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1.
Disabil Rehabil ; : 1-11, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38095576

RESUMO

PURPOSE: To determine the effectiveness of interventions to increase physical activity (PA) in people with spinal cord injury (SCI). METHOD: Online databases PubMed, Medline, AMED and CINAHL were searched from the earliest date available to July 2022. Randomised controlled trials (RCT) exploring the effect of interventions on physical activity in people with SCI were eligible. The search identified 1191 studies, after screening 16 reports of 15 RCT's were included. Data were extracted on participant characteristics, intervention characteristics and physical activity outcomes. Methodological quality was assessed using the PEDro Scale and certainty of evidence assessed using GRADE. Post intervention means and standard deviations were pooled in meta-analyses to calculate standardised mean differences or mean differences and 95% confidence intervals. RESULTS: Fifteen trials with 693 participants (mean age 41-52) were included. There was moderate certainty evidence that exercise interventions had no effect on subjectively or objectively measured PA. There was moderate to high certainty evidence that behavioural interventions and combined behavioural and exercise interventions increased subjectively, but not objectively measured physical activity. CONCLUSION: Behaviour change techniques are an important intervention component for increasing PA in people with SCI.IMPLICATIONS FOR REHABILITATIONOnly half of people with spinal cord injury (SCI) meet physical activity guidelinesPhysical activity (PA) is important in managing primary and secondary complicationsExercise intervention alone does not increase PA in people with SCIInterventions should include behavioural techniques to increase PA in people with SCIInterventions that include behavioural techniques are shown to be effective across a wide range of SCI populations.

2.
Toxics ; 11(7)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37505533

RESUMO

Experimental spinach plants grown in soil with (5, 10 and 20 ppm) arsenic (As) contamination were sampled in 21 days after As(V) contamination. Levels of As in spinach samples (from 0.31 ± 0.06 µg g-1 to 302.69 ± 11.83 µg g-1) were higher in roots and lower in leaves, which indicates a low ability of spinach to translocate As into leaves. Species of arsenic, As(III) and As(V), were represented in favor of the As (III) specie in contaminated variants, suggesting enzymatic arsenate reduction. In relation to predominant As accumulation in roots, changes in malondialdehyde levels were observed mainly in roots, where they decreased significantly with growing As contamination (from 11.97 ± 0.54 µg g-1 in control to 2.35 ± 0.43 µg g-1 in 20 ppm As). Higher values in roots than in leaves were observed in the case of 5-methylcytosine (5-mC). Despite that, a change in 5-mC by As contamination was further deepened in leaves (from 0.20 to 14.10%). In roots of spinach, expression of the CDC25 gene increased by the highest As contamination compared to the control. In the case of total phenolic content, total flavonoid content, total phenolic acids content and total antioxidant capacity were higher levels in leaves in all values, unlike the roots.

3.
Toxics ; 11(3)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36977002

RESUMO

Arsenic represents a serious health threat in localities with a high arsenic-polluted environment and can easily get into the human food chain through agronomy production in areas affected by arsenic contamination. Onion plants that were grown in controlled conditions in arsenic-contaminated soil (5, 10, and 20 ppm) were harvested 21 days after contamination. Arsenic levels (from 0.43 ± 0.03 µg g-1 to 1761.11 ± 101.84 µg g-1) in the onion samples were high in the roots and low in the bulbs and leaves, which is probably caused by a reduced ability of the onions to transport arsenic from roots to bulbs and leaves. Arsenic species As(V) and As(III) in As(V)-contaminated soil samples were represented strongly in favor of the As(III) species. This indicates the presence of arsenate reductase. Levels of 5-methylcytosine (5-mC) (from 5.41 ± 0.28% to 21.17 ± 1.33%) in the onion samples were also higher in the roots than in the bulbs and leaves. Microscopic sections of the roots were examined, and the most damage was found in the 10 ppm As variant. Photosynthetic parameters pointed to a significant decrease in photosynthetic apparatus activity and the deterioration of the physiological state of plants as arsenic content increased in the soil.

