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1.
PLoS Negl Trop Dis ; 17(7): e0011457, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37432968

RESUMO

BACKGROUND: Lymphatic filariasis (LF) is a vector-borne parasitic disease which affects 70 million people worldwide and causes life-long disabilities. In Bangladesh, there are an estimated 44,000 people suffering from clinical conditions such as lymphoedema and hydrocoele, with the greatest burden in the northern Rangpur division. To better understand the factors associated with this distribution, this study examined socio-economic and environmental factors at division, district, and sub-district levels. METHODOLOGY: A retrospective ecological study was conducted using key socio-economic (nutrition, poverty, employment, education, house infrastructure) and environmental (temperature, precipitation, elevation, waterway) factors. Characteristics at division level were summarised. Bivariate analysis using Spearman's rank correlation coefficient was conducted at district and sub-district levels, and negative binomial regression analyses were conducted across high endemic sub-districts (n = 132). Maps were produced of high endemic sub-districts to visually illustrate the socio-economic and environmental factors found to be significant. RESULTS: The highest proportion of rural population (86.8%), poverty (42.0%), tube well water (85.4%), and primary employment in agriculture (67.7%) was found in Rangpur division. Spearman's rank correlation coefficient at district and sub-district level show that LF morbidity prevalence was significantly (p<0.05) positively correlated with households without electricity (district rs = 0.818; sub-district rs = 0.559), households with tube well water (sub-district rs = 0.291), households without toilet (district rs = 0.504; sub-district rs = 0.40), mean annual precipitation (district rs = 0.695; sub-district rs = 0.503), mean precipitation of wettest quarter (district rs = 0.707; sub-district rs = 0.528), and significantly negatively correlated with severely stunted children (district rs = -0.723; sub-district rs = -0.370), mean annual temperature (district rs = -0.633.; sub-district rs = 0.353) and mean temperature (wettest quarter) ((district rs = -0.598; sub-district rs = 0.316) Negative binomial regression analyses at sub-district level found severely stunted children (p = <0.001), rural population (p = 0.002), poverty headcount (p = 0.001), primary employment in agriculture (p = 0.018), households without toilet (p = <0.001), households without electricity (p = 0.002) and mean temperature (wettest quarter) (p = 0.045) to be significant. CONCLUSIONS: This study highlights the value of using available data to identify key drivers associated with high LF morbidity prevalence, which may help national LF programmes better identify populations at risk and implement timely and targeted public health messages and intervention strategies.


Assuntos
Filariose Linfática , Criança , Humanos , Prevalência , Filariose Linfática/epidemiologia , Bangladesh/epidemiologia , Estudos Retrospectivos , Morbidade , Escolaridade
2.
Molecules ; 28(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37049732

RESUMO

Transcutaneous vaccination is one of the successful, affordable, and patient-friendly advanced immunization approaches because of the presence of multiple immune-responsive cell types in the skin. However, in the absence of a preferable facilitator, the skin's outer layer is a strong impediment to delivering biologically active foreign particles. Lipid-based biocompatible ionic-liquid-mediated nanodrug carriers represent an expedient and distinct strategy to permit transdermal drug delivery; with acceptable surfactants, the performance of drug formulations might be further enhanced. For this purpose, we formulated a lipid-based nanovaccine using a conventional (cationic/anionic/nonionic) surfactant loaded with an antigenic protein and immunomodulator in its core to promote drug delivery by penetrating the skin and boosting drug delivery and immunogenic cell activity. In a follow-up investigation, a freeze-dry emulsification process was used to prepare the nanovaccine, and its transdermal delivery, pharmacokinetic parameters, and ability to activate autoimmune cells in the tumor microenvironment were studied in a tumor-budding C57BL/6N mouse model. These analyses were performed using ELISA, nuclei and HE staining, flow cytometry, and other biological techniques. The immunomodulator-containing nanovaccine significantly (p < 0.001) increased transdermal drug delivery and anticancer immune responses (IgG, IgG1, IgG2, CD8+, CD207+, and CD103+ expression) without causing cellular or biological toxicity. Using a nanovaccination approach, it is possible to create a more targeted and efficient delivery system for cancer antigens, thereby stimulating a stronger immune response compared with conventional aqueous formulations. This might lead to more effective therapeutic and preventative outcomes for patients with cancer.


