Accumulation In Plant Organs Research Articles

Improvement effects of cytokinin on EDTA assisted phytoremediation and the associated environmental risks

Soil samples containing excess Cd (0.82 mg kg−1), Pb (92.7 mg kg−1) and Cu (72.7 mg kg−1) relative to their corresponding safe thresholds (0.3, 80 and 50 mg kg−1, respectively) from a notorious e-waste disposing and recycling place in southern China were phytoremediated with EDTA addition to evaluate the promotion effects of cytokinin on the remediation efficiency of Eucalyptus globulus. Biomass production of the plant, evapotranspiration amount of the soil, metals accumulation in plant organs and the volume of leachate under various treatments were compared. Relative to the planting control, EDTA application shortened the time required for Cd, Pb and Cu decontamination by 1.7–5.5 times but led to significantly more leachate (996 vs 1256 mL), indicating the negative influence of the chelate treatment on the species and the surrounding environment. The foliar application of cytokinin can expand the advantage and alleviate the adverse impact of individual EDTA application simultaneously as manifested by the increased biomass yield, less time consumption for purification and decreased leachate volume. Cytokinin accelerated the transpiration rate of the plant proved by the least volume of leachate in individual cytokinin treatment. The major factors for effective phytoremediation were the resistance of species to high concentrations of contaminants and less environmental risks generation during the remediation processes. Therefore, synergistic use of such components provides more efficient decontamination of metals and more security for the environment.

Diverging temperature responses of CO2 assimilation and plant development explain the overall effect of temperature on biomass accumulation in wheat leaves and grains.

There is a growing consensus in the literature that rising temperatures influence the rate of biomass accumulation by shortening the development of plant organs and the whole plant and by altering rates of respiration and photosynthesis. A model describing the net effects of these processes on biomass would be useful, but would need to reconcile reported differences in the effects of night and day temperature on plant productivity. In this study, the working hypothesis was that the temperature responses of CO2 assimilation and plant development rates were divergent, and that their net effects could explain observed differences in biomass accumulation. In wheat (Triticum aestivum) plants, we followed the temperature responses of photosynthesis, respiration and leaf elongation, and confirmed that their responses diverged. We measured the amount of carbon assimilated per "unit of plant development" in each scenario and compared it to the biomass that accumulated in growing leaves and grains. Our results suggested that, up to a temperature optimum, the rate of any developmental process increased with temperature more rapidly than that of CO2 assimilation and that this discrepancy, summarised by the CO2 assimilation rate per unit of plant development, could explain the observed reductions in biomass accumulation in plant organs under high temperatures. The model described the effects of night and day temperature equally well, and offers a simple framework for describing the effects of temperature on plant growth.

Organic amendments enhance Pb tolerance and accumulation during micropropagation of Daphne jasminea

The study investigated the effects of organic amendments: pineapple pulp (PP) and agar hydrolyzate (AH), on micropropagation and Pb bioaccumulation and tolerance in a woody shrub Daphne jasminea cultured in vitro. The amendments were analyzed for their content of carbohydrates, phenolic acids, and phytohormones and added at a dose of 10 mL L−1 to the medium containing 1.0 mM lead nitrate. Micropropagation coefficient increased by 10.2–16.6 % in PP and AH variants, respectively. Growth tolerance index increased by 22.9–31.8 % for the shoots and by 60.1–82.4 % for the roots. In the absence of Pb, the additives inhibited multiplication and growth of microplantlets. PP and AH facilitated Pb accumulation in plant organs, especially in the roots. PP enhanced bioconcentration factor and AH improved Pb translocation to the shoots. Adaptation to Pb was associated with increased accumulation of phenolics and higher radical scavenging activity. Medium supplementation, particularly with AH, enhanced antiradical activity of Pb-adapted lines but reduced the content of phenolic compounds. The study results indicated that supplementation with organic amendments may be beneficial in in vitro selection against lead toxicity.