4.
PLoS One ; 17(4): e0260746, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35381013

RESUMO

Climatic conditions play a significant role in the development of citrus canker caused by Xanthomonas citri pv. citri (Xcc). Citrus canker is regarded as one of the major threats being faced by citrus industry in citrus growing countries of the world. Climatic factors exert significant impacts on growth stage, host susceptibility, succulence, vigor, survival, multiplication rate, pathogen dispersion, spore penetration rate, and spore germination. Predicting the impacts of climatic factors on these traits could aid in the development of effective management strategies against the disease. This study predicted the impacts of environmental variables, i.e., temperature, relative humidity, rainfall, and wind speed the development of citrus canker through multiple regression. These environmental variables were correlated with the development of canker on thirty (30) citrus varieties during 2017 to 2020. Significant positive correlations were noted among environment variables and disease development modeled through multiple regression model (Y = +24.02 + 0.5585 X1 + 0.2997 X2 + 0.3534 X3 + 3.590 X4 + 1.639 X5). Goodness of fit of the model was signified by coefficient determination value (97.5%). Results revealed the optimum values of environmental variables, i.e., maximum temperature (37°C), minimum temperature (27°C), relative humidity (55%), rainfall (4.7-7.1 mm) and wind speed (8 Km/h), which were conducive for the development of citrus canker. Current study would help researchers in designing better management strategies against citrus canker disease under changing climatic conditions in the future.


Assuntos
Citrus , Xanthomonas , Doenças das Plantas
5.
PLoS One ; 17(1): e0262586, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35085310

RESUMO

Synthetic fertilizer and herbicides encompass the largest share in nutrient and weed management on food grain crops that create serious environmental issues. Integrated nutrient and non-chemical weed management approaches may help to reduce the chemical load in the environment, maintaining higher weed control efficiency and yield. A field experiment was conducted for two consecutive monsoon seasons during 2015 and 2016 in farm fields to develop a profitable and sustainable rice production system through integrated nutrient and weed management practices. A varied combination of nutrients either alone or integrated with chemical and non-chemical weed management were tested on transplanted rice in a factorial randomized block design with three replications. The results showed that the integration of concentrated organic manures with chemical fertilizer effectively inhibited weed growth and nutrient removal. Integration of nutrient and weed management practices significantly enhanced 9% biomass growth, 10% yield of the rice crop along with 3-7% higher nutrient uptake. Brassicaceous seed meal (BSM) and neem cake also had some influence on weed suppression and economic return. Thus, the integrated nutrient and weed management practices in rice cultivation might be an effective way to achieve economic sustainability and efficient rice cultivation in eastern India. Shortages of farmyard manure and vermicompost could be supplemented by BSM and neem cake in the integrated module.


Assuntos
Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/crescimento & desenvolvimento , Solo/química , Agricultura/métodos , Biomassa , Carbono/química , Produtos Agrícolas/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Fertilizantes , Herbicidas/farmacologia , Índia , Esterco , Nitrogênio/química , Nutrientes/química , Fósforo/química , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento
6.
J Fungi (Basel) ; 7(12)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34947042

RESUMO

Rice blast is considered one of the most important fungal diseases of rice. Although diseases can be managed by using resistant cultivars, the blast pathogen has successfully overcome the single gene resistance in a short period and rendered several varieties susceptible to blast which were otherwise intended to be resistant. As such, chemical control is still the most efficient method of disease control for reducing the losses caused due to diseases. Field experiments were conducted over two successive years, 2018 and 2019, in temperate rice growing areas in northern India. All the fungicides effectively reduced leaf blast incidence and intensity, and neck blast incidence under field conditions. Tricyclazole proved most effective against rice blast and recorded a leaf blast incidence of only 8.41%. Among the combinations of fungicides, azoxystrobin + difenoconazole and azoxystrobin + tebuconazole were highly effective, recording a leaf blast incidence of 9.19 and 10.40%, respectively. The chemical combination mancozeb + carbendazim proved less effective in controlling the blast and it recorded a disease incidence of 27.61%. A similar trend was followed in neck blast incidence with tricyclazole, azoxystrobin + difenoconazole, and azoxystrobin + tebuconazole showing the highest levels of blast reductions. It is evident from the current study that the tested fungicide combinations can be used as alternatives to tricyclazole which is facing the challenges of fungicide resistance development and other environmental concerns and has been banned from use in India and other countries. The manuscript may provide a guideline of fungicide application to farmers cultivating susceptible varieties of rice.