Assuntos
Tensoativos , Vacinas , Camundongos , Animais , Camundongos Endogâmicos C57BL , Sistemas de Liberação de Medicamentos , Administração Cutânea , Antígenos , Adjuvantes Imunológicos/farmacologia , Lipídeos
3.
Data Brief ; 47: 108995, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36875217

RESUMO

Weaving is one of the most popular fabric manufacturing techniques. The weaving process consists of 3 major stages: warping, sizing, and weaving. The weaving factory henceforth involves a lot of data. But unfortunately, there is no attempt to utilize machine learning or data science in weaving production. Although a variety of scopes are there to implement statistical analysis, data science, and machine learning. The dataset was prepared by using the daily production report for 9 months. The final dataset contains 121,148 data with 18 parameters.  Whereas the raw data contains the same number of entries with 22 columns. The raw data needs substantial work to combine the daily production report, treat the missing values, rename columns, and feature engineering to derive EPI, PPI, warp, weft count values, etc. The complete dataset is stored at https://data.mendeley.com/datasets/nxb4shgs9h/1. It is further processed to get the rejection dataset which is stored at https://data.mendeley.com/datasets/6mwgj7tms3/2. The future implementation of the dataset is to predict the weaving waste, investigate the statistical relations among various parameters, production prediction, etc.

4.
ACS Appl Mater Interfaces ; 14(50): 55332-55341, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36508194

RESUMO

The transdermal delivery of hydrophilic drugs remains challenging owing to their poor ability to permeate the skin; formulation with oil media is difficult without adding chemical permeation enhancers or co-solvents. Herein, we synthesized 12 oil-miscible ionic liquid (IL) drugs comprising lidocaine-, imipramine-, and levamisole (Lev)-hydrochloride with fatty acid permeation enhancers, i.e., laurate, oleate, linoleate, and stearate as counterions. A set of in vitro and in vivo studies was performed to investigate the potency and deliverability of the transdermal drug formulations. All of the synthesized compounds were freely miscible with pharmaceutically acceptable solvents/agents (i.e., ethanol, N-methyl pyrrolidone, Tween 20, and isopropyl myristate (IPM)). In vitro permeation studies revealed that the oleate-based Lev formulation had 2.6-fold higher skin permeation capability than the Lev salts and also superior ability compared with the laurate-, linoleate-, and stearate-containing samples. Upon in vivo transdermal administration to mice, the peak plasma concentration, elimination half-life, and area under the plasma concentration curve values of Lev-IL were 4.6-, 2.9-, and 5.4-fold higher, respectively, than those of the Lev salt. Furthermore, in vitro skin irritation and in vivo histological studies have demonstrated that Lev-IL has excellent biocompatibility compared with a conventional ionic liquid-based carrier. The results indicate that oil-miscible IL-based drugs provide a simple and scalable strategy for the design of effective transdermal drug delivery systems.


Assuntos
Líquidos Iônicos , Camundongos , Animais , Administração Cutânea , Líquidos Iônicos/química , Absorção Cutânea , Estearatos , Lauratos , Ácido Linoleico , Ácido Oleico/farmacologia , Pele , Portadores de Fármacos/química , Solventes , Permeabilidade , Sistemas de Liberação de Medicamentos/métodos
5.
ACS Appl Bio Mater ; 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36043942

RESUMO

Research on the role of reactive oxygen species (ROS) in the aging process has advanced significantly over the last two decades. In light of recent findings, ROS takes part in the aging process of cells along with contributing to various physiological signaling pathways. Antioxidants being cells' natural defense mechanism against ROS-mediated alteration, play an imperative role to maintain intracellular ROS homeostasis. Although the complete understanding of the ROS regulated aging process is yet to be fully comprehended, current insights into various sources of cellular ROS and their correlation with the aging process and age-related diseases are portrayed in this review. In addition, results on the effect of antioxidants on ROS homeostasis and the aging process as well as their advances in clinical trials are also discussed in detail. The future perspective in ROS-antioxidant dynamics on antiaging research is also marshaled to provide future directions for ROS-mediated antiaging research fields.

