Affiner votre recherche
Résultats 1-10 de 15
Impact of elevated CO2 and elevated O3 on Beta vulgaris L.: Pigments, metabolites, antioxidants, growth and yield
2013
Kumari, Sumita | Agrawal, Madhoolika | Tiwari, Supriya
The present study was conducted to assess morphological, biochemical and yield responses of palak (Beta vulgaris L. cv Allgreen) to ambient and elevated levels of CO2 and O3, alone and in combination. As compared to the plants grown in charcoal filtered air (ACO2), growth and yield of the plants increased under elevated CO2 (ECO2) and decreased under combination of ECO2 with elevated O3 (ECO2 + EO3), ambient O3 (ACO2 + AO3) and elevated O3 (EO3). Lipid peroxidation, ascorbic acid, catalase and glutathione reductase activities enhanced under all treatments and were highest in EO3. Foliar starch and organic carbon contents increased under ECO2 and ECO2 + EO3 and reduced under EO3 and ACO2 + AO3. Foliar N content declined in all treatments compared to ACO2 resulting in alteration of C/N ratio. This study concludes that ambient level of CO2 is not enough to counteract O3 impact, but elevated CO2 has potential to counteract the negative effects of future O3 level.
Afficher plus [+] Moins [-]Bioavailability of residual polycyclic aromatic hydrocarbons following enhanced natural attenuation of creosote-contaminated soil
2010
Juhasz, Albert L. | Smith, Euan | Waller, Natasha | Stewart, Richard | Weber, John
The impact of residual PAHs (2250 ± 71 μg total PAHs g−1) following enhanced natural attenuation (ENA) of creosote-contaminated soil (7767 ± 1286 μg total PAHs g−1) was assessed using a variety of ecological assays. Microtox™ results for aqueous soil extracts indicated that there was no significant difference in EC50 values for uncontaminated, pre- and post-remediated soil. However, in studies conducted with Eisenia fetida, PAH bioaccumulation was reduced by up to 6.5-fold as a result of ENA. Similarly, Beta vulgaris L. biomass yields were increased 2.1-fold following ENA of creosote-contaminated soil. While earthworm and plant assays indicated that PAH bioavailability was reduced following ENA, the residual PAH fraction still exerted toxicological impacts on both receptors. Results from this study highlight that residual PAHs following ENA (presumably non-bioavailable to bioremediation) may still be bioavailable to important receptor organisms such as earthworms and plants. Residual PAHs in creosote-contaminated soil following enhanced natural attenuation impacted negatively on ecological receptors.
Afficher plus [+] Moins [-]Fluorogenic compound hydrolysis as a measure of toxicity-induced cytoplasmic viscosity and pH changes
1997
Grabowski, J. | Hsiao KeCheng | Baker, P.R. | Bornman, C.H. (Institute of Physics, Poznan University of Technology, ul. Piotrowo 3, 60-965 Poznan (Poland))
Release of metals from homogeneous soil columns by wastewater from an agricultural industry
1998
Madrid, L. | Diaz-Barrientos, E. (Instituto de Recursos Naturales y Agrobiologia de Sevilla (CSIC), Apartado 1052, E-41080 Sevilla (Spain))
Polynuclear aromatic hydrocarbons in crops from long-term field experiments amended with sewage sludge
1992
Wild, S.R. | Berrow, M.L. | McGrath, S.P. | Jones, K.C. (Institute of Environmental and Biological Sciences, Lancaster University, Lancaster LA1 4YQ (United Kingdom))
Protective effect of Beta vulgaris roots supplementation on anemic phenylhydrazine-intoxicated rats
2021
Abd-El-Fattah, Mohy Eldin | Dessouki, Amina A. | Abdelnaeim, Noha S. | Emam, Bassant M.
Anemia is a public health problem that affects many people worldwide. Beetroot (Beta vulgaris) is a plant supposed to have many healthy features. The present study was done to evaluate the anti-anemic effect of beetroot supplement on anemia induced by phenylhydrazine in albino rats. Fifty rats were randomly divided into five equal groups. The control group was kept normal rats. In the second group, anemia was induced in rats by intraperitoneal injection of phenylhydrazine at 60 mg/kg in 3 divided doses daily, for 3 consecutive days. The last three groups received phenylhydrazine as the anemic group. Then, the third group received beetroot extract in dose 200 mg/kg for 24 days. The fourth group received beetroot powder in dose 1000 mg/kg for 24 days. The last group received iron (III) hydroxide polymaltose complex in dose 5mg/kg for 24 days. Our results showed that hemolytic anemia induced by phenylhydrazine in rats caused alteration in the blood picture, iron indices, serum biochemical parameters, antioxidant biomarkers, and histopathological picture. However, the supplementation with beetroot ameliorated these alterations, especially beetroot powder which showed powerful health effects compared to beetroot extract and iron preparation.
