phosphorus, and potassium were foundin the leaves collected during the peak of the main season harvest.The highest levels of these elements were found in leaves collectednear the end or a few weeks after the end of the main harvest.The levels of calcium in the leaves were just opposite, withthe highest levels coinciding with harvest and the lowest levelsoccurring just after the harvest period. The levels of magnesiumshowed no marked variations between seasons. Shade increased the levels of nitrogen, phosphorus, and potassium,and decreased the levels of calcium in the leaves. Fertilizerincreased the levels of nitrogen, phosphorus, calcium, and magnesium,and decreased the level of potassium in the leaves. The effectof irrigation was small, but it decreased the levels of nitrogen,potassium, calcium, and magnesium in the leaves. The levels of nitrogen, phosphorus, and potassium in the leavesover the 21 harvesting times were found to be positively correlatedwith each other, and all three were negatively correlated withthe levels of calcium in the leaves over the same period. Noneof the levels of these four elements was significantly correlatedwith the levels of magnesium in the leaves over the period.  相似文献   

10.
Tomato plants were fed with calcium 45, cobalt 60, copper 64,iron 59, magnesium 28, manganese 54, molybdenum 99, potassium42, sodium 24, tungsten 187, and zinc 65 in sand or water culture.Fresh tissues were then extracted with a series of reagents,and the percentage radioactivity determined in each fraction.Apart from calcium and iron, a measurable proportion of theassimilated activities were found in a form soluble in ethanol:the nature of the soluble cobalt and zinc complexes was investigated.Almost all the elements were removed by treatment with dilutehydrochloric and perchloric acids, but significant amounts ofiron and cobalt were left in the residue.  相似文献   

11.
The effects of low dietary rubidium on plasma biochemical parameters and mineral levels in tissues in rats were studied. Eighteen male Wistar rats, weighing about 40 g, were divided into two groups and fed the diets with or without supplemental rubidium (0.54 vs 8.12 mg/kg diet) for 11 wk. Compared to the rats fed the diet with supplemental rubidium, the animals fed the diet without rubidium supplementation had higher urea nitrogen in plasma; lower rubidium concentration in tissues; lower sodium in muscle; higher potassium in plasma, kidney and tibia, and lower potassium in testis; lower phosphorus in heart and spleen; lower calcium in spleen; higher magnesium in muscle and tibia; higher iron in muscle; lower zinc in plasma and testis; and lower copper in heart, liver, and spleen, and higher copper in kidney. These results suggest that rubidium concentration in tissues reflects rubidium intake, and that rubidium depletion affects mineral (sodium, potassium, phosphorus, calcium, magnesium, iron, zinc, and copper) status.  相似文献   

12.
Inorganic analysis of Ascaridia galli has shown the levels of sodium, potassium, copper, magnesium, calcium, zinc, iron, nitrogen, phosphorus, sulphur, chlorine and cobalt (expressed as percentage of dry weight) to be higher in females than in males.  相似文献   

13.
In this study, the change in the content of the macro and micro elements in the growing wild grazing plant of Calligonum comosum was tracked at the Research and Training Station of King Faisal University in Al-Hassa Governorate, Kingdom of Saudi Arabia. Mineral elements were estimated in aerial parts (plant as a whole, leaves and stem) from January-April 2020. The results showed that the concentration of nitrogen, phosphorus and potassium in the plant as a whole plant > leaves > roots, while the concentrations of calcium, magnesium, manganese, zinc and copper elements in the leaves was higher than other parts whereas the concentrations of these elements of whole plant were higher than the concentrations in roots. The results showed that the plant contents of nitrogen, potassium and zinc were the highest in March, while the concentrations of phosphorus, calcium, iron and copper were in February. The concentrations of magnesium, manganese and copper was the highest in January and April respectively. The values ​​of nitrogen, phosphorous, potassium, calcium, magnesium, iron, manganese, zinc and copper ranged from 11.1 to 18.4 g kg−1, 4.17–2.33 g kg−1, 13.73–18.97 g kg−1, 24.50–28.90 g kg−1, 10.40–12.30 gkg−1, 1500–1677 mg kg−1, 45.45–49.29 mg kg−1, 70.70–177.23 mg kg−1, 16.78–73.46 mg kg−1, respectively. Furthermore, the results exhibited that the lowest values of the elements appeared in the plant roots in April. As well as, the distribution of the elements followed the normal life curve from January to April. Besides that, the evaluated elements satisfy the needs of the grazing animals' life in which this type of plant grows.  相似文献   

