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1.
BACKGROUND: A national survey found that micronutrient deficiencies are prevalent in South African children, particularly calcium, iron, zinc, riboflavin, niacin, vitamin B6, folate, vitamin A, E and C. Mandatory fortification of maize meal and wheat flour were introduced in 2003 to combat some of the deficiencies found in children. To date however, there has not been a national survey on dietary intake in adults. OBJECTIVES: The main objectives of this study were to evaluate the micronutrient intake of the diet consumed by the average adult South African by means of secondary data analyses and secondly to evaluate the effects of fortification on selected nutrient intakes. STUDY DESIGN: Secondary data analysis was carried out with numerous dietary surveys on adults to create a database that included sampling (and weighting) according to ethnic/urban-rural residence in line with the population census, of which 79% were black Africans and the majority resided in rural areas. The effect of fortification was evaluated by substituting fortified foods in the diet for the unfortified products. SUBJECTS: The combined database used in this study comprised 3229 adults. RESULTS: Mean calcium, iron, folate and vitamin B6 intakes were very low particularly in women. Mean intakes of most micronutrients were lower in rural areas. Fortification of maize meal and wheat flour (bread) raised mean levels of thiamine, riboflavin, niacin, vitamin B6 and folate above the recommended nutrient intakes (RNIs). In women, despite fortification, mean iron intakes remained below the RNIs, as did calcium since it was not in the fortification mix. CONCLUSION: The average dietary intake of adults was of poor nutrient density, particularly in rural areas. Fortification of maize meal and wheat flour (bread) considerably improved mean vitamin B6, thiamine, riboflavin, niacin, folate and iron intakes as well as the overall mean adequacy ratio of the diet.  相似文献   

2.
OBJECTIVE: To assess changes in the Fe and vitamin A status of the population of Nangweshi refugee camp associated with the introduction of maize meal fortification. DESIGN: Pre- and post-intervention study using a longitudinal cohort. SETTING: Nangweshi refugee camp, Zambia. SUBJECTS: Two hundred and twelve adolescents (10-19 years), 157 children (6-59 months) and 118 women (20-49 years) were selected at random by household survey in July 2003 and followed up after 12 months. RESULTS: Maize grain was milled and fortified in two custom-designed mills installed at a central location in the camp and a daily ration of 400 g per person was distributed twice monthly to households as part of the routine food aid ration. During the intervention period mean Hb increased in children (0.87 g/dl; P < 0.001) and adolescents (0.24 g/dl; P = 0.043) but did not increase in women. Anaemia decreased in children by 23.4% (P < 0.001) but there was no significant change in adolescents or women. Serum transferrin receptor (log10-transformed) decreased by -0.082 microg/ml (P = 0.036) indicating an improvement in the Fe status of adolescents but there was no significant decrease in the prevalence of deficiency (-8.5%; P = 0.079). In adolescents, serum retinol increased by 0.16 micromol/l (P < 0.001) and vitamin A deficiency decreased by 26.1% (P < 0.001). CONCLUSIONS: The introduction of fortified maize meal led to a decrease in anaemia in children and a decrease in vitamin A deficiency in adolescents. Centralised, camp-level milling and fortification of maize meal is a feasible and pertinent intervention in food aid operations.  相似文献   

3.
Iron deficiency is the most common nutritional disorder worldwide. Iron fortification of foods is considered to be the most cost-effective long-term approach to reduce iron deficiency. However, for fortified foods to be effective in reducing iron deficiency, the added iron must be sufficiently bioavailable. In this study, fortification of whole-grain wheat flour with different sources of iron was evaluated in vitro by measuring the amount of dialyzable iron after simulated gastrointestinal digestion of flour baked into chapatis and subsequent intestinal absorption of the released iron using Caco-2 cell layers. The dialyzability of iron from iron-fortified wheat flour was extremely low. Additions of 50 mg/kg iron to the flour in the form of ferrous sulfate, Ferrochel amino acid chelate, ferric amino acid chelate taste free (TF), Lipofer, ferrous lactate, ferrous fumarate, ferric pyrophosphate, carbonyl iron, or electrolytic iron did not significantly increase the amount of in vitro dialyzable iron after simulated gastrointestinal digestion. In contrast, fortification of flour with SunActive Fe or NaFeEDTA resulted in a significant increase in the amount of in vitro dialyzable iron. Relative to iron from ferrous sulfate, iron from SunActive Fe and NaFeEDTA appeared to be 2 and 7 times more available in the in vitro assay, respectively. Caco-2 cell iron absorption from digested chapatis fortified with NaFeEDTA, but not from those fortified with SunActive Fe, was significantly higher than from digested chapatis fortified with ferrous sulfate. On the basis of these results it appears that fortification with NaFeEDTA may result in whole-grain wheat flour that effectively improves the iron status.  相似文献   

