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1.
Nicholas G. Paltridge Lachlan J. Palmer Paul J. Milham Georgia E. Guild James C. R. Stangoulis 《Plant and Soil》2012,361(1-2):251-260
Background and aims
Rice (Oryza sativa L.) and pearl millet (Pennisetum glaucum L.) biofortification breeding programs require accurate and convenient methods to identify nutrient dense genotypes. The aim of this study was to investigate energy-dispersive X-ray fluorescence spectrometry (EDXRF) for the measurement of zinc (Zn) and iron (Fe) concentration in whole grain rice and pearl millet.Methods
Grain samples were obtained from existing biofortification breeding programs. Reference Zn and Fe concentrations obtained by inductively-coupled plasma-optical emission spectroscopy (ICP-OES) were used to calibrate the EDXRF instrument. Calibration was performed with 24 samples and separate calibrations were developed for rice and pearl millet. To validate calibrations, EDXRF analyses were conducted on an additional 40 samples of each species.Results
EDXRF results were highly correlated with ICP-OES values for both Zn and Fe in both species (r2?=?0.79 to 0.98). EDXRF predicted Zn and Fe in rice to within 1.9 and 1.6?mg?kg?1 of ICP-OES values, and Zn and Fe in pearl millet to within 7.6 and 12.5?mg?kg?1 of ICP-OES values, at a 95% confidence level.Conclusion
EDXRF offers a convenient, economical tool for screening Zn and Fe concentration in rice and pearl millet biofortification breeding programs. 相似文献2.
Amir Hossein Khoshgoftarmanesh Hamid Zeinali Behzadan Azadeh SanaeiOstovar Rufus L. Chaney 《Plant and Soil》2012,361(1-2):71-81
Background and Aims
We tested the utility of some biological treatments to hasten degradation of waste tire rubber in soil and thus the release of zinc and sulfur for plant uptake.Methods
Three rates of ground tire rubber (0, 150, and 300?mg?kg?1) were incorporated into a Zn-deficient calcareous soil. Before addition to the soil, ground rubber was given four microbial treatments including no inoculation, inoculation with Rhodococcus erythropolis, inoculation with R. erythropolis+Escherichia coli, and inoculation with R. erythropolis+E. coli+Acinobacter calcoaceticus. In the pot experiment, corn (Zea mays L. Hybrid Single Cross 500) and sunflower (Helianthus annuus L. cv. Record) plants were exposed to three rates of ground rubber (0, 150, and 300?mg?kg?1) or 3?mg zinc kg?1 as ZnSO4. Before addition to the soil, ground rubber and ZnSO4 were inoculated or non-inoculated with R. erythropolis+E. coli+A. calcoaceticus.Results
Ground rubber and microbial inoculation treatments reduced soil pH and the magnitude of this reduction increased over time. Ground rubber in combination with microbial inoculation increased DTPA-extractable soil Zn and Fe. The amount of DTPA-extractable Zn and Fe of rubber-amended soils increased over time so that the highest concentration of available Zn and Fe was found at week 10. Application of microbial inoculated ground tire rubber significantly increased shoot Zn concentration of each plant species.Conclusions
Bacterial inoculation of ground rubber was effective in hastening increase in DTPA-extractable Zn in the studied calcareous soil and in enhancing Zn uptake by plants. 相似文献3.