7.
Front Plant Sci ; 12: 670369, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34484254

RESUMO

In the era of rapid climate change, abiotic stresses are the primary cause for yield gap in major agricultural crops. Among them, salinity is considered a calamitous stress due to its global distribution and consequences. Salinity affects plant processes and growth by imposing osmotic stress and destroys ionic and redox signaling. It also affects phytohormone homeostasis, which leads to oxidative stress and eventually imbalances metabolic activity. In this situation, signaling compound crosstalk such as gasotransmitters [nitric oxide (NO), hydrogen sulfide (H2S), hydrogen peroxide (H2O2), calcium (Ca), reactive oxygen species (ROS)] and plant growth regulators (auxin, ethylene, abscisic acid, and salicylic acid) have a decisive role in regulating plant stress signaling and administer unfavorable circumstances including salinity stress. Moreover, recent significant progress in omics techniques (transcriptomics, genomics, proteomics, and metabolomics) have helped to reinforce the deep understanding of molecular insight in multiple stress tolerance. Currently, there is very little information on gasotransmitters and plant growth regulator crosstalk and inadequacy of information regarding the integration of multi-omics technology during salinity stress. Therefore, there is an urgent need to understand the crucial cell signaling crosstalk mechanisms and integrative multi-omics techniques to provide a more direct approach for salinity stress tolerance. To address the above-mentioned words, this review covers the common mechanisms of signaling compounds and role of different signaling crosstalk under salinity stress tolerance. Thereafter, we mention the integration of different omics technology and compile recent information with respect to salinity stress tolerance.

8.
Molecules ; 26(12)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207649

RESUMO

Micronutrient malnutrition is a global health issue and needs immediate attention. Over two billion people across the globe suffer from micronutrient malnutrition. The widespread zinc (Zn) deficiency in soils, poor zinc intake by humans in their diet, low bioavailability, and health consequences has led the research community to think of an economic as well as sustainable strategy for the alleviation of zinc deficiency. Strategies like fortification and diet supplements, though effective, are not economical and most people in low-income countries cannot afford them, and they are the most vulnerable to Zn deficiency. In this regard, the biofortification of staple food crops with Zn has been considered a useful strategy. An agronomic biofortification approach that uses crop fertilization with Zn-based fertilizers at the appropriate time to ensure grain Zn enrichment has been found to be cost-effective, easy to practice, and efficient. Genetic biofortification, though time-consuming, is also highly effective. Moreover, a Zn-rich genotype once developed can also be used for many years without any recurring cost. Hence, both agronomic and genetic biofortification can be a very useful tool in alleviating Zn deficiency.


Assuntos
Biofortificação/métodos , Produtos Agrícolas/genética , Fertilizantes/análise , Alimentos Fortificados/normas , Desnutrição/dietoterapia , Solo/química , Zinco/química , Humanos , Desnutrição/fisiopatologia , Estado Nutricional
9.
Genes (Basel) ; 12(6)2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34073848

RESUMO

Genome-editing (GE) is having a tremendous influence around the globe in the life science community. Among its versatile uses, the desired modifications of genes, and more importantly the transgene (DNA)-free approach to develop genetically modified organism (GMO), are of special interest. The recent and rapid developments in genome-editing technology have given rise to hopes to achieve global food security in a sustainable manner. We here discuss recent developments in CRISPR-based genome-editing tools for crop improvement concerning adaptation, opportunities, and challenges. Some of the notable advances highlighted here include the development of transgene (DNA)-free genome plants, the availability of compatible nucleases, and the development of safe and effective CRISPR delivery vehicles for plant genome editing, multi-gene targeting and complex genome editing, base editing and prime editing to achieve more complex genetic engineering. Additionally, new avenues that facilitate fine-tuning plant gene regulation have also been addressed. In spite of the tremendous potential of CRISPR and other gene editing tools, major challenges remain. Some of the challenges are related to the practical advances required for the efficient delivery of CRISPR reagents and for precision genome editing, while others come from government policies and public acceptance. This review will therefore be helpful to gain insights into technological advances, its applications, and future challenges for crop improvement.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes/métodos , Melhoramento Vegetal/métodos , Genoma de Planta
10.
Molecules ; 26(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070241