Effect of cadmium on physiological parameters of cereal and millet plants—A comparative study

ABSTRACTMetal load is an abiotic stress that becomes stronger by continual industrial production, wastage, and long-range transport of contaminants. It deteriorates the conditions of agricultural soil that leads to lower growth of cereals as well as decreasing nutritional value of harvested grains. Cadmium (Cd) entry by food chain also affects the health of population. The present study is focused on finding out the superior cereal variety under increasing Cd regime. The plants were grown in increasing Cd levels (0–1000 µM) in the medium and were investigated on 15th day of the exposure. Various parameters like antioxidative enzymes and osmoprotectant levels were studied in both roots and shoots. Cd accumulation in plant organs was determined by atomic absorption spectrophotometry (AAS). Analysis of stress tolerance mechanisms through reactive oxygen species (ROS) scavenging and better partitioning of Cd in roots indicated kodo millet to be more stress tolerant than wheat.

Heavy Metal Accumulation as Phytoremediation Potential of Aquatic Macrophyte, Monochoria vaginalis (Burm.F.) K. Presl Ex Kunth

Bioaccumulation potential of six ecotypes, collected from six different industrial zones of lower Indo-Gangetic basin of West Bengal, India,of Monochoria vaginalis, commonly known as oval-leafed pondweed has been investigated based on chromium (Cr), cadmium (Cd) andCopper (Cu) accumulation pattern in different plant organs. Bioaccumulation potential was assessed by bioaccumulation factors (BFs-leavesmetal concentration/soil metal concentration), bioconcentration factors (BCFs- roots metal/soil metal), transfer factors (TFs-leaves +rhizomes/roots) and enrichment factors (EFs-metals in edible parts/soil metal). Accumulation pattern significantly differed among ecotypes,and accumulation in plant organs was highly metal-specific. BFs for Cr and Cd were >>1 in most of the ecotypes while high TFs (>>1) werenoticed in six ecotypes for Cr and Cu. BCFs was >>1 in all the ecotypes for Cd accumulation only. EFs values for the three metals hoveredaround 1 but it was > 1.0 for Cu in all the six ecotypes. The results suggested that Cr and Cu predominantly accumulated in leaves and rhizomeswhile Cd was predominantly sequestered in roots of M. vaginalis ecotypes. Cu, a redox active metal, showed higher capability than Cd and Crto accumulate in edible parts. In the present study, potential plant parts in M. vaginalis have been identified as bioaccumulation organs withoutany apparent symptoms of toxicity which can be used as phytoremediation of heavy metal contamination in aquatic ecosystems of lower Indo-Gangetic basin of India.DOI: http://dx.doi.org/10.3126/ijasbt.v3i1.12193 Int J Appl Sci Biotechnol, Vol. 3(1): 9-15

Enhancing nitrogen utilization and soil nitrogen balance in paddy fields by optimizing nitrogen management and using polyaspartic acid urea

In this study, we aimed to investigate the effects of nitrogen (N) management and polyaspartic acid urea (PASP-urea) on N utilization and soil N balance of midseason rice in southwest China. Field experiments with no N treatment, famer's fertilizer practice (FFP), three optimized nitrogen managements (ONMs), and three PASP-urea treatments (PASPTs) were conducted at Shehong and Wenjiang, Sichuan Province, in 2013. The results showed that the N fertilizer increased crop N uptake and total N output, but intensified the apparent N losses. Compared to FFP, ONMs and PASPTs (excluding ONM2 and PASPT1 at Shehong) increased N accumulation in plant organs before anthesis, which significantly (p<0.05) increased crop N uptake and N recovery efficiency (NRE), but reduced N production efficiency and N physiological efficiency (NPE), as well as apparent N losses at both the sites. However, the effectiveness of N treatments on N utilization and soil N balance was associated with the initial soil Nmin (amount of inorganic N accumulation). ONM3 (a 15% increase in the N rate over that used in the FFP) increased N accumulation, NRE, and N agronomy efficiency (NAE) of rice at Shehong, whereas ONM2 (a 15% reduction in the N rate over that used in the FFP) reduced N loss but significantly (p<0.05) increased NPE, NAE, and N partial factor productivity at Wenjiang. PASP-urea, especially PASPT3 (PASP urea spilt-applied in four stages), significantly (p<0.05) reduced apparent N surplus before anthesis and N deficit after anthesis, resulting in higher crop N uptake and N use efficiency. Therefore, split-application of N at an optimal rate and PASP-urea could improve the balance between plant N requirement and N input and thus enhance N use efficiency and/or reduce N losses.