Selenium accumulation in durum wheat and spring canola as a function of amending soils with selenite, selenate and or sulphate 总被引:3,自引:0,他引:3
Aims
A comparison was performed between plant species to determine if extractable, rather than total soil Se, is more effective at predicting plant Se accumulation over a full growing season.Methods
Durum wheat (Triticum turgidum L.) and spring canola (Brassica napus L.) were sown in potted soil amended with 0, 0.1, 1.0, or 5.0 mg kg?1 Se as SeO4 2? or SeO3 2?. In addition, SeO4 2?-amended soils were amended with 0 or 50 mg kg?1 S as SO4 2?. Soils were analyzed for extractable and total concentration of Se ([Se]). Twice during the growing season plants were harvested and tissue [Se] was determined.Results
Plants exposed to SeO3 2? accumulated the least Se. Fitted predictive models for whole plant accumulation based on extractable soil [Se] were similar to models based on total [Se] in soil (R2?=?0.73 or 0.74, respectively) and selenium speciation and soil [S] were important soil parameters to consider. As well, soil S amendments limited Se toxicity.Conclusions
Soil quality guidelines (SQGs) based on extractable Se should be considered for risk assessment, particularly when Se speciation is unknown. Predictive models to estimate plant Se uptake should include soil S, a modifier of Se accumulation. 相似文献4.
Does radial oxygen loss and iron plaque formation on roots alter Cd and Pb uptake and distribution in rice plant tissues? 总被引:5,自引:0,他引:5
Background and Aims
Metal (e.g. Cd and Pb) pollution in agricultural soils and crops have aroused considerable attention in recent years. This study aimed to evaluate the effects of ROL and Fe plaque on Cd and Pb accumulation and distribution in the rice plant.Methods
A rhizobag experiment was employed to investigate the correlations among radial oxygen loss (ROL), Fe plaque formation and uptake and distribution of Cd and Pb in 25 rice cultivars.Results
Large differences between the cultivars were found in rates of ROL (1.55 to 6.88 mmol O2 kg?1 root d.w. h?1), Fe plaque formation (Fe: 6,117–48,167 mg kg?1; Mn: 127–1,089 mg kg?1), heavy metals in shoot (Cd: 0.13–0.35 mg kg?1; Pb: 4.8–8.1 mg kg?1) and root tissues (Cd: 1.1–3.5 mg kg?1; Pb: 45–199 mg kg?1), and in Fe plaque (Cd: 0.54–2.6 mg kg?1; Pb: 102–708 mg kg?1). Rates of ROL were positively correlated with Fe plaque formation and metal deposition on root surfaces, but negatively correlated with metal transfer factors of root/plaque and distributions in shoot and root tissues.Conclusions
ROL-induced Fe plaque promotes metal deposition on to root surfaces, leading to a limitation of Cd and Pb transfer and distribution in rice plant tissues. 相似文献5.
Background and aims
A critical soil mineral nitrogen concentration (Nmin) for guiding fertilizer application and maximizing maize grain yield is needed.Methods
A three-year field experiment with three N regimes, unfertilized (N0), optimized N management (Opt.) and conventional N practice (Con.) was performed in maize.Results
The mean soil Nmin in 0–60 cm soil profile for N0, Opt. and Con. treatments was 2.0, 6.7 and 8.9 mg?kg–1 at V8–VT growth stages and 2.2, 6.1 and 11.2 mg?kg–1 on average over the whole growth season, respectively. Correspondingly, the soil N supplying capacity (soil Nmin content?+?fertilizer N) of the three N treatments was smaller, identical or greater than the plant N accumulation at different growth stages. The Opt. treatment had significantly higher N use efficiency, N recovery efficiency and N partial factor productivity compared with the Con. treatment, while it did not cause maize yield loss.Conclusions
Compared with the insensitivity of the critical shoot N dilution curve to excessive N application, soil Nmin showed strong response to all treatments. We propose a minimum of soil Nmin of 6.1 mg?kg–1 at the sowing–V8, 6.7 mg?kg–1 at the V8–VT, and 5.5 mg?kg–1 at the VT–R6 growing stages with an average of about 6 mg?kg–1 of soil Nmin in the 0–60 soil depth for maximizing maize yield and N use efficiency in northern China. To maintain this critical Nmin value over the whole growth period, N topdressing at V8 and V12 stages was recommended. 相似文献6.