RESUMO

Lipoic acid (LA) and melatonin (MT) are pleiotropic molecules participating in plant stress resistance by modulating cellular biochemical changes, ion homeostasis, and antioxidant enzyme activities. However, the combined role of these two molecules in counteracting the detrimental impacts of salinity stress is still unknown. In the present study, we determined the effects of exogenous LA (0.5 µM), MT (1 µM) and their combination (LA + MT) on growth performance and biomass accumulation, photosynthetic pigments, enzymatic and non-enzymatic antioxidant activities, and ions homeostatic in canola (Brassica napus L.) seedlings under salinity stress (0, 100 mM) for 40 days. The results indicate that exogenous application of LA + MT improved the phenotypic growth (by 25 to 45%), root thickness (by 68%), number of later lateral roots (by 52%), root viability (by 44%), and root length (by 50%) under salinity stress. Moreover, total soluble protein, chlorophyll pigments, the concentration of superoxide dismutase (SOD), catalase peroxidase (CAT), and ascorbic peroxidase (ASA) increased with the presence of salt concentration into the growth media and then decreased with the addition of LA + MT to saline solution. Leaf protein contents and the degradation of photosynthetic pigments were lower when LA + MT treatments were added into NaCl media. The proline and phenol contents decreased in the exogenous application of LA + MT treatments more than individual LA or MT treatments under the salinity stress. The incorporation of LA or MT or a combination of LA + MT to saline solution decreased salinity-induced malondialdehyde and electrolyte leakage. In conclusion, the alteration of metabolic pathways, redox modulation, and ions homeostasis in plant tissues by the combined LA and MT application are helpful towards the adaptation of Brassica napus L. seedlings in a saline environment. The results of this study provide, for the first time, conclusive evidence about the protective role of exogenous LA + MT in canola seedlings under salinity stress.


Assuntos
Brassica napus/crescimento & desenvolvimento , Produtos Agrícolas/crescimento & desenvolvimento , Melatonina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Estresse Salino , Ácido Tióctico/farmacologia , Antioxidantes/metabolismo , Biomassa , Brassica napus/metabolismo , Produtos Agrícolas/metabolismo , Homeostase , Malondialdeído/metabolismo , Minerais/metabolismo , Fenóis/metabolismo , Fotossíntese/efeitos dos fármacos , Pigmentos Biológicos/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento
11.
Plants (Basel) ; 10(5)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33922210

RESUMO

In this investigation, the effect of salt stress on Portulaca oleracea L. was monitored at salinity levels of 100 and 300 mM NaCl. At a concentration of 100 mM NaCl there was a decrease in stomatal conductance (gs) simultaneously with an increase in CO2 assimilation (A) at the beginning of salt exposure (day 3). However, the leaf water potential (ψw), the substomatal concentration of CO2 (Ci), the maximum quantum yield of photosystem II (Fv/Fm), and the proline and malondialdehyde (MDA) content remained unchanged. Exposure to 300 mM NaCl caused a decrease in gs from day 3 and a decrease in water potential, CO2 assimilation, and Fv/Fm from day 9. There was a large increase in proline content and a significantly higher MDA concentration on days 6 and 9 of salt stress compared to the control group. After 22 days of exposure to 300 mM NaCl, there was a transition from the C4 cycle to crassulacean acid metabolism (CAM), manifested by a rapid increase in substomatal CO2 concentration and negative CO2 assimilation values. These results document the tolerance of P. oleracea to a lower level of salt stress and the possibility of its use in saline localities.