14.
Micronutrient status and fertilizer use scenario in India   总被引:1,自引:0,他引:1  
India was dependent on external food supplies in the early 1960s. To meet the growing demand for food, fiber and fuel, high yielding cultivars were introduced. These high yielding crop cultivars were highly responsive to fertilizers. Thus, slowly the soils were exhausted of their nutrients. Application of major nutrients (nitrogen, phosphorus, potassium) became common, therefore the crops started responding to micronutrient fertilizers. Concerted efforts have been made through the All India Coordinated Research Project on Micronutrients to delineate the soils of India regarding the deficiency of micronutrients. At present about 48.1% of Indian soils are deficient in diethylenetriaminepentaacetate (DTPA) extractable zinc, 11.2% in iron, 7% in copper and 5.1% in manganese. Apart from the deficiency of these micronutrients, deficiencies of boron and molybdenum have also been reported in some areas. Areas with multi-micronutrient deficiencies are limited, thus simple fertilizers are sufficient to exploit the potential of crops and cropping systems. Based on the extent of deficiency, cultivated area, and crop removal, the micronutrient fertilizer demand in 2025 is projected using sufficiency and maintenance approaches.  相似文献   

15.
India was dependent on external food supplies in the early 1960s. To meet the growing demand for food, fiber and fuel, high yielding cultivars were introduced. These high yielding crop cultivars were highly responsive to fertilizers. Thus, slowly the soils were exhausted of their nutrients. Application of major nutrients (nitrogen, phosphorus, potassium) became common, therefore the crops started responding to micronutrient fertilizers. Concerted efforts have been made through the All India Coordinated Research Project on Micronutrients to delineate the soils of India regarding the deficiency of micronutrients. At present about 48.1% of Indian soils are deficient in diethylenetriaminepentaacetate (DTPA) extractable zinc, 11.2% in iron, 7% in copper and 5.1% in manganese. Apart from the deficiency of these micronutrients, deficiencies of boron and molybdenum have also been reported in some areas. Areas with multi-micronutrient deficiencies are limited, thus simple fertilizers are sufficient to exploit the potential of crops and cropping systems. Based on the extent of deficiency, cultivated area, and crop removal, the micronutrient fertilizer demand in 2025 is projected using sufficiency and maintenance approaches.  相似文献   

16.
BackgroundSome elements were claimed to play a role in the pathogenesis of congenital heart defects (CHD) and influence the general well-being and health of these children.ObjectivesWe aimed to assess the levels of some elements simultaneously in the blood and teeth samples of children with cyanotic and acyanotic CHD compared with healthy children.MethodsA total of 39 children with CHD (11 with cyanotic and 28 with acyanotic CHD) and 42 age- and sex-adjusted controls were enrolled. Levels of 13 elements, including magnesium, phosphorus, calcium, chromium, manganese, iron, copper, zinc, strontium, cadmium, lead, mercury, and molybdenum, were assessed using inductively coupled plasma mass spectrometry.ResultsChildren with cyanotic and acyanotic CHD had significantly lower teeth calcium and calcium/phosphorus ratio as compared to the controls after adjusting for confounders. The mean blood iron level was found to be significantly higher in the cyanotic CHD group compared to the other groups. In addition, children with acyanotic CHD had significantly higher teeth copper levels, higher blood molybdenum and lower blood magnesium levels compared to the healthy control group. Blood cadmium and mercury levels were found to be significantly elevated in both the cyanotic and acyanotic CHD groups compared to the healthy control group. There were no differences in toxic metal levels of teeth in cases with CHD.ConclusionMonitoring adequate and balanced gestational micronutrient intake might support not only maternal health but also fetal cardiac development and infant well-being. Supplementation of magnesium should be evaluated in patients having CHD.  相似文献   