Yong Liang Yuexing Chen Dong Liu Jianping Cheng Gang Zhao Tzion Fahima Jun Yan 《Phyton》2020,89(2):423-435
Mineral nutrient malnutrition, especially deficiency in selenium (Se),
affects the health of approximately 1 billion people worldwide. Wheat, a staple
food crop, plays an important role in producing Se-enriched foodstuffs to increase
the Se intake of humans. This study aimed to evaluate the effects of different Se
application methods on grain yield and nutritional quality, grain Se absorption and
accumulation, as well as 14 other trace elements concentrations in wheat grains.
A sand culture experiment was conducted via a completely randomized 3 × 2 × 1
factorial scheme (three Se levels × two methods of Se application, foliar or soil ×
one Se sources, selenite), with two wheat cultivars (Guizi No.1, Chinese Spring).
The results showed that both foliar Se and soil Se application methods had effects
on wheat pollination. Foliar Se application resulted in early flowering of wheat,
while soil Se application caused early flowering of wheat at low Se levels
(5 mg kg−1
) and delayed wheat flowering at high selenium levels (10 mg kg−1
),
respectively. For trace elements, human essential trace elements (Fe, Zn, Mn, Cu,
Cr, Mo, Co and Ni) concentrations in wheat grains were dependent of Se application methods and wheat cultivars. However, toxic trace elements (Cd, Pb, Hg, As,
Li and Al) concentrations can be decreased by both methods, indicating a possible
antagonistic effect. Moreover, both methods increased Se concentrations, and
improved grain yield and nutritional quality, while the foliar application was better than soil. Accordingly, this study provided useful information concerning
nutritional biofortification of wheat, indicating that it is feasible to apply Se to
conduct Se biofortification, inhibit the heavy metal elements concentrations and
improve yield and quality in crops, which caused human health benefits. 相似文献
7.
Zinc fertilizer placement affects zinc content in maize plant 总被引:1,自引:0,他引:1
Yue-Qiang Zhang Li-Li Pang Peng Yan Dun-Yi Liu Wei Zhang Russell Yost Fu-Suo Zhang Chun-Qin Zou 《Plant and Soil》2013,372(1-2):81-92
Background and aims
Adequate zinc (Zn) in maize (Zea mays L.) is required for obtaining Zn-enriched grain and optimum yield. This study investigated the impact of varying Zn fertilizer placements on Zn accumulation in maize plant.Methods
Two pot experiments with same design were conducted to investigate the effect of soil Zn heterogeneity by mixing ZnSO4·7H2O (10 mg Zn kg?1 soil on an average) in 10–15, 0–15, 25–30, 0–30, 30–60 and 0–60 cm soil layers on maize root growth and shoot Zn content at flowering stage in experiment-1, and assessing effects on grain Zn accumulation at mature stage in experiment-2.Results
In experiment-1, Zn placements created a large variation in soil DTPA-Zn concentration (0.3–29.0 mg kg?1), which induced a systemic and positive response of root growth within soil layers of 0–30 cm; and shoot Zn content was increased by 102 %–305 % depending on Zn placements. Supply capacity of Zn in soil, defined as sum of product of soil DTPA-Zn concentration and root surface area at different soil layers, was most related to shoot Zn content (r?=?0.82, P?<?0.001) via direct and indirect effects according to path analysis. In experiment-2, Zn placements increased grain Zn concentration by up to 51 %, but significantly reduced the grain Zn harvest index from 50 % by control to about 30 % in average.Conclusion
Matching the distribution of soil applied Zn with root by Zn placement was helpful to maximize shoot Zn content and grain Zn concentration in maize. 相似文献8.