Effect of Manure and Bio-fertilizers on Growth, Yield, Silymarin content, and protein expression profile of Silybummarianum.

The impact of the bio-fertilizer (humic acid, EM and yeast), organic fertilizer (cattle and chicken residues) and a combination of both on the growth and yield of Silybum marianum were studied. Plant height, number of branches, number of roots, root length and dry matter accumulation in plant organs significantly increased with the application of bio-fertilizer in combination with organic one. Both bio -fertilizers, organic fertilizer significantly affected the dry weight of herbs and root of Silybum marianumas compared with the control treatments. The plants treated with 10m 3 cattle ma- nure /fed plus EM or 10 m 3 Chicken manure showed significantly higher silymarin content in the second season as com- pared with the other bio , manure fertilization and control treatments . SDS-PAGE analysis of total cellular proteins was used for detecting changes in gene expression on dry seeds. The data showed no variation in protein pattern in terms of number of bands and their relative intensities among all the studied treatments .

Aluminum and the human diet revisited

Concerns about aluminum (Al) exposure in the human diet have persisted for one century. We suggest that continued research would benefit from better reporting of environmental factors that are known to influence Al accumulation in plant organs that are consumed, focusing on subsets of the general public that exhibit the highest risk for neuropathological responses, increased evaluation of commercial processing procedures that may concentrate Al or other toxic substances, and designing studies with low dose, chronic exposure rather than further study of acute, brief exposure.

Augmenting drought tolerance in sorghum by silicon nutrition

Silicon (Si) distribution and accumulation in plant organs is widely reported as beneficial to overcome biotic and abiotic stresses. The investigation on distribution of Si in plant organs under water stress conditions was studied through experiments conducted at Arid Agriculture University, Pakistan during 2007–2009. Treatments (Si200: 200 ml l−1 of potassium silicate and Si0: control or absence of silicon) were replicated thrice with two sorghum cultivars; SPV462 (drought susceptible) and Johar-1 (drought tolerant) screened using osmotic media of PEG-6000 (−4.0, −6.0, −8.0 and −10.0 MPa). The results exhibited increased leaf water potential, leaf area index, SPAD chlorophyll with increased silicon concentration in leaves and roots of drought-tolerant genotype as compared to SPV462. Johar-1 exhibited maximum values for net assimilation and relative growth rate under silicon treatment in comparison to silicon absence. Similarly, maintenance of transpiration rate, because of accumulation of silicon in leaves resulted in optimum leaf water potential and optimum growth of crop.

Maize plant growth and accumulation of photosynthetic pigments at short- and long-term exposure to cadmium

A wide range of cadmium concentrations (from 4 to 200 μM for seedlings and up to 2 mM for germinating kernels) was used to assess Cd toxic effects on maize (Zea mays L.) plants at the different developmental stages: germinating kernels, seedlings (4–9 days), and juvenile plants (34 days). Cd accumulation in plant organs was followed, and its lethal concentration was elucidated. In maize, cadmium was accumulated predominantly in roots; in shoots it was mainly accumulated in the lower leaves, and the higher was leaf position the lower was Cd content in it. At high concentrations (80 and 200 μM), kernels became the substantial cadmium depot. Germinating kernels manifested the lowest sensitivity to cadmium; seedlings were more sensitive; the inhibition of juvenile plant growth attained 90% and more. In the tested range of concentrations, cadmium suppressed shoot mass accumulation harder than that of roots. In 34-day-old plants, water content in shoots was stronger reduced than in roots. Plant death was also manifested earlier in shoots. It was concluded that maize plant sensitivity to cadmium increases with plant growing and that, under conditions of normal mineral nutrition, cadmium inhibits shoot growth more severe than root growth.