6.
ACS Appl Bio Mater ; 5(6): 2431-2460, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35583460

RESUMO

The COVID-19 pandemic caused by the SARS-CoV-2, a ribonucleic acid (RNA) virus that emerged less than two years ago but has caused nearly 6.1 million deaths to date. Recently developed variants of the SARS-CoV-2 virus have been shown to be more potent and expanded at a faster rate. Until now, there is no specific and effective treatment for SARS-CoV-2 in terms of reliable and sustainable recovery. Precaution, prevention, and vaccinations are the only ways to keep the pandemic situation under control. Medical and scientific professionals are now focusing on the repurposing of previous technology and trying to develop more fruitful methodologies to detect the presence of viruses, treat the patients, precautionary items, and vaccine developments. Nanomedicine or nanobased platforms can play a crucial role in these fronts. Researchers are working on many effective approaches by nanosized particles to combat SARS-CoV-2. The role of a nanobased platform to combat SARS-CoV-2 is extremely diverse (i.e., mark to personal protective suit, rapid diagnostic tool to targeted treatment, and vaccine developments). Although there are many theoretical possibilities of a nanobased platform to combat SARS-CoV-2, until now there is an inadequate number of research targeting SARS-CoV-2 to explore such scenarios. This unique mini-review aims to compile and elaborate on the recent advances of nanobased approaches from prevention, diagnostics, treatment to vaccine developments against SARS-CoV-2, and associated challenges.


Assuntos
COVID-19 , Nanoestruturas , COVID-19/prevenção & controle , Vacinas contra COVID-19/uso terapêutico , Humanos , Nanoestruturas/uso terapêutico , Pandemias/prevenção & controle , SARS-CoV-2/genética , Desenvolvimento de Vacinas
7.
ACS Appl Bio Mater ; 5(6): 2586-2597, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35472266

RESUMO

Transdermal drug delivery systems (TDDSs) may be useful for preventing various diseases including cancer. However, the stratum corneum (SC) inhibits the permeation of foreign particles into the skin. To obtain an effective TDDS, we developed a protein-containing nanocarrier (PCNC) comprising an antigenic protein (ovalbumin/OVA) stabilized by a combination of surfactants, i.e., a lipid-based surface-active ionic liquid and Tween-80. The PCNC was lyophilized to remove water and cyclohexane and then dispersed in isopropyl myristate. It is biocompatible both in vitro and in vivo, and is suitable for use in a therapeutic TDDS. The skin permeability of the PCNC was significantly (p < 0.0001) enhanced, and the transdermal distribution and transdermal flux of the OVA delivery system were 25 and 28 times greater, respectively, than those of its aqueous formulation. The PCNC disrupted the order of lipid orientation in the skin's SC and increased intercellular protein delivery. It demonstrated effective antitumor activity, drastically (p < 0.001) suppressed tumor growth, increased mouse survival rates, and significantly (p < 0.001) stimulated the OVA-specific tumor immune response. The PCNC also increased the number of cytotoxic T cells expressing CD8 antibodies on their surfaces (CD8 + T-cells) in the tumor microenvironment. These findings suggest that PCNCs may be promising biocompatible carriers for transdermal antigenic protein delivery in tumor immunotherapy.