12.
Nanomaterials (Basel) ; 11(3)2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33801046

RESUMO

A novel antimicrobial formulation based on carboxymethylcellulose (CMC) spray-coated Cu2+ intercalated montmorillonite (MMT) nanocomposite material was prepared and its morphology, internal structure, and bonding interactions were studied. Meanwhile, the antibacterial efficacy and release behavior of Cu2+ was also determined. PXRD patterns indicated the intercalation of Cu2+, while FTIR spectra and TGA traces confirmed the association of Cu-MMT with CMC. SEM study revealed the improvement of nanocomposites by CMC, without disturbing the clay structure. TEM and EDAX studies indicated the distribution of Cu (copper) throughout the composite. In vitro antibacterial assays performed with Erwinia carotovora revealed effective bacterial growth suppression, indicating the potential of this material in controlling soft rot of potatoes (Solanum tuberosum); also observed was a connection between growth inhibition and concentration of CMC spray coats indicating a positive relationship between Cu2+ release and concentration of the CMC coatings. The activity pattern of the nanocomposite displayed a significant degree of sustained-release behavior.

13.
Nanomaterials (Basel) ; 11(3)2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33803416

RESUMO

Salt stress severely reduces growth and yield of plants. Considering the positive effects of selenium (Se) and chitosan (Cs) separately against abiotic stress, in these experiments, we synthesized chitosan-selenium nanoparticles (Cs-Se NPs) and investigated their ability to reduce the negative effects of salt stress on growth and some biochemical parameters of bitter melon (Momordica charantia). Bitter melon plants were grown at three NaCl salinity levels (0, 50, and 100 mM) and a foliar spray of Cs-Se NPs (0, 10, and 20 mg L-1) was applied. Some key morphological, biochemical, and physiological parameters in leaf samples and essential oil from fruit were measured at harvest. Salinity decreased growth and yield while foliar application of Cs-Se NPs increased these critical parameters. Furthermore, Cs-Se NPs enhanced bitter melon tolerance to salinity by increasing antioxidant enzyme activity, proline concentration, relative water content, and K+, and decreasing MDA and H2O2 oxidants and Na aggregation in plant tissues. Yield was also improved, as the highest amount of essential oils was produced by plants treated with Cs-Se NPs. Generally, the greatest improvement in measured parameters under saline conditions was obtained by treating plants with 20 mg L-1 Cs-Se NPs, which significantly increased salinity tolerance in bitter melon plants.

14.
Plants (Basel) ; 9(12)2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33316881

RESUMO

The goal of this study was to determine whether the application of gibberellic acid (GA3) to seeds of common wheat varieties with different vernalization and photoperiod requirements affects the transition from vegetative to generative stage. Three varieties of wheat with different photoperiod sensitivities and vernalization were selected for the experiment-the winter varieties, Mironovskaya and Bezostaya, and the spring variety, Sirael. Seeds were treated with different concentrations of GA3 and plants were grown under long-day conditions with monitoring of their photosynthetic activity (Fv/Fm, Pn, E, gs). We monitored the activity of the photosynthetic apparatus by checking the plants to see if they were growing properly. The phenological stages of the wheat species were checked for indications of a transition from the vegetative to the generative stage. Selected concentrations of GA3 had no effect on the compensation of the vernalization process (transition to the generative phase). Chlorophyll fluorescence was one of the factors for monitoring stress. The variety, Bezostaya, is similar to the spring variety, Sirael, in its trends and values. The growth conditions of Bezostaya and Sirael were not affected by the activity of the photosynthetic apparatus. The development of growing points in winter varieties occurred at the prolonged single ridge stage. The spring variety reached the stage of head emergence after sixty days of growth (changes to the flowering phase did not appear in winter wheat). Application of GA3 to the seeds had no effect on the transition of the growing point to the double-ridge generative stage. The present study highlights the priming effect of GA3 on seeds of common wheat varieties with different vernalization and photoperiod requirements as it affected the transition from vegetative to generative stage.