Eleftheria Stavridou Scott D. Young Kristian Thorup-Kristensen 《Plant and Soil》2012,351(1-2):149-160
Background and Aims
Selenium (Se) is an essential nutrient for humans and animals. In order to ensure an optimal concentration of Se in crops, Se fertilisers are applied. Catch crops may be an alternative way to increase Se concentrations in vegetables.Methods
Three experiments in Denmark between 2007–10 investigated the ability of catch crops (Italian ryegrass, fodder radish and hairy vetch) under different fertiliser regimes to reduce soil Se content in the autumn and to increase its availability in spring to the succeeding crop.Results and Conclusions
The catch crops (Italian ryegrass and fodder radish) increased water-extractable Se content in the 0.25–0.75?m soil layer in only one of the experiments. Selenium uptake by the catch crops varied between 65 and 3263?mg?ha?1, depending on species, year and fertilisation treatment; this corresponded to 0.1–3.0% of the water-extractable soil Se content. The influence of catch crops on Se concentrations and uptake in onions and cabbage was low. There was a decrease in Se uptake and recovery of applied Se by onions following catch crops, which might indicate Se immobilisation during catch crop decomposition. 相似文献9.
The reduction in zinc concentration of wheat grain upon increased phosphorus-fertilization and its mitigation by foliar zinc application 总被引:4,自引:0,他引:4
Yue-Qiang Zhang Yan Deng Ri-Yuan Chen Zhen-Ling Cui Xin-Ping Chen Russell Yost Fu-Suo Zhang Chun-Qin Zou 《Plant and Soil》2012,361(1-2):143-152
Background and aims
Malnutrition resulting from zinc (Zn) and iron (Fe) deficiency has become a global issue. Excessive phosphorus (P) application may aggravate this issue due to the interactions of P and micronutrients in soil crop. Crop grain micronutrients associated with P applications and the increase of grain Zn by Zn fertilization were field-evaluated.Methods
A field experiment with wheat was conducted to quantify the effect of P applications on grain micronutrient quality during two cropping seasons. The effect of foliar Zn applications on grain Zn quality with varied P applications was tested in 2011.Results
Phosphorus applications decreased grain Zn concentration by 17–56%, while grain levels of Fe, manganese (Mn) and copper (Cu) either remained the same or increased. Although P applications increased grain yield, they restricted the accumulation of shoot Zn, but enhanced the accumulation of shoot Fe, Cu and especially Mn. In 2011, foliar Zn application restored the grain Zn to levels occurring without P and Zn application, and consequently reduced the grain P/Zn molar ratio by 19–53% than that without Zn application.Conclusions
Foliar Zn application may be needed to achieve both favorable yield and grain Zn quality of wheat in production areas where soil P is building up. 相似文献10.
Soil properties and C dynamics in abandoned and cultivated farmlands in a semi-arid ecosystem 总被引:1,自引:0,他引:1
Fayez Raiesi 《Plant and Soil》2012,351(1-2):161-175
Background and Aims
Land abandonment might be an alternative management for restoring soil conditions and C from prolonged cultivation and agricultural practices. In the present study, the influence of 18–22?years of land abandonment on soil properties, C dynamics and microbial biomass was evaluated in closely situated wheat and alfalfa farmlands, and abandoned lands on calcareous soils, Central Iran.Methods
Soil properties of the 0–15 and 15–30?cm depths from abandoned lands were compared to those from conventionally cultivated lands (i.e., continuous wheat–fallow and alfalfa–wheat rotation) common in calcareous soils of Central Zagros Mountains.Results
Soil bulk density in the 0–15 and 15–30?cm layers decreased significantly while total porosity increased significantly in abandoned lands. Generally, soil aggregate stability tended to increase within the abandoned fields owing to increased water-stable macro-aggregates. Soil organic C (OC) contents (g kg?1) and pools (Mg ha?1) in the 0–15?cm soil layer increased significantly in abandoned lands compared with cultivated lands, with no effect in the 15–30?cm soil layer after 18–22?years of land abandonment, suggesting the restoration of C is pronounced in the upper 0–15?cm soil depth . The total C accumulation in abandoned lands was 7.0?Mg?C?ha?1 for the entire sampling depth (0–30?cm) over the 18–22?years of land abandonment, which was 26% greater relative to cultivated lands. Carbon mineralization (Cmin) followed a trend similar to organic C, whereas C turnover (Cmin/OC ratio) was slightly greater in wheat fields. However, soil microbial biomass C (MBC) did not vary considerably among the three land uses.Conclusions
In brief, improvements, albeit slowly, in soil properties of the top layer with the cessation of cultivation indicated that land abandonment may result in enhanced soil C sequestration, and would maintain fertility and productivity of the farmlands of semi-arid climates. 相似文献11.