Assuntos
Líquidos Iônicos , Administração Cutânea , Animais , Imunoterapia , Líquidos Iônicos/metabolismo , Camundongos , Proteínas/metabolismo , Pele , Absorção Cutânea , Água/metabolismo
8.
Heliyon ; 8(1): e08771, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35128091

RESUMO

Momordica dioica (M. dioica) is a gourd like blooming plant that is readily available in Bangladesh, requiring biological research to discover its therapeutic values. The goal of our research was to see if the ethanolic extract of this plant had any anti-hyperglycemic properties. Water, glibenclamide and M. dioica extracts were fed to Streptozocin induced type-2 diabetic rat models at a dose of 1.25 g/kg body weight (bw) for 28 days to see what kind of effects they had on serum glucose, insulin, liver glycogen and lipid contents. Except for the control group, all the groups followed a pattern of maintaining the body weight. The oral glucose tolerance test was observed to be improved in extract after 14 days of the experiment. When assessed with the control group, the M. dioica extract showed a significant (p = 0.0015) decrease in postprandial serum glucose level (M±SD, mmol/l, 13.23 ± 1.03 control Vs 11.47 ± 2.21 extract) at 120 min. The treatment of diabetic model rats with extract resulted in a 7% (p < 0.0001) reduction in serum cholesterol levels. While subsequent 28 days of treatment, insulin levels were found to be lowered in all groups (from 246.76 to 200.44 pg/dL; p < 0.0001 for standard and from 309.01 to 204.61 pg/dL; p < 0.0001 for sample). The results revealed that prolonged administration of M. dioica improved the glycemic and lipidemic state of type-2 diabetic rats, implying that more research is needed to identify the active ingredient (s).

9.
Plants (Basel) ; 10(11)2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34834910

RESUMO

Integrated Plant Nutrient System (IPNS) is practiced worldwide to maintain soil quality. Two field experiments were conducted in 2019 and 2020 in acidic and charland soils to assess the impact of different manures, viz., poultry manure (PM), vermicompost (VC), compost (OF), rice husk biochar (RHB), poultry manure biochar (PMB)-based IPNS, and dolomite over control on productivity and nitrogen use efficiency (NUE) of the Mustard-Boro-Transplanted Aman and Maize-Jute-Transplanted Aman cropping patterns, and on soil properties. The experiments were laid out in a randomized complete block design with four replications. The results showed that IPNS treatments significantly improved soil aggregate properties and total nitrogen in acidic soil, and bulk density in charland soil. In both years, IPNS treatments increased system productivity from 55.4 to 82.8% in acidic soil and from 43.3 to 115.4% in charland soil over that of control. IPNS and dolomite treatments increased nitrogen uptake from 35.5 to 105.7% over that of control and NUE in both soils in 2019 and 2020. PMB- and OF-based INPS treatments exhibited superior performances in both soils, and the impact was more prominent in 2020. Therefore, PMB- and OF-based IPNS can be recommended for maximizing system productivity and NUE with concurrent improvement of physicochemical properties of acidic and charland soils.