4.
Zinc‐inefficient Sanilac and Zn‐efficient Saginaw navy bean (Phaseolus vulgaris L.) differ in their susceptibility to Zn‐deficiency stress. Sanilac accumulates Fe under Zn‐deficiency stress and Saginaw does not. These two navy bean cultivars were grown at 0, 0.006 and 0.12 mg/L Zn in modified Hoagland nutrient solution. Various Fe‐stress response mechanisms were quantified periodically over a 12‐day experimental period to determine if known factors in the Fe‐stress response mechanism were enhanced by Zn‐deficiency stress. Visual Zn‐deficiency symptoms were more severe in Sanilac than Saginaw navy bean under equivalent Zn treatments. Sanilac contained lower leaf Zn than Saginaw when Zn was present in solution (0.006 and 0.12 mg/L Zn), but the two cultivars were similar in leaf Zn in the absence of Zn (0 mg/L Zn). Sanilac accumulated more leaf Fe than Saginaw when under Zn stress (0 and 0.006 mg/L Zn). The higher levels of leaf Fe in Sanilac than Saginaw were closely associated with enhanced release of reductants and increased reduction of Fe3+ to Fe2+ by roots of Sanilac. Saginaw navy bean roots reduced Fe3+ to Fe2+ similarly to Sanilac with adequate Zn present in solution (0.12 mg/L), but experienced minuscule levels of Fe3+ reduction under Zn deficiency. Zinc deficiency stimulated the initiation of the Fe‐stress response mechanism in Sanilac, but not Saginaw, which may have enhanced the development of Zn‐deficiency symptoms in Sanilac due to the increased uptake of Fe by this cultivar. The common Fe‐deficiency stress response associated primarily with grasses (release of phytosiderophore) was not found in either navy bean cultivar.  相似文献   

5.
Plant nutrient deficiencies are the main yield‐limiting factors in highly weathered acid soils around the world. Five greenhouse experiments were conducted on an Oxisol to identify nutrient deficiencies in common bean, upland rice, corn, wheat, and soybean. The treatments consisted of 13 fertility levels including an adequate level and remaining without application of one of the essential plant macro‐ or micronutrients. Dry matter yield of tops of all the crop species was affected by fertility treatments; however, significant effects of treatments were obtained in the case of common bean, upland rice, and corn. Based on tops dry weight under different treatments compared to adequate fertility level (AFL), the most yield‐limiting nutrients were in the order of phosphorus (P) > calcium (Ca) > magnesium (Mg) > boron (B) > zinc (Zn) for common bean, P > molybdenum (Mo) for upland rice, and P for corn. For the wheat crop, there was substantial decrease in tops dry weight in the absence of Ca, P, and potassium (K) nutrients. In the case of soybean, substantial tops dry weight reduction was due to deficiency in the order of P >Ca>Zn.  相似文献   

6.
OBJECTIVE: To examine the prevalence and risk factors of vitamin deficiencies among older Thai adults. METHODS: The cross-sectional study was conducted in four rural communities, one from each of the four main regions of Thailand. In total, 2336 subjects aged 60 years and over were recruited. Anthropometric variables, demographic data, blood glucose and lipid profile, albumin, globulin and blood levels of vitamin A, beta-carotene, folic acid, vitamin B12, vitamin C, vitamin E and vitamin B1 were all measured. RESULTS: The prevalence of vitamin deficiencies was 0.6% for vitamin B12, 6.1% for vitamin A, 9.9% for vitamin C, 30.1% for vitamin B1, 38.8% for erythrocyte folate, 55.5% for vitamin E and 83.0% for beta-carotene. Male gender was a common risk factor for at least three vitamin deficiencies, i.e. beta-carotene, folate and vitamin E. Being a manual worker was a common risk factor of beta-carotene and vitamin B1 deficiency. Poor income was found as a risk factor only in erythrocyte folate deficiency while increasing age was a significant factor only in vitamin C deficiency. CONCLUSION: The prevalence of vitamin deficiencies among older Thai people was quite different from that found in Western countries, reflecting different socio-economic backgrounds. Vitamin deficiency was not only from poor food intake but also from the dietary habit of monotonous food consumption in older people. Some common associated factors of atherosclerosis were also significantly related to folate and vitamin E deficiencies.  相似文献   