Abdul Rehman Muhammad Farooq Levent Ozturk Muhammad Asif Kadambot H. M. Siddique 《Plant and Soil》2018,422(1-2):283-315
Background
Zinc (Zn) deficiency is one of the most important micronutrient disorders affecting human health. Wheat is the staple food for 35% of the world’s population and is inherently low in Zn, which increases the incidence of Zn deficiency in humans. Major wheat-based cropping systems viz. rice–wheat, cotton–wheat and maize–wheat are prone to Zn deficiency due to the high Zn demand of these crops.Methods
This review highlights the role of Zn in plant biology and its effect on wheat-based cropping systems. Agronomic, breeding and molecular approaches to improve Zn nutrition and biofortification of wheat grain are discussed.Results
Zinc is most often applied to crops through soil and foliar methods. The application of Zn through seed treatments has improved grain yield and grain Zn status in wheat. In cropping systems where legumes are cultivated in rotation with wheat, microorganisms can improve the available Zn pool in soil for the wheat crop. Breeding and molecular approaches have been used to develop wheat genotypes with high grain Zn density.Conclusions
Options for improving grain yield and grain Zn concentration in wheat include screening wheat genotypes for higher root Zn uptake and grain translocation efficiency, the inclusion of these Zn-efficient genotypes in breeding programs, and Zn fertilization through soil, foliar and seed treatments.12.
Changes in photosynthesis, antioxidant enzymes and lipid peroxidation in soybean seedlings exposed to UV-B radiation and/or Cd 总被引:1,自引:0,他引:1
Xuemei Li Lihong Zhang Yueying Li Lianju Ma Ning Bu Chunyan Ma 《Plant and Soil》2012,351(1-2):377-387
Aims
With a high growth rate and biomass production, bamboos are frequently used for industrial applications and recently have proven to be useful for wastewater treatment. Bamboos are considered as Si accumulators and there is increasing evidence that silicon may alleviate abiotic stresses such as metal toxicity. The aim of this study was to investigate the extent of metal concentrations and possible correlations with Si concentrations in plants.Methods
This study presents, for the first time, reference values for silicon (Si), copper (Cu) and zinc (Zn) concentrations in stems and leaves of various bamboo species grown under the natural pedo-climatic conditions of the island of Réunion (Indian Ocean).Results
A broad range of silicon concentrations, from 0 (inferior to detection limit) to 183 mg g?1 dry matter (DM), were found in stems and leaves. Mean leaf Cu and Zn concentrations were low, i.e. 5.1 mg kg?1 DM and 15.7 mg kg?1 DM, respectively. Silicon, Cu and Zn concentrations increased over the following gradient: stem base?<?stem tip?<?leaves. Significant differences in Si, Cu and Zn contents (except Zn in the stem) were noted between bamboo species, particularly between monopodial and sympodial bamboo species, which differ in their rhizome morphology. Sympodial bamboos accumulated more Si and Cu than monopodial bamboos, in both stems and leaves, whereas sympodial bamboos accumulated less Zn in leaves than monopodial bamboos.Conclusions
The findings of this study suggest that a genotypic character may be responsible for Si, Cu and Zn accumulation in bamboo. 相似文献13.