10.
ACS Appl Mater Interfaces ; 13(36): 42461-42472, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34460218

RESUMO

Since injection administration for diabetes is invasive, it is important to develop an effective transdermal method for insulin. However, transdermal delivery remains challenging owing to the strong barrier function of the stratum corneum (SC) of the skin. Here, we developed ionic liquid (IL)-in-oil microemulsion formulations (MEFs) for transdermal insulin delivery using choline-fatty acids ([Chl][FAs])-comprising three different FAs (C18:0, C18:1, and C18:2)-as biocompatible surface-active ILs (SAILs). The MEFs were successfully developed using [Chl][FAs] as surfactants, sorbitan monolaurate (Span-20) as a cosurfactant, choline propionate IL as an internal polar phase, and isopropyl myristate as a continuous oil phase. Ternary phase behavior, dynamic light scattering, and transmission electron microscopy studies revealed that MEFs were thermodynamically stable with nanoparticle size. The MEFs significantly enhanced the transdermal permeation of insulin via the intercellular route by compromising the tight lamellar structure of SC lipids through a fluidity-enhancing mechanism. In vivo transdermal administration of low insulin doses (50 IU/kg) to diabetic mice showed that MEFs reduced blood glucose levels (BGLs) significantly compared with a commercial surfactant-based formulation by increasing the bioavailability of insulin in the systemic circulation and sustained the insulin level for a much longer period (half-life > 24 h) than subcutaneous injection (half-life 1.32 h). When [Chl][C18:2] SAIL-based MEF was transdermally administered, it reduced the BGL by 56% of its initial value. The MEFs were biocompatible and nontoxic (cell viability > 90%). They remained stable at room temperature for 3 months and their biological activity was retained for 4 months at 4 °C. We believe SAIL-based MEFs will alter current approaches to insulin therapy and may be a potential transdermal nanocarrier for protein and peptide delivery.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Portadores de Fármacos/química , Emulsões/química , Insulina/administração & dosagem , Insulina/uso terapêutico , Líquidos Iônicos/química , Administração Cutânea , Animais , Colina/química , Ácidos Graxos/química , Feminino , Insulina/química , Insulina/farmacocinética , Camundongos Endogâmicos BALB C , Permeabilidade , Pele/metabolismo
11.
ACS Appl Bio Mater ; 4(8): 6256-6267, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35006923

RESUMO

Lipid-based biocompatible ionic liquids (LBILs) have attracted attention as carriers in transdermal drug delivery systems (TDDSs) because of their lipophilic character. In this study, we report the formulation of a peptide-LBIL complex microencapsulated in an oil phase as a potential carrier for the transdermal delivery of leuprolide acetate as a model hydrophilic peptide. The peptide-LBIL complexes were prepared via a water-in-oil emulsion composed of 1,2-dimyristoyl-sn-glycerol-3-ethyl-phosphatidylcholine (EDMPC), a fatty acid (stearic, oleic, and linoleic acid)-based LBIL, and cyclohexane followed by freeze-drying to remove the water and cyclohexane. Then, the peptide-LBIL complexes were nanodispersed and stabilized in isopropyl myristate (IPM) using sorbitol laurate (Span-20). Ionic-liquid-in-oil nanodispersions (IL/O-NDs) were prepared with varying weight ratios of LBILs and Span-20 as the surfactant and the cosurfactant, respectively. Keeping the overall surfactant constant at 10 wt % in IPM, a 5:5 wt % ratio of surfactant (IL) and cosurfactant (Span-20) in the IL/O-NDs significantly (p < 0.0001) increased the physiochemical stability, drug-loading capacity, and drug encapsulation efficiency. The in vitro and in vivo peptide delivery across the skin was increased significantly (p < 0.0001) using IL/O-NDs, compared with non-IL-treated groups. Of all of the LBIL-based formulations, [EDMPC][Linoleate]/O-ND was considered the most preferable for a TDDS based on the pharmacokinetic parameters. The transdermal delivery flux with [EDMPC][Linoleate]/O-ND was increased 65-fold compared with the aqueous delivery vehicle. The IL/O-NDs were able to deform the lipid and protein arrangements of the skin layers to enhance the transdermal permeation of the peptide. In vitro and in vivo cytotoxicity studies of the IL/O-NDs revealed the biocompatibility of the LBIL-based formulations. These results indicated that IL/O-NDs are promising biocompatible carriers for lipid-peptide TDDSs.


Assuntos
Líquidos Iônicos , Portadores de Fármacos/química , Líquidos Iônicos/química , Ácido Linoleico , Peptídeos , Absorção Cutânea , Tensoativos/química , Água
12.
Chem Commun (Camb) ; 56(89): 13756-13759, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33073787

RESUMO

We report a new series of lipid-based biocompatible ionic liquids (LBILs) consisting of the long-chain phosphonium compound 1,2-dimyristoyl-sn-glycero-3-ethyl-phosphatidylcholine as the cation and the long-chain fatty acids stearic acid, oleic acid, or linoleic acid as anions. These materials were found to be completely miscible with many polar and nonpolar organic solvents as well as dispersible in water. These LBILs also exhibited excellent biocompatibility with an artificial three-dimensional human epidermis model.