7.
Iron deficiency stress causes a severe reduction in plant growth. Although Fe deficiency causes an imbalance in divalent heavy metal nutrients, the mechanisms underlying the growth reduction caused by this imbalance remain unclear. We investigated Zn uptake and accumulation in maize under Fe-deficient conditions. Under Fe-deficient conditions, Zn uptake was 15-fold higher and Zn accumulation was 16-fold higher than that under normal nutrient conditions. The Zn content of maize leaves under Fe-deficient conditions was >0.4 mg g−1 dry weight, which was higher than the content of plants grown in a nutrient solution containing 50 µM ZnCl2. Plant growth under conditions of both Fe and Zn deficiency was significantly higher than that under only Fe-deficient conditions. Moreover, Fe deficiency increased the thiol content of the plant. These results indicate that Fe deficiency causes excess uptake and accumulation of Zn, and that the stress resulting from the Zn overload accelerates growth reduction in maize.  相似文献   

8.
OBJECTIVE: To evaluate the effectiveness of a vitamin-fortified maize meal to improve the nutritional status of 1-3-year-old malnourished African children. DESIGN: A randomised parallel intervention study was used in which 21 experimental children and their families received maize meal fortified with vitamin A, thiamine, riboflavin and pyridoxine, while 23 control children and their families received unfortified maize meal. The maize meal was provided for 12 months to replace the maize meal habitually consumed by these households. METHODS: Sixty undernourished African children with height-for-age or weight-for-age below the 5th percentile of the National Center for Health Statistics' criteria and aged 1-3 years were randomly assigned to an experimental or control group. Baseline measurements included demographic, socio-economic and dietary data, as well as height, weight, haemoglobin, haematocrit, serum retinol and retinol-binding protein (RBP). Anthropometric, blood and serum variables were measured again after 12 months of intervention. Complete baseline measurements were available for 44 children and end data for only 36. Changes in these variables from baseline to end within and between groups were assessed for significance with paired t-tests, t-tests and analysis of variances using the SPSS program, controlling for expected weight gain in this age group over 12 months. Relationships between changes in variables were examined by calculating correlation coefficients. RESULTS: The children in the experimental group had a significantly (P < or = 0.05) higher increase in body weight than control children (4.6 kg vs. 2.0 kg) and both groups had significant (P < or = 0.05) but similar increases in height. The children in the experimental group showed non-significant increases in haemoglobin and serum retinol, while the control children had a significant (P = 0.007) decrease in RBP. The change in serum retinol showed a significant correlation with baseline retinol (P = 0.014), RBP (P = 0.007) and weight (P = 0.029), as well as with changes in haemoglobin (P = 0.029). CONCLUSION: Despite a small sample size, this study showed positive effects of a vitamin-fortified maize meal on weight gain and some variables of vitamin A status in 1-3-year-old African children. The study confirmed the relationship between vitamin A and iron status. The results suggest that fortification of maize meal would be an effective strategy to address micronutrient deficiencies in small children in South Africa.  相似文献   

9.
Considering the widespread insufficiency of vitamin D, the fortification of additional foods with vitamin D is warranted. The objective of this research was to assess the feasibility of vitamin D3 fortification in natural hard cheeses. We examined the recovery, distribution, long-term retention, and heat stability of the vitamin in industrially made fortified Cheddar and low-fat cheeses. The results indicated that the vitamin D3 did not degrade during processing, over 1 year of ripening (3-8 degrees C), or after thermal treatment at 232 degrees C for 5 min. Vitamin D3 recovery in the fortified Cheddar and low-fat cheeses were, respectively, 91 and 55% of the vitamin D3 added to the milk used to make each cheese. The remaining vitamin D3 was entrained in the whey. The vitamin D3 was uniformly distributed throughout the blocks of cheese. The fortification process did not alter the yield, chemical composition, or flavor of the Cheddar cheese. We conclude that industrially manufactured Cheddar and low-fat cheeses are suitable for vitamin D3 fortification.  相似文献   