The effect of transpiration on selenium uptake and mobility in durum wheat and spring canola 总被引:6,自引:0,他引:6
Heidi Renkema Amy Koopmans Leanne Kersbergen Julie Kikkert Beverley Hale Edward Berkelaar 《Plant and Soil》2012,354(1-2):239-250
Aims
The objective of this study was to determine the relative importance of transpirational pull, Se speciation, sulfate and species on Se accumulation by plants, in order to determine which of these factors must be considered in the future development of models to predict Se accumulation by plants.Methods
Seedlings of durum wheat (Triticum turgidum L. var durum cv ‘Kyle’) and spring canola (Brassica napus L. var Hyola 401) were grown hydroponically and exposed to SeO 4 2- (selenate) with or without SO 4 2- (sulfate), or to HSeO 3 - (biselenite) under different transpiration regimes altered through ‘low’ (~50%) or ‘high’ (~78%) relative humidity (RH). Plants were harvested after 0, 8, 16, or 24?h exposures, digested, and analyzed for Se by GFAAS.Results
Accumulation and distribution of Se by plants is dependent on plant species, Se speciation in the nutrient solution, SO 4 2- competition, and transpiration regimes. Canola accumulated and translocated more Se than wheat. In wheat and canola, the greatest accumulation and translocation of Se occurred when plants were exposed to SeO 4 2- without SO 4 2- compared to solutions of SeO 4 2- with SO 4 2- or HSeO 3 2- . Wheat plants exposed to SeO 4 2- and SO 4 2- had an increased Se accumulation and translocation under increased transpiration rates than when exposed to SeO 4 2- without SO 4 2- or HSeO 3 2- . On the other hand, increases in transpiration increased the translocation of Se to canola shoots when exposed to HSeO 3 - more than any other treatments.Conclusions
Overall, our results suggest that plant species is the most important factor influencing Se accumulation and translocation, but that these endpoints can be modified by climate and specific soil Se or S content. Models to predict accumulation of Se by plants must consider all of these factors to accurately calculate the mechanisms of uptake and translocation. 相似文献14.
Background and aims
Take-all, caused by the fungus Gaeumannomyces graminis var. tritici, is the most damaging root disease of wheat. A severe attack often leads to premature ripening and death of the plant resulting in a reduction in grain yield and effects on grain quality (Gutteridge et al. in Pest Manag Sci 59:215–224, 2003). Premature death of the plant could also lead to inefficient use of applied nitrogen (Macdonald et al. in J Agric Sci 129(2):125–154, 1997). The aim of this study was to determine crop N uptake and the amount of residual mineral N in the soil after harvest where different severities of take-all had occurred.Methods
Plant and soil samples were taken at anthesis and final harvest from areas showing good and poor growth (later confirmed to be caused by take-all disease) in three winter wheat crops grown on the same soil type on Rothamsted Farm in SE England in 1995, 2007 and 2008 (harvest sampling only). All crops received fertiliser N in spring at recomended rates (190–200?kg?N ha?1). On each ocassion crops were assessed for severity of take-all infection (TAR) and crop N uptakes and soil nitrate plus ammonium (SMN) was determined. Grain yields were also measured.Results
Grain yields (at 85% dry matter) of crops with moderate infection (good crops) ranged from 4.3 to 13.0?t ha?1, compared with only 0.9–4.5?t ha?1 for those with severe infection (poor crops). There were significant (P?<?0.05) negative relationships between crop N uptake and TAR at anthesis and final harvest. At harvest, good crops contained 129–245?kg?N ha?1 in grain, straw and stubble, of which 85–200?kg?N ha?1 was in the grain. In contrast, poor crops contained only 46–121?kg?N ha?1, of which only 22–87?kg?N ha?1 was in the grain. Positive relationships between SMN and TAR were found at anthesis and final harvest. The SMN in the 0–50?cm layer following harvest of poor crops was significantly (P?<?0.05) greater than that under good crops, and most (73–93%) was present as nitrate.Conclusions
Localised patches of severe take-all infection decreased the efficiency with which hexaploid wheat plants recovered soil and fertiliser derived N, and increased the subsequent risk of nitrate leaching. The risk of gaseous N losses to the atmosphere from these areas may also have been enhanced. 相似文献15.