Assuntos
Materiais Biocompatíveis/química , Líquidos Iônicos/química , Lipídeos/química , Materiais Biocompatíveis/síntese química , Epiderme/química , Humanos , Líquidos Iônicos/síntese química , Estrutura Molecular , Solventes/síntese química , Solventes/química
13.
New Phytol ; 227(1): 132-145, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32129887

RESUMO

Photosynthetic stimulation by elevated [CO2 ] (e[CO2 ]) may be limited by the capacity of sink organs to use photosynthates. In many legumes, N2 -fixing symbionts in root nodules provide an additional sink, so that legumes may be better able to profit from e[CO2 ]. However, drought not only constrains photosynthesis but also the size and activity of sinks, and little is known about the interaction of e[CO2 ] and drought on carbon sink strength of nodules and other organs. To compare carbon sink strength, faba bean was grown under ambient (400 ppm) or elevated (700 ppm) atmospheric [CO2 ] and subjected to well-watered or drought treatments, and then exposed to 13 C pulse-labelling using custom-built chambers to track the fate of new photosynthates. Drought decreased 13 C uptake and nodule sink strength, and this effect was even greater under e[CO2 ], and was associated with an accumulation of amino acids in nodules. This resulted in decreased N2 fixation, and increased accumulation of new photosynthates (13 C/sugars) in leaves, which in turn can feed back on photosynthesis. Our study suggests that nodule C sink activity is key to avoid sink limitation in legumes under e[CO2 ], and legumes may only be able to achieve greater C gain if nodule activity is maintained.


Assuntos
Vicia faba , Dióxido de Carbono , Sequestro de Carbono , Fotossíntese , Abastecimento de Água
14.
J Plant Physiol ; 229: 164-169, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30103086

RESUMO

The 'CO2 fertilisation effect' is often predicted to be greater under drier than wetter conditions, mainly due to hypothesised early season water savings under elevated [CO2] (e[CO2]). However, water savings largely depend on the balance between CO2-induced improvement of leaf-level water use efficiency and CO2-stimulation of transpiring leaf area. The dynamics of water use during the growing season can therefore vary depending on leaf area development. Two canola (Brassica napus L.) cultivars of contrasting growth and vigour (vigorous hybrid cv. Hyola 50 and non-hybrid cv. Thumper) were grown under ambient [CO2] (a[CO2], ∼400 µmol mol-1) or e[CO2] (∼700 µmol mol-1) with two water treatments (well-watered and mild drought) in a glasshouse to investigate the interdependence of leaf area development and water use. Dynamics of water use during the growing season varied depending on [CO2] and cultivars. Early stimulation of leaf growth under e[CO2], which also depended on cultivar, overcompensated for the effect of increased leaf-level water use efficiency, so that weekly water use was greater and water depletion from soil greater under e[CO2] than a[CO2]. This result shows that the balance between leaf area and water use efficiency stimulation by e[CO2] can tip towards early depletion of available soil water, so that e[CO2] does not lead to water savings, and the 'CO2 fertilisation effect' is not greater under drier conditions.


Assuntos
Brassica napus/metabolismo , Dióxido de Carbono/metabolismo , Folhas de Planta/metabolismo , Água/metabolismo , Brassica napus/crescimento & desenvolvimento , Mudança Climática , Secas , Folhas de Planta/crescimento & desenvolvimento
15.
Plant Cell Environ ; 41(10): 2418-2434, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29859018