15.
Life (Basel) ; 10(11)2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33238445

RESUMO

This study analyzes the effects of acetaminophen (APAP) as a contaminant on physiological characteristics of lettuce plants (Lactuca sativa L.). Experiments were provided in an experimental greenhouse with semi-controlled conditions. The effect of different amounts of contaminant was evaluated by using regression analysis. Plants were grown in five concentrations of APAP: 0 µM, 5 µM, 50 µM, 500 µM, and 5 mM for 14 days in two variants, acute and chronic. The obtained results show that the monitored parameters were demonstrably influenced by the experimental variant. Plants are more sensitive to chronic contamination compared to acute. Significant (p < 0.05) deviation in photosynthesis and fluorescence was observed compared to the control in different variants. The highest doses of APAP reduced the intensity of photosynthesis by a maximum of more than 31% compared to the control. A reduction of 18% was observed for the fluorescence parameters. Pronounced correlation was described between chlorophyll fluorescence parameters and yield mainly under APAP conditions. The amount of chlorophyll was influenced by exposure to APAP.

16.
Molecules ; 25(22)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33218115

RESUMO

There are 11 different varieties of Beta vulgaris L. that are used in the food industry, including sugar beets, beetroots, Swiss chard, and fodder beets. The typical red coloration of their tissues is caused by the indole-derived glycosides known as betalains that were analyzed in hypocotyl extracts by UV/Vis spectrophotometry to determine the content of betacyanins (betanin) and of betaxanthins (vulgaxanthin I) as constituents of the total betalain content. Fields of beet crops use to be also infested by wild beets, hybrids related to B. vulgaris subsp. maritima or B. macrocarpa Guss., which significantly decrease the quality and quantity of sugar beet yield; additionally, these plants produce betalains at an early stage. All tested B. vulgaris varieties could be distinguished from weed beets according to betacyanins, betaxanthins or total betalain content. The highest values of betacyanins were found in beetroots 'Monorubra' (9.69 mg/100 mL) and 'Libero' (8.42 mg/100 mL). Other beet varieties contained less betacyanins: Sugar beet 'Labonita' 0.11 mg/100 mL; Swiss chard 'Lucullus,' 0.09 mg/100 mL; fodder beet 'Monro' 0.15 mg/100 mL. In contrast with weed beets and beetroots, these varieties have a ratio of betacyanins to betaxanthins under 1.0, but the betaxanthin content was higher in beetcrops than in wild beet and can be used as an alternative to non-red varieties. Stability tests of selected varieties showed that storage at 22 °C for 6 h, or at 7 °C for 24 h, did not significantly reduce the betalain content in the samples.


Assuntos
Beta vulgaris/química , Betacianinas/análise , Betaxantinas/análise , Plantas Daninhas/química , Beta vulgaris/genética , Betacianinas/química , Betalaínas/análise , Genótipo , Hipocótilo/química , Extratos Vegetais/química
17.
Plants (Basel) ; 9(4)2020 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-32325817

RESUMO

Salt stress is one of the most serious environmental stressors that affect productivity of salt-sensitive crops. Medicago ciliaris is an annual legume whose adaptation to agroclimatic conditions has not been well described. This study focused on the salinity tolerance of M. ciliaris genotypes compared to M. intertexta and M. scutellata in terms of plant growth, physiology, and biochemistry. Salt tolerance was determined at both germination and early seedling growth. Germination and hydroponic assays were used with exposing seeds to 0, 50, 100, 150, and 200 mM NaCl. Among seven genotypes of M. ciliaris studied, Pop1, 355, and 667, were most salt tolerant. Populations like 355 and 667 showed marked tolerance to salinity at both germination and seedling stages (TI ≤1, SI(FGP) > 0 increased FGP ≥ 20% and SI(DW) < 0 (DW decline ≤ 20%); at 100 mM); while Pop1 was the most salt tolerant one at seedling stages with (TI =1.79, SI(FGP) < 0 decline of FGP ≤ 40% and with increased DW to 79%); at 150 mM NaCl). The genotypes, 306, 773, and M. scutellata, were moderately tolerant to salt stress depending on salt concentration. Our study may be used as an efficient strategy to reveal genetic variation in response to salt stress. This approach allows selection for desirable traits, enabling more efficient applications in breeding methods to achieve stress-tolerant M. ciliaris populations.