Aliaksandr Kolbas Lilian Marchand Rolf Herzig Erika Nehnevajova Michel Mench 《Plant and Soil》2014,376(1-2):377-397
Background and aims
The potential use of a metal-tolerant sunflower mutant line for both biomonitoring and phytoremediating a Cu-contaminated soil series was investigated.Methods
The soil series (21–1,170 mg Cu kg?1) was sampled in field plots at control and wood preservation sites. Sunflowers were cultivated 1 month in potted soils under controlled conditions.Results
pH and dissolved organic matter influenced Cu concentration in the soil pore water. Leaf chlorophyll content and root growth decreased as Cu exposure rose. Their EC10 values corresponded to 104 and 118 μg Cu L?1 in the soil pore water, 138 and 155 mg Cu kg?1 for total soil Cu, and 16–18 mg Cu kg?1 DW shoot. Biomass of plant organs as well as leaf area, length and asymmetry were well correlated with Cu exposure, contrary to the maximum stem height and leaf water content.Conclusions
Physiological parameters were more sensitive to soil Cu exposure than the morphological ones. Bioconcentration and translocation factors and distribution of mineral masses for Cu highlighted this mutant as a secondary Cu accumulator. Free Cu2+ concentration in soil pore water best predicted Cu phytoavailability. The usefulness of this sunflower mutant line for biomonitoring and Cu phytoextraction was discussed. 相似文献16.
Rita M. Godinho Carlos Vale Miguel Caetano Luis C. Alves Teresa Pinheiro 《Plant and Soil》2014,376(1-2):129-137
Aim
This study presents a micrometre-scale map of the elemental distribution within roots and surrounding sediment of Halimione portulacoides of a contaminated salt marsh in the Tagus estuary.Methods
Microprobe particle induced X-ray emission analysis was performed in sediment slices containing roots with tubular rhizoconcretions attached to host sediments.Results
Strong concentration gradients were found particularly in the inner part of rhizoconcretions adjacent to the root wall. Local enrichment was observed in sediment interstices with Fe precipitates and other associated elements. A maximum of 55 % of Fe was measured near the concretion–root interface, with a decrease to <5 % in the host sediment. Maximum concentrations of P (3 %), As (1,200 μg g?1) and Zn (3,000 μg g?1) were registered in concretions, one order of magnitude above the values of the host sediment. The elemental concentration profiles across roots showed that the epidermis was an efficient selective barrier to the entrance of elements. Fe and As were retained in the epidermis. The highest Cu and Zn concentrations were also observed in the epidermis. However, the concentrations of Mn, Cu and Zn increased in the inner root.Conclusions
As and Fe were mostly retained in the concretion, whereas P, Mn, Cu and Zn were mobilised by the root. 相似文献17.
Seed priming with iron and zinc in bread wheat: effects in germination,mitosis and grain yield 总被引:1,自引:0,他引:1
Currently, the biofortification of crops like wheat with micronutrients such as iron (Fe) and zinc (Zn) is extremely important due to the deficiencies of these micronutrients in the human diet and in soils. Agronomic biofortification with Fe and Zn can be done through different exogenous strategies such as soil application, foliar spraying, and seed priming. However, the excess of these micronutrients can be detrimental to the plants. Therefore, in the last decade, a high number of studies focused on the evaluation of their phytotoxic effects to define the best strategies for biofortification of bread wheat. In this study, we investigated the effects of seed priming with different dosages (1 mg L?1 to 8 mg L?1) of Fe and/or Zn in germination, mitosis and yield of bread wheat cv. ‘Jordão’ when compared with control. Overall, our results showed that: micronutrient dosages higher than 4 mg L?1 negatively affect the germination; Fe and/or Zn concentrations higher than 2 mg L?1 significantly decrease the mitotic index and increase the percentage of dividing cells with anomalies; treatments performed with 8 mg L?1 of Fe and/or 8 mg L?1 Zn caused negative effects in germination, mitosis and grain yield. Moreover, seed priming with 2 mg L?1 Fe?+?2 mg L?1 Zn has been shown to be non-cytotoxic, ensuring a high rate of germination (80%) and normal dividing cells (90%) as well as improving tillering and grain yield. This work revealed that seed priming with Fe and Zn micronutrients constitutes a useful and alternative approach for the agronomic biofortification of bread wheat. 相似文献
18.