17.
TRACE-ELEMENT TOXICITIES IN OAT PLANTS   总被引:4,自引:0,他引:4  
Excessive amounts of nickel, cobalt, chromium, copper, zinc, manganese, molybdenum and aluminium in nutrient solutions supplied to oat plants in sand culture produce ( a ) chlorosis and ( b ) other symptoms specific to the element involved. The specific symptoms are distinct for each metal, although those of cobalt and nickel might be confused.
The toxic effects of nickel, cobalt, copper, zinc, manganese and molybdenum are associated with high concentrations of the element in the leaf tissue, but this is not always so with chromium and aluminium.
The toxic effects of nickel, chromium, copper and molybdenum are associated with a reduced nitrogen content of the plant. Nickel, cobalt, chromium, zinc and manganese increase the concentration of phosphorus in the tissue whilst aluminium decreases it, probably to a deficiency level.
Aluminium reduces the intensity of toxic symptoms produced by nickel—probably by reducing the uptake of nickel and phosphorus. Copper effectively reduces the leaf necrosis produced by nickel, but not the nickel content of the leaf tissue; it is suggested that one factor in nickel toxicity may be inhibition of one or more functions of copper. The other elements slightly increase chlorosis and some increase necrosis.
The order of activitjl of the elements in producing chlorosis is found to be Ni>Cu>Co>Cr>Zn>Mo>Mn. This order, which is related to that giving yield reduction and is similar to the order of stability of metal complexes, is discussed in relation to induced iron deficiency.  相似文献   

18.
Two experiments were performed to confirm that boron interacts with calcium, and that this interaction can be modified by dietary magnesium and potassium in the rat. Upon manipulating the dietary variables listed above, it was found that under certain conditions, boron and calcium deprivation similarly affected several variables; for example, they both could be made to elevate plasma alkaline phosphatase activity and to depress femur calcium concentration. Under some dietary conditions, both boron and calcium deprivation affected some variables related to blood or iron metabolism. However, the effects of dietary boron and calcium on spleen weight/body weight ratio, hematocrit, and femur iron concentration generally were not similar. Femur copper, magnesium, phosphorus, and zinc also were affected by an interaction between boron and calcium under some dietary conditions. The findings show that there is a relationship between boron and calcium, but they do not clearly indicate the nature of the relationship. However, the data suggest that boron and calcium act on similar systems in the rat.  相似文献   

19.
Sodium, potassium, calcium, magnesium, manganese, zinc and chloride contents in the blood plasma of calves at parturition have been established to correspond to their levels in blood of cows during their calving period. Iron and inorganic phosphorus contents in calves blood plasma appeared to increase and copper content to be lower in this period as compared to postnatal period. By the third day of postnatal ontogenesis sodium concentration in calves blood decreased, copper level increased and the rest indices of water-salts metabolism in calves and adult animals were alike. Digestion disturbances in the calves were accompanied by changes in levels and magnitude of Na+/K+ ratio, magnesium, iron, copper, manganese and zinc contents in blood, liver and kidneys as well as Ca++/Pi ratio in mitochondria and cytosol of liver and jejunum mucose layer cells in comparison with clinically healthy animals.  相似文献   

20.
The aim of this work is to show and give a plausible explanation to gender-dependent differences in correlations between the content of selected elements in rainwater and the frequency of hospitalization by reason of arterial hypertension, chronic obstructive pulmonary disease (COPD), and psoriasis in the area of Opolskie Voivodeship, Poland, during the period 2000-2002. The elements analyzed were sodium, potassium, calcium, magnesium, manganese, iron, total phosphorus, total nitrogen, ammonium nitrogen, zinc, copper, lead, cadmium, nickel, chromium, chloride, nitrate, and sulfate. Hospitalization due to arterial hypertension was more frequent in women, whereas those for COPD and psoriasis were more frequent in men. In the case of women hospitalized for arterial hypertension, the correlations were low, except for zinc (r = 0.47) and for cadmium (r = 0.43). In men hospitalized for COPD, all of the correlation coefficients were higher than 0.4, except for phosphorus. The coefficients for nickel, ammonia nitrogen, and total nitrogen ranged from 0.5 to 0.6 and the remaining elements from 0.6 to 0.7. In women, the correlation was limited to five elements where the coefficient was r > 0.4 for chloride, calcium, nitrate, phosphorus, and chromium. In cases of hospitalization for psoriasis, the correlation in men was between 0.4 and 0.5 for chloride, phosphorus, copper, lead, and total nitrogen and greater than 5 for sulfate, potassium, calcium, iron, manganese, nitrate, and ammonium nitrogen. The correlation in women was between 0.48 and 0.5 for ammonium nitrogen and phosphorus.  相似文献   

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