海水による冠水が東日本太平洋沿岸域に分布する樹種の生理・生存におよぼす影響 II 樹体内の塩集積

海水による冠水が東日本太平洋沿岸域に分布する樹種の生理・生存におよぼす影響 II 樹体内の塩集積

Effects of drought and nitrogen addition on photosynthetic characteristics and resource allocation of Abies fabri seedlings in eastern Tibetan Plateau

Abies fabri (Mast.) Craib is an endemic and dominant species in typical sub-alpine dark coniferous forests distributed in mountainous regions of the eastern Tibetan Plateau, China. We investigated the ecophysiological responses of A. fabri seedlings to short-term artificially-applied drought, nitrogen addition alone, and the combination of these treatments. Drought was created by excluding natural precipitation with an automatically controlled plastic roof that covered the seedlings. Nitrogen fertilization was applied weekly by spraying over seedlings with ammonium nitrate solution. Experiment results showed that drought caused a reduction in photosynthetic nitrogen use efficiency and leaf mass per area. Nitrogen addition enhanced photosynthetic performance by increasing net photosynthetic rate. In the drought plots, nitrogen addition increased net photosynthetic rate and instantaneous water use efficiency. These results showed that applied nitrogen improved plant water use efficiency and N accumulation in plant organs under drought conditions. Especially under drought conditions more N was concentrated into needles by applied nitrogen as compared with other organs. In conclusion, our results indicated that the combination of nitrogen addition and drought may result in positive effects on A. fabri seedlings in the short-term.

Accumulation and quantitative estimates of airborne lead for a wild plant ( Aster subulatus)

Foliar uptake of airborne lead is one of the pathways for Pb accumulation in plant organs. However, the approximate contributions of airborne Pb to plant organs are still unclear. In the present study, aerosols (nine-stage size-segregated aerosols and total suspended particulates), a wild plant species ( Aster subulatus) and the corresponding soils were collected and Pb contents and isotopic ratios in these samples were analyzed. Average concentration of Pb was 96.5 ± 63.5 ng m −3 in total suspended particulates (TSP) and 20.4 ± 5.5 ng m −3 in the fine fractions of size-segregated aerosols (SSA) (<2.1 μm), higher than that in the coarser fractions (>2.1 μm) (6.38 ± 3.71 ng m −3). Enrichment factors show that aerosols and soils suffered from anthropogenic inputs and the fine fractions of the size-segregated aerosols enriched more Pb than the coarse fractions. The order of Pb contents in A. subulatus was roots > leaves > stems. The linear relationship of Pb isotope ratios ( 206Pb/ 207Pb and 208Pb/ 206Pb) among soil, plant and aerosol samples were found. Based on the simple binary Pb isotopic model using the mean 206Pb/ 207Pb ratios in TSP and in SSA, the approximate contributions of airborne Pb into plant leaves were 72.2% and 65.1%, respectively, suggesting that airborne Pb is the most important source for the Pb accumulation in leaves. So the combination of Pb isotope tracing and the simple binary Pb isotope model can assess the contribution of airborne Pb into plant leaves and may be of interest for risk assessment of the exposure to airborne Pb contamination.

Arbuscular mycorrhizal fungi restore normal growth in a white poplar clone grown on heavy metal-contaminated soil, and this is associated with upregulation of foliar metallothionein and polyamine biosynthetic gene expression.