Afficher plus [+] Moins [-]Silver nanoparticles-induced nephrotoxicity in rats: the protective role of red beetroot (Beta vulgaris) juice
2020
Albrahim, Tarfa
The present study was designed to investigate the nephrotoxicity of silver nanoparticles (AgNPs; 80 mg/kg; > 100 nm) and to evaluate the protective effect exercised by Beta vulgaris (beetroot) juice (RBR; 200 mg/kg) on male rats’ kidney. Serum-specific parameters (urea, creatinine, electrolytes and histopathology of kidney tissue) were examined to assess the AgNPs nephrotoxicity effect. Moreover, this study analysed oxidative stress (lipid peroxidation, glutathione, superoxide dismutase and catalase) and anti-apoptotic markers (Bcl-2). AgNPs intoxication increased kidney function marker levels and lipid peroxidation and decreased the glutathione, superoxide dismutase and catalase activities in kidney tissue. Additionally, Bcl-2 expression was downregulated following AgNPs intoxication. Moreover, AgNPs induced a significant increase in renal DNA damage displayed as an elevation in tail length, tail DNA percentage and tail moment. Interestingly, RBR post-treatment restored the biochemical and histological alterations induced by AgNPs exposure, reflecting its nephroprotective effect. Collectively, the present data suggest that RBR could be used as a potential therapeutic intervention to prevent AgNPs-induced nephrotoxicity.
Afficher plus [+] Moins [-]Role of plant growth–promoting rhizobacterial consortium in improving the Vigna radiata growth and alleviation of aluminum and drought stresses
2019
Silambarasan, Sivagnanam | Logeswari, Peter | Cornejo, Pablo | Rajesh Kannan, Velu
Aluminum (Al) is a major constraint for plant growth by inducing inhibition of root elongation in acid soils around the world. Besides, drought is another major abiotic stress that adversely affects growth and productivity of agricultural crops. The plant growth–promoting (PGP) rhizobacterial strains are useful choice to decrease these stressful effects and is now extensively in practice. However, the use of bacterial inoculation has not been attempted for the mitigation of Al stress in plants growing at high Al levels under drought stress. Therefore, in the present study, Al- and drought-tolerant bacterial strains were isolated from Lactuca sativa and Beta vulgaris rhizospheric soils. Among the bacterial isolates, two strains, CAM12 and CAH6, were selected based on their ability to tolerate high levels of Al (8 mM) and drought (15% PEG-6000, w/v) stresses. The bacterial strains CAM12 and CAH6 were identified as Bacillus megaterium and Pantoea agglomerans, respectively, by 16S rRNA gene sequence homology. Moreover, both strains showed multiple PGP traits even in the presence of abiotic stresses. In the pot experiments, inoculation of the strains CAM12 and CAH6 as individually or as included in a consortium improved the Vigna radiata growth under abiotic stress conditions and reduced Al uptake in plants. However, the most effective treatment was seen with bacterial consortium that allowed the plants to tolerate abiotic stress effectively and achieved better growth. These results indicate that bacterial consortium could be used as a bio-inoculant for enhancing V. radiata growth in soil with high Al levels subjected to drought conditions.
Afficher plus [+] Moins [-]Saline irrigation and Zn amendment effect on Cd phytoavailability to Swiss chard (Beta vulgaris L.) grown on a long-term amended agricultural soil: a human risk assessment
2014
Valdez-González, J. C. | López-Chuken, U. J. | Guzmán-Mar, J. L. | Flores-Banda, F. | Hernández-Ramírez, A. | Hinojosa-Reyes, L.
Crops, particularly in the Northeast region of Mexico, have to cope with increasing soil salinization due to irrigation. Chloride (Cl⁻) concentration has been strongly related to enhance cadmium (Cd) uptake by plants due to increased solubility in the soil solution. The effect of irrigation with slightly saline water from a local well was evaluated in this work on the accumulation and translocation of Cd in Swiss chard (Beta vulgaris L.) grown in soil historically amended with stabilized sewage sludge under a regime of phosphorus and zinc fertilization. A factorial pot experiment was conducted with two phosphate fertilizer levels (PF, 0 and 80 kg ha⁻¹dry soil, respectively), two Zn levels (0 and 7 kg ha⁻¹dry soil), and two sources of water for irrigation deionized water (DW) and slightly saline well water (WW) from an agricultural site. Additionally, a human risk assessment for Cd ingestion from plants was assessed. Results showed that Cl⁻salinity in the WW effectively mobilized soil Cd and increased its phytoavailability. A higher level of Cd was found in roots (46.41 mg kg⁻¹) compared to shoots (10.75 mg kg⁻¹). Although the total content of Cd in the edible parts of the Swiss chard irrigated with WW exceeded permissible recommended consumption limit, bioavailable cadmium in the aboveground parts of the plant in relation to the total cadmium content was in the range from 8 to 32 %. Therefore, human health risks might be overestimated when the total concentration is taken into account.