18.
Molecules ; 24(14)2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31323864

RESUMO

Crops, such as white cabbage (Brassica oleracea L. var. capitata (L.) f. alba), are often infested by herbivorous insects that consume the leaves directly or lay eggs with subsequent injury by caterpillars. The plants can produce various defensive metabolites or free radicals that repel the insects to avert further damage. To study the production and effects of these compounds, large white cabbage butterflies, Pieris brassicae and flea beetles, Phyllotreta nemorum, were captured in a cabbage field and applied to plants cultivated in the lab. After insect infestation, leaves were collected and UV/Vis spectrophotometry and HPLC used to determine the content of stress molecules (superoxide), primary metabolites (amino acids), and secondary metabolites (phenolic acids and flavonoids). The highest level of superoxide was measured in plants exposed to fifty flea beetles. These plants also manifested a higher content of phenylalanine, a substrate for the synthesis of phenolic compounds, and in activation of total phenolics and flavonoid production. The levels of specific phenolic acids and flavonoids had higher variability when the dominant increase was in the flavonoid, quercetin. The leaves after flea beetle attack also showed an increase in ascorbic acid which is an important nutrient of cabbage.


Assuntos
Ácido Ascórbico/química , Brassica/química , Brassica/parasitologia , Ectoparasitoses , Extratos Vegetais/química , Folhas de Planta/química , Polifenóis/química , Redes e Vias Metabólicas , Estrutura Molecular
19.
J Environ Manage ; 205: 50-58, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28964974

RESUMO

Geodiversity plays an important role in species establishment during spontaneous succession. At post-mining sites in the Czech Republic in 2003, we established plots in which the surface of the heaped overburden was either kept wave-like or leveled. Based on surveys conducted from 2006 to 2015, leveled plots were increasingly dominated by grasses and herbs (and especially by the grass Calamagrostis epigejos) while the wave-like plots were increasingly dominated by the trees Salix caprea and Betula pendula. In 2015, a detailed survey was conducted of the dominant species. Both S. caprea and B. pendula occurred more often in wave-like plots than in leveled plots; this was particularly true for trees taller than 1 m, which were absent in leveled plots. In wave-like plots, leaf and root biomasses of both woody species were higher on the wave slopes than on the wave depressions. Nitrogen content was higher but content stress indicating proline in leaves of S. caprea was lower in wave-like plots than in leveled plots. In wave-like plots, both woody species occurred mainly on wave slopes but C. epigejos occurred mainly in the depressions. We speculate that trees were more abundant in wave-like plots than in leveled plots because the waves trapped tree seeds and snow and because the soil porosity was greater in wave-like than in leveled plots. Grasses may have preferred the leveled plots because soil porosity was lower and clay content was higher in leveled than in wave-like plots.


Assuntos
Meio Ambiente , Poaceae , República Tcheca , Solo , Árvores , Madeira
20.
Environ Pollut ; 229: 94-101, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28582678

RESUMO

We propose a method for monitoring heavy metal deposition in the vicinity of roads using the leaf surfaces of two expansive grass species which are greatly abundant. A principle of the proposed procedure is to minimize the number of operations in collecting and preparing samples for analysis. The monitored elements are extracted from the leaf surfaces using dilute nitric acid directly in the sample-collection bottle. The ensuing steps, then, are only to filter the extraction solution and the elemental analysis itself. The verification results indicate that the selected grasses Calamagrostis epigejos and Arrhenatherum elatius are well suited to the proposed procedure. Selected heavy metals (Zn, Cu, Pb, Ni, Cr, and Cd) in concentrations appropriate for direct determination using methods of elemental analysis can be extracted from the surface of leaves of these species collected in the vicinity of roads with medium traffic loads. Comparing the two species showed that each had a different relationship between the amounts of deposited heavy metals and distance from the road. This disparity can be explained by specific morphological properties of the two species' leaf surfaces. Due to the abundant occurrence of the two species and the method's general simplicity and ready availability, we regard the proposed approach to constitute a broadly usable and repeatable one for producing reproducible results.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Metais Pesados/análise , Poaceae/química , Poluição Ambiental/análise , Poluição Ambiental/estatística & dados numéricos , Meios de