It is increasingly evident that plant tolerance to stress is improved by mycorrhiza. Thus, suitable plant-fungus combinations may also contribute to the success of phytoremediation of heavy metal (HM)-polluted soil. Metallothioneins (MTs) and polyamines (PAs) are implicated in the response to HM stress in several plant species, but whether the response is modulated by arbuscular mycorrhizal fungi (AMF) remains to be clarified. The aim of the present study was to check whether colonization by AMF could modify growth, metal uptake/translocation, and MT and PA gene expression levels in white poplar cuttings grown on HM-contaminated soil, and to compare this with plants grown on non-contaminated soil. In this greenhouse study, plants of a Populus alba clone were pre-inoculated, or not, with either Glomus mosseae or G. intraradices and then grown in pots containing either soil collected from a multimetal- (Cu and Zn) polluted site or non-polluted soil. The expression of MT and PA biosynthetic genes was analysed in leaves using quantitative reverse transcription-PCR. Free and conjugated foliar PA concentrations were determined in parallel. On polluted soil, AMF restored plant biomass despite higher Cu and Zn accumulation in plant organs, especially roots. Inoculation with the AMF caused an overall induction of PaMT1, PaMT2, PaMT3, PaSPDS1, PaSPDS2 and PaADC gene expression, together with increased free and conjugated PA levels, in plants grown on polluted soil, but not in those grown on non-polluted soil. Mycorrhizal plants of P. alba clone AL35 exhibit increased capacity for stabilization of soil HMs, together with improved growth. Their enhanced stress tolerance may derive from the transcriptional upregulation of several stress-related genes, and the protective role of PAs.

Effect of different Fe(III) compounds on photosynthetic electron transport in spinach chloroplasts and on iron accumulation in maize plants

AbstractSynthesis and spectral characteristics of [Fe(nia)3Cl3] and [Fe(nia)3(H2O)2](ClO4)3 are described. The effect of these compounds as well as of FeCl3·6H2O on photosynthetic electron transport in spinach chloroplasts was investigated using EPR spectroscopy. It was found that due to the interaction of these compounds with tyrosine radicals situated at the 161st position in D1 (TyrZ) and D2 (TyrD) proteins located at the donor side of photosystem (PS) II, electron transport between the photosynthetic centres PS II and PS I was interrupted. In addition, the treatment with [Fe(nia)3(H2O)2](ClO4)3 resulted in a release of Mn(II) from the oxygen evolving complex situated on the donor side of PS II. Moreover, the effect of the Fe(III) compounds studied on some production characteristics of hydroponically cultivated maize plants and on Fe accumulation in plant organs was investigated. In general, the production characteristic most inhibited by the presence of Fe(III) compounds was the leaf dry mass and [Fe(nia)3(H2O)2](ClO4)3 was found to be the most effective compound. The highest Fe amount was accumulated in the roots, and the leaves treated with Fe(III) compounds contained more Fe than the stems. The treatment with FeCl3·6H2O caused the most effective translocation of Fe into the shoots. Comparing the effect of nicotinamide complexes, [Fe(nia)3(H2O)2](ClO4)3 was found to facilitate the translocation of Fe into the shoots more effectively than [Fe(nia)3Cl3]. This could be connected with the different structure of these complexes. [Fe(nia)3(H2O)2](ClO4)3 has ionic structure and, in addition, coordinated H2O molecules can be easily substituted by other ligands.

Comparison of tolerance of Brassica juncea and Vigna radiata to cadmium

The effect of different cadmium concentrations (6–120 µM) on Hill reaction activity (HRA) of isolated chloroplasts, contents of chlorophylls (Chls) and carotenoids (Cars), and Cd uptake and accumulation in plant organs of Indian mustard (Brassica juncea L. cv. Vitasso) and mung bean [Vigna radiata (L.) Wilczek] were determined. The Cd stress inhibited photochemical activity of isolated chloroplasts of both species and in both tested developmental stages. On the basis of EC50 values, the mung bean showed a higher sensitivity to Cd treatment than Indian mustard. The higher sensitivity of both species was determined in the earlier than in the older developmental stage. The leaves of Cd-treated plants possessed lower contents of Chls and Cars in both species and the negative effect increased with Cd concentration. A difference between species was also found in Cd uptake and accumulation. In both species, Cd was accumulated more in roots than in shoots, with higher accumulation in Indian mustard than in mung bean.