Afficher plus [+] Moins [-]Cumulative impact of GM herbicide-tolerant cropping on arable plants assessed through species-based and functional taxonomies
2009
Squire, G. R. (Geoffrey R) | Hawes, Cathy | Begg, G. S. (Graham S) | Young, Mark W
Background, aim and scope In a gradualist approach to the introduction of crop biotechnology, the findings of experimentation at one scale are used to predict the outcome of moving to a higher scale of deployment. Movement through scales had occurred for certain genetically modified herbicide-tolerant (GMHT) crops in the UK as far as large-scale field trials. However, the land area occupied by these trials was still <1% of the area occupied by the respective non-GM crops. Some means is needed to predict the direction and size of the effect of increasing the area of GMHT cropping on ecological variables such as the diversity among species and trophic interactions. Species-accumulation curves are examined here as a method of indicating regional-scale impacts on botanical diversity from multiple field experiments. Materials and methods Data were used from experiments on the effect of (GMHT) crops and non-GM, or conventional, comparators in fields sown with four crop types (beet, maize, spring and winter oilseed rape) at a total of 250 sites in the UK between 2000 and 2003. Indices of biodiversity were measured in a split-field design comparing GMHT with the farmers' usual weed management. In the original analyses based on the means at site level, effects were detected on the mass of weeds in the three spring crops and the proportion of broadleaf and grass weeds in winter oilseed rape, but not on indices of plant species diversity. To explore the links between site means and total taxa, accumulation curves were constructed based on the number of plant species (a pool of around 250 species in total) and the number of plant functional types (24), inferred from the general life-history characteristics of a species. Results Species accumulation differed between GMHT and conventional treatments in direction and size, depending on the type of crop and its conventional management. Differences were mostly in the asymptote of the curve, indicative of the maximum number of species found in a treatment, rather than the steepness of the curve. In winter oilseed rape, 8% more species were accumulated in the GMHT treatment, mainly as a result of the encouragement of grass species by the herbicide when applied in the autumn. (Overall, GMHT winter oilseed rape had strong negative effects on both the food web and the potential weed burden by increasing the biomass of grasses and decreasing that of broadleaf weeds.) In maize, 33% more species--a substantial increase--were accumulated in the GMHT than in the conventional, consistent with the latter's highly suppressive weed management using triazine herbicides. In the spring oilseed rape and beet, fewer species (around 10%) were accumulated in the GMHT than the conventional. The GMHT treatments did not remove or add any functional (life history) types, however. Differences in species accumulation between treatments appeared to be caused by loss or gain of rarer species. The generality of this effect was confirmed by simulations of species accumulation in which the species complement at each of 50 sites was drawn from a regional pool and subjected to reducing treatment at each site. Shifts in the species-accumulation parameters, comparable to those measured, occurred only when a treatment removed the rarer species at each site. Discussion Species accumulation provided a set of simple curve-parameters that captured the net result of numerous local effects of treatments on plant species and, in some instances, the balance between grass and broadleaf types. The direction of effect was not the same in the four crops and depended on the severity of the conventional treatment and on complex interactions between season, herbicide and crop. The accumulation curves gave an indication of potential positive or negative consequences for regional species pools of replacing a conventional practice with GMHT weed management. In this and related studies, a range of indicators, through which diversity was assessed by both species and functional type, and at both site and regional scales, gave more insight into effects of GMHT treatment than provided by any one indicator. Conclusions Species accumulation was shown to discriminate at the regional scale between agronomic treatments that had little effect on species number at the field scale. While a comprehensive assessment of GM cropping needs to include an examination of regional effects, as here, the costs of doing this in all instances would be prohibitive. Simulations of diversity-reducing treatments could provide a theoretical framework for predicting the likely regional effects from in-field plant dynamics. Recommendations and perspectives Accumulation curves potentially offer a means of linking within-site effects to regional impacts on biodiversity resulting from any change in agricultural practice. To guide empirical measurement, there is a scope to apply a methodology such as individual-based modelling at the field scale to explore the links between agronomic treatments and the relative abundance of plant types. The framework needs to be validated in practice, using species-based and functional taxonomies, the latter defined by measured rather than inferred traits.
Afficher plus [+] Moins [-]