10.
Rice is the staple food for more than half of the world's population and, hence, the main source of a vital micronutrient, zinc (Zn). Unfortunately, the bioavailability of Zn from rice is very low not only due to low content but also due to the presence of some antinutrients such as phytic acid. We investigated the effect of germination and Zn fortification treatment on Zn bioavailability of brown rice from three widely grown cultivars using the Caco-2 cell model to find a suitable fortification level for producing germinated brown rice. The results of this study showed that Zn content in brown rice increased significantly (p < 0.05) as the external Zn concentrations increased from 25 to 250 mg/L. In contrast, no significant influence (p > 0.05) on germination percentage of rice was observed when the Zn supply was lower than 150 mg/L. Zn fortification during the germination process has a significant impact on the Zn content and finally Zn bioavailability. These findings may result from the lower molar ratio of phytic acid to Zn and higher Zn content in Zn fortified germinated brown rice, leading to more bioavailable Zn. Likewise, a significant difference (p < 0.05) was found among cultivars with respect to the capacity for Zn accumulation and Zn bioavailability; these results might be attributed to the difference in the molar ratio of phytic acid to Zn and the concentration of Zn among the cultivars evaluated. Based on global intake of Zn among the world population, we recommend germinated brown rice fortified with 100 mg/L ZnSO(4) as a suitable concentration to use in the germination process, which contains high Zn concentration and Zn bioavailability. In the current study, the cultivar Bing91185 fortified with Zn through the germination process contained a high amount as well as bioavailable Zn, which was identified as the most promising cultivar for further evaluation to determine its efficiency as an improved source of Zn for target populations.  相似文献   

11.
Micronutrient deficiencies have been reported in food crops worldwide. Several macro- and micronutrients are essential for human health. However, among these elements, the trace elements zinc (Zn), iron (Fe), iodine (I), selenium (Se), and cobalt (Co) are limiting in the diets of much of the world's population. According to United Nations estimates, about 1 billion people, especially woman and children, are suffering from malnutrition of trace elements, especially in Africa, Asia, and South America. Improving bioavailability of these elements in food crops is an important strategy to overcome trace-element deficiencies in food crops and improving human health. Genetic variability in micronutrient contents in the grain of crops such as rice, corn, wheat, barley, soybean, and dry bean is widely reported in the literature. Hence, use of genetic variability among crop species and genotypes within species is an important strategy to achieve biofortification of grain of staple food crops. Other practices that can be adopted to improve bioavailability of essential elements in food crops are adopting appropriate agronomic practices, such as adequate rate, effective sources, and effective methods of fertilizer application. Use of biotechnology is also feasible to biofortification of staple food crops. Planting indigenous and traditional food crop species with high nutritive value is another important strategy to improve trace elements in human food.  相似文献   

12.
In many parts of the world, soils deficient and/or toxic in micronutrients reduce potential soybean (Glycine max) yields. The objective of our study was to grow plants in low to high concentrations of boron (B) and zinc (Zn) to determine how B and Zn deficiencies and toxicities affect soybean growth and interact with other essential nutrients in roots, leaves, and seeds. We found that B significantly affected levels of all essential nutrients except manganese and iron, while Zn significantly affected all essential nutrients in at least one plant tissue tested. Some of the physiological responses and nutrient interactions were cultivar-dependent. This study showed how deficiencies and toxicities of B and Zn affect plant growth and how B and Zn fertility interacts with many of the other essential nutrients.  相似文献   

13.
ABSTRACT

Indian mustard (Brassica juncea Czern) is a promising species for the phytoextraction of zinc (Zn), but the effectiveness of this plant can be limited by iron (Fe) deficiency under Zn-contaminated conditions. Our objectives were to determine the effects of root-applied Fe and Zn on plant growth, accumulation of Zn in plant tissues, and development of nutrient deficiencies for B. juncea. In the experiment, B. juncea was supplied 6 levels of iron ethylenediamine dihydroxyphenylacetic acid (Fe-EDDHA; 0.625 to 10.0 mg L?1) and two levels of Zn (2.0 and 4.0 mg L?1) for 3 weeks in a solution-culture experiment. Nutrient solution pH decreased with decreasing supply of Fe and increasing supply of Zn in solution, indicating that B. juncea may be an Fe-efficient plant. If plants were supplied 2.0 mg Zn L?1, plant growth was stimulated by increases in Fe supply, but plant growth was not influenced by Fe treatments if plants were supplied 4.0 mg Zn L?1. Zinc concentration in roots and shoots was suppressed by increasing levels of Fe in solution. Leaf concentrations of Cu, Mn, and P were suppressed also as Fe supply in solutions increased. Iron additions to the nutrient solution were not effective at increasing the Zn-accumulation potential of B. juncea unless plants were supplied the higher level of Zn in solution culture. Even under these conditions, Fe additions were effective only if supplied at low levels in solution culture (1.25 mg Fe L?1). Results suggest that Fe fertility has limited potential for enhancing Zn phytoextraction by B. juncea, even if plants suffer a suppression in growth from Fe deficiency.  相似文献   