RESUMO

Increased biomass and yield of plants grown under elevated [CO2 ] often corresponds to decreased grain N concentration ([N]), diminishing nutritional quality of crops. Legumes through their symbiotic N2 fixation may be better able to maintain biomass [N] and grain [N] under elevated [CO2 ], provided N2 fixation is stimulated by elevated [CO2 ] in line with growth and yield. In Mediterranean-type agroecosystems, N2 fixation may be impaired by drought, and it is unclear whether elevated [CO2 ] stimulation of N2 fixation can overcome this impact in dry years. To address this question, we grew lentil under two [CO2 ] (ambient ~400 ppm and elevated ~550 ppm) levels in a free-air CO2 enrichment facility over two growing seasons sharply contrasting in rainfall. Elevated [CO2 ] stimulated N2 fixation through greater nodule number (+27%), mass (+18%), and specific fixation activity (+17%), and this stimulation was greater in the high than in the low rainfall/dry season. Elevated [CO2 ] depressed grain [N] (-4%) in the dry season. In contrast, grain [N] increased (+3%) in the high rainfall season under elevated [CO2 ], as a consequence of greater post-flowering N2 fixation. Our results suggest that the benefit for N2 fixation from elevated [CO2 ] is high as long as there is enough soil water to continue N2 fixation during grain filling.


Assuntos
Dióxido de Carbono/metabolismo , Lens (Planta)/metabolismo , Fixação de Nitrogênio , Biomassa , Produção Agrícola , Desidratação , Lens (Planta)/crescimento & desenvolvimento , Nitrogênio/metabolismo , Folhas de Planta/metabolismo , Nodulação , Água/metabolismo
16.
PLoS One ; 13(6): e0198928, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29902235

RESUMO

Through stimulation of root growth, increasing atmospheric CO2 concentration ([CO2]) may facilitate access of crops to sub-soil water, which could potentially prolong physiological activity in dryland environments, particularly because crops are more water use efficient under elevated [CO2] (e[CO2]). This study investigated the effect of drought in shallow soil versus sub-soil on agronomic and physiological responses of wheat to e[CO2] in a glasshouse experiment. Wheat (Triticum aestivum L. cv. Yitpi) was grown in split-columns with the top (0-30 cm) and bottom (31-60 cm; 'sub-soil') soil layer hydraulically separated by a wax-coated, root-penetrable layer under ambient [CO2] (a[CO2], ∼400 µmol mol-1) or e[CO2] (∼700 µmol mol-1) [CO2]. Drought was imposed from stem-elongation in either the top or bottom soil layer or both by withholding 33% of the irrigation, resulting in four water treatments (WW, WD, DW, DD; D = drought, W = well-watered, letters denote water treatment in top and bottom soil layer, respectively). Leaf gas exchange was measured weekly from stem-elongation until anthesis. Above-and belowground biomass, grain yield and yield components were evaluated at three developmental stages (stem-elongation, anthesis and maturity). Compared with a[CO2], net assimilation rate was higher and stomatal conductance was lower under e[CO2], resulting in greater intrinsic water use efficiency. Elevated [CO2] stimulated both above- and belowground biomass as well as grain yield, however, this stimulation was greater under well-watered (WW) than drought (DD) throughout the whole soil profile. Imposition of drought in either or both soil layers decreased aboveground biomass and grain yield under both [CO2] compared to the well-watered treatment. However, the greatest 'CO2 fertilisation effect' was observed when drought was imposed in the top soil layer only (DW), and this was associated with e[CO2]-stimulation of root growth especially in the well-watered bottom layer. We suggest that stimulation of belowground biomass under e[CO2] will allow better access to sub-soil water during grain filling period, when additional water is converted into additional yield with high efficiency in Mediterranean-type dryland agro-ecosystems. If sufficient water is available in the sub-soil, e[CO2] may help mitigating the effect of drying surface soil.


Assuntos
Dióxido de Carbono/farmacologia , Secas , Raízes de Plantas/crescimento & desenvolvimento , Solo/química , Triticum/efeitos dos fármacos , Triticum/crescimento & desenvolvimento , Água/análise , Atmosfera/química , Biomassa , Dióxido de Carbono/análise , Relação Dose-Resposta a Droga , Raízes de Plantas/efeitos dos fármacos
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