Effect of selenium oxidation state on cadmium translocation in chamomile plants

AbstractSyntheses and spectral characteristics of cadmium(II) compounds (CdSeO4, CdSeO3, and Cd(NCSe)2(nia)2) containing selenium in oxidation states (VI), (IV), and (-II) are described. In Cd(NCSe)2(nia)2, nicotinamide (nia) and selenocyanate anions are bonded to Cd atom as N-donor monodentate ligands. Nicotinamide is coordinated through the ring nitrogen atom. The effects of these selenium compounds as well as Cd(NCS)2(nia)2 on the growth and Cd accumulation in roots and shoots of hydroponically cultivated chamomile plants (cultivar Lutea) were studied. In the applied concentration range (12–60 µmol dm−3) Cd(NCS)2(nia)2 affected neither the length nor the dry mass of roots and shoots. Other compounds applied at 24 µmol dm−3 and 60 µmol dm−3 significantly reduced dry mass of roots and shoots. Selenium oxidation state in the cadmium compounds affected Cd accumulation in plant organs as well as Cd translocation within the plants, which was reflected in the values of bioaccumulation (BAF) and translocation factors (S/R). Cd amount accumulated by shoots was lower than that in the roots. The highest BAF values determined for Cd accumulation in shoots were obtained with CdSeO4. Substitution of S with Se in the Cd(NCX)2(nia)2 (X = Se or S) caused an increase of Cd translocation into the shoots.

Cadmium and copper toxicity for tomato seedlings

We studied cadmium (Cd) and copper (Cu) toxicity in tomato, their accumulation in plant organs and their ability to induce phytochelatin synthesis. The seedlings were cultivated in nutrient solution supplemented with increased concentrations of CdCl 2 or CuSO 4 from 0 to 50 μM. After 7 days of treatment, plants were harvested and the dry weight, the amount of thiobarbituric acid-reactive substances (TBARS). Cd and Cu contents and SH groups rich peptides were determined. We found that Cd and Cu decrease tomato growth, notably at high Cu levels. Cd and Cu concentrations in plant organs increased with applied amounts. Cd and Cu concentrations were the highest in roots. The amount of thiobarbituric acid-reactive substances, that estimate the lipid peroxidation, was increased with heavy metal exposure and was, mainly, higher in roots with Cu treatment.

Influence of Mineral Nutrients on Strawberry Fruit Quality and Their Accumulation in Plant Organs

This review is based partly on complete articles and partly on abstracts. Three of the 60 articles deal with the total uptake of elements in strawberry plant organs in two different strawberry production systems, both considered as optimal concerning amount and balance of elements. The effect on fruit quality may be dramatic if the level of a particular element is outside this range, but there may also be effects initiated by differences within the optimal range of elements. Most articles refer to product oriented quality, but some focus on consumer oriented quality, as discussed by Shewfelt (1999). The discussion here is on a general basis, so one should keep in mind that there are cultivar differences and that specification of nutrition ideally should mirror the needs of a single cultivar, or a group of cultivars with similar requirements. Also, to get a complete understanding of the subject future reviews should embrace a broader access of information including the effect on plant development of individual elements, such as the role of calcium in fruit firmness and its importance in cell wall structure. However, the intention here is to narrow the information to results that suggest a direct connection between nutrient uptake and fruit quality.

Cadmium uptake, localization and detoxification in Zea mays

Cadmium uptake, translocation and localization in maize roots and shoots at the tissue and cellular level were investigated. Metal accumulation in plant organs as well as symptoms of Cd toxicity were closely correlated with an increase in Cd concentration applied (5 - 300 μM). Most of the metal taken up was retained in roots, mainly inside the cells of endodermis, pericycle and central cylinder parenchyma. Accumulation of phytochelatins and related peptides also depended on Cd concentration in the nutrient solution.