14.
缺铁是个世界性的营养失衡问题,给人类健康和经济发展带来严重的负面影响。主要膳食中的铁缺乏或低生物有效性被认为是造成铁缺乏的主要原因。通过植物育种措施,尤其是提高植物源铁富集育种被认为是解决铁营养失衡最经济且有效的途径。然而,近年的研究表明,人体铁吸收与植物源有效铁量密切相关,而与铁积累总量没有相关性。快速、准确的评价植物源铁生物有效性对高有效性富铁作物育种意义重大。本文阐述了植物源铁富集和生物有效性的基因型差异及影响因素, 并分析了铁生物有效性评价方法的优缺点,为植物源铁生物有效性育种及评价提供参考。  相似文献   

15.
Daily intake levels of vitamin E in the range of 200–800 IU are now recommended for its antioxidant effect. However, only vitamin E supplements or fortified foods may provide these high intake levels. As a fortified food, breads were prepared containing 200, 400, 800, or 1,600 IU of added vitamin E (dl‐α‐tocopheryl acetate) per pound loaf. These levels of fortification exerted no adverse effects on bread quality. However, only about two‐thirds of the added vitamin E was retained (recovered) in the breads, with retention values showing no further significant change during the seven‐day shelf‐life of the product. In fresh breads, vitamin E retention values were nearly the same (range 66.3–68.5%, average 67.2%) at all levels of vitamin E tested; this may hold true for levels not tested. Factoring in an average retention value of 67.2%, and actual potency (81.8%) of the vitamin E source used, a 50‐g serving of bread fortified with 1,600 IU of vitamin E per loaf would provide nearly one‐fourth of a suggested daily intake of 400 IU.  相似文献   

16.
In order to prioritise interventions for micronutrient deficiencies in China, the populations affected by iron and zinc deficiencies were assessed based on data from the 2002 China National Nutrition and Health Survey. The costs and cost-effectiveness of supplementation, food diversification and food fortification were estimated using the standard World Health Organization ingredients approach. Results indicated that 30% of children (60 years), pregnant and lactating women, and 20% of women of reproductive age were anaemic, some 245 million people. Approximately 100 million people were affected by zinc deficiency (zinc intake inadequacy and stunting), the majority living in rural areas. Among interventions on iron and zinc deficiency, biofortification showed the lowest costs per capita, I 0.01 (international dollars), while dietary diversification through health education represented the highest costs at I 1148(international dollars). The cost-effectiveness of supplementation, food fortification and dietary diversification for iron deficiency alone was I 179(international dollars) , I 66 and I 103 (international dollars) per disability-adjusted life-year (DALY), respectively. Data for biofortification were not available. For zinc deficiency, the corresponding figures were I 399(international dollars), I 153(international dollars) and I 103(international dollars) per DALY, respectively. In conclusion, iron and zinc deficiencies are of great public health concern in China. Of the two long-term intervention strategies, i.e. dietary diversification and biofortification with improved varieties, the latter is especially feasible and cost-effective for rural populations. Supplementation and fortification can be used as short-term strategies for specific groups.  相似文献   

17.
In arecanut, disorders like crown choking and crown bending lead to death of palms within a short span. Spatial and temporal variability in soil and leaf nutrient status was used as a tool to find out the causes for disorders in clay and laterite soils. Availability of nutrients in soils was sufficient to excess. Deviation from optimum percentage index was negative for nitrogen (N), phosphorus (P), and zinc (Zn) in both soils. Zinc deficits of –26 to –63 in higher number of palms (84–97%) indicate the reduction in Zn uptake. Regression between leaf Zn and soil fertility parameters indicated negative relation with soil Zn and calcium (Ca) in clay and soil organic carbon, soil P, and soil boron (B) in laterite soils. Multiple regression indicated negative relation of diethylenetriaminepentaacetic acid (DTPA)-extractable Zn with nutrients like Ca, magnesium (Mg), potassium (K), and iron (Fe) in soil in different years. The grouping of soil nutrients in opposite directions in first two components of principal component analysis supports negative nutrient interactions in both soil types. The results reveal that nutrient interactions in soil affect the uptake of nutrients despite sufficient nutrient availability. Zinc deficiency in arecanut may be the result of complex interactions between DTPA-extractable Zn and other nutrients in soil.  相似文献   