Phosphorus supply enhances the response of legumes to elevated CO2 (FACE) in a phosphorus-deficient vertisol 总被引:1,自引:0,他引:1
Background & aims
Understanding the mechanism of how phosphorus (P) regulates the response of legumes to elevated CO2 (eCO2) is important for developing P management strategies to cope with increasing atmospheric CO2 concentration. This study aimed to explore this mechanism by investigating interactive effects of CO2 and P supply on root morphology, nodulation and soil P fractions in the rhizosphere.Methods
A column experiment was conducted under ambient (350?ppm) (aCO2) and eCO2 (550?ppm) in a free air CO2 enrichment (FACE) system. Chickpea and field pea were grown in a P-deficient Vertisol with P addition of 0–16?mg?P?kg?1.Results
Increasing P supply increased plant growth and total P uptake with the increase being greater under eCO2 than under aCO2. Elevated CO2 increased root biomass and length, on average, by 16?% and 14?%, respectively. Nodule biomass increased by 46?% in response to eCO2 at 16?mg P kg?1, but was not affected by eCO2 at no P supply. Total P uptake was correlated with root length while N uptake correlated with nodule number and biomass regardless of CO2 level. Elevated CO2 increased the NaOH-extractable organic P by 92?% when 16?mg P kg?1 was applied.Conclusion
The increase in P and N uptake and nodule number under eCO2 resulted from the increased biomass production, rather than from changes in specific root-absorbing capability or specific nodule function. Elevated CO2 appears to enhance P immobilization in the rhizosphere. 相似文献19.
Govindan Velu Ravi P. Singh Maria Elena Cardenas Bihua Wu Carlos Guzman Ivan Ortiz-Monasterio 《Acta Physiologiae Plantarum》2017,39(9):212
At least two billion people around the world suffer from micronutrient deficiency, or hidden hunger, which is characterized by iron-deficiency anemia, vitamin A and zinc deficiency. As a key staple food crop, wheat provides 20% of the world’s dietary energy and protein, therefore wheat is an ideal vehicle for biofortification. Developing biofortified wheat varieties with genetically enhanced levels of grain zinc (Zn) and iron (Fe) concentrations, and protein content provides a cost-effective and sustainable solution to the resource-poor wheat consumers. Large genetic variation for Fe and Zn were found in the primitive and wild relatives of wheat, the potential high Zn and Fe containing genetic resources were used as progenitors to breed high-yielding biofortified wheat varieties with 30–40% higher Zn content. Grain protein content (GPC) determines processing and end-use quality of wheat for making diverse food products. The GPC-B1 allele from Triticum turgidum L. var. dicoccoides have been well characterized for the increase in GPC and the associated pleiotropic effect on grain Zn and Fe concentrations in wheat. In this study effect of GPC-B1 allele on grain Zn and Fe concentrations in wheat were measured in different genetic backgrounds and two different agronomic management practices (with- and without foliar Zn fertilization). Six pairs of near-isogenic lines differing for GPC-B1 gene evaluated at CIMMYT, Mexico showed that GPC-B1 influenced marginal increase for grain Zn, Fe concentrations, grain protein content and slight reduction in kernel weight and grain yield. However, the magnitude of GPC and grain Zn and Fe reductions varied depending on the genetic background. Introgression of GPC-B1 functional allele in combination with normal or delayed maturity alleles in the CIMMYT elite wheat germplasm has the potential to improve GPC and grain Zn and Fe concentrations without the negative effect on grain yield due to early senescence and accelerated maturity. 相似文献
20.
Lisha Chen Xiaoyan Liu Xinying Zhang Shanshan Liu Jing Wei Gang Xu 《Plant and Soil》2013,368(1-2):355-363