18.
The effect of natural and controlled fermentation with an inoculum of Lactobacillus plantarum and additional thermal treatment (dry heat at 120 degrees C for 20 min) on the availability of N, P, Fe, Cu, Zn, Ca, and Mg from Phaseolus vulgaris L. var. carrilla was estimated using an in vitro method based on equilibrium dialysis. Natural and controlled fermentations caused significant reductions in the pH and phytate content (36%) of the bean flours, with a concomitant increase in the titratable acidity and free phosphorus content, and had no effect on the other nutrients studied. The percentage of dialyzable N, P, Cu, and Mg was significantly improved by both types of fermentation, whereas Zn dialyzability was significantly reduced. The greatest reduction was observed for the bean flour fermented with an inoculum of L. plantarum. The percentage of dialyzable Fe improved significantly as a result of natural fermentation but was not affected by controlled fermentation. The application of dry heat at 120 degrees C for 20 min caused a significant increase in Fe dialyzability and a further reduction in the percentage of dialyzable Zn in fermented bean flours but did not affect the dialyzability of the other nutrients studied.  相似文献   

19.
This research was conducted to determine the effectiveness of various treatments in correction of single deficiency of iron (Fe) and multiple deficiencies of Fe, zinc (Zn), and boron (B) in an olive cultivar (Gemlik) in the southeastern Marmara region of Turkey. This study was consisted of four field experiments, which included control, soil and foliar applications of Fe alone, and combinations with Zn and B. Soil applications of the compounds were only performed in the first year of the experiments to estimate residual effect of soil applications in the following year. Foliar applications were sprayed onto leaves two and four times at two doses in consecutive years. Soil application of iron sulfate did not increase Fe concentrations in the both leaves and fruits. Foliar applications of iron sulfate considerably elevated leaf total and active Fe concentrations, but the effect of the foliar applications on fruit Fe concentrations was small. Two foliar applications of iron in each season seemed to be appropriate treatment in the all experiments, as well. To maintain sufficient Fe concentrations, especially in the newly developing tissues of olive trees, foliar application of Fe should be conducted at least four times at the lowest dose as performed in the experiments. Foliar applications of double and triple combinations of iron sulfate with zinc sulfate and borax increased significantly B and Zn concentrations in the trees, as well.  相似文献   

20.
Low and unstable fruit yield, poor quality of fruits, and excessive fruit dropping are major problems in a lime crop and are due to either micronutrient deficiencies or nutrient imbalance. A study was conducted to assess the micronutrient status in a lime orchard at the Central Soil and Water Conservation Research and Training Institute (CSWCRTI)’s research farm in Kota, Rajasthan, India. Plant and soil samples were collected during September and October in 2006–2007. The micronutrients extracted with diethylenetriaminepentaacetic acid (DTPA) in soils were in the order of manganese (Mn) > iron (Fe) > zinc (Zn) > copper (Cu). The mean values of DTPA Mn, Fe, Zn, and Cu in surface soils varied from 13.98 to 22.70, 2.48 to 8.66, 0.79 to 1.19, and 0.14 to 0.46 mg kg?1, respectively, whereas in subsurface soils they varied from 12.94 to 23.06, 4.84 to 6.52, 0.51 to 0.83, and 0.07 to 0.20 mg kg?1, respectively. Results reveal that except for Fe, the other DTPA-extractable micronutrients decreased with depth. Total Mn, Fe, Zn, and Cu in plant leaves varied from 22 to 83, 70 to 630, 40 to 932, and 37 to 3057 mg kg?1, respectively, indicating greater or toxic concentrations of total micronutrient in leaf samples. Total Mn, Fe, Zn, and Cu in petiole samples varied from 7 to 60, 235 to 574, 70 to 827, and 101 to 2623 mg kg?1, respectively. High concentration of Cu and Zn in leaves resulted in Fe and Mn deficiencies (exhibited as leaf chlorosis) in lime plants. Results of the study indicated that Fe and Mn deficiencies are major disorders in lime plantation. Similarly, the measure of DTPA-extractable micronutrients showed the low statuses of Fe and Cu and marginal status of Zn in soils along the Chambal region.  相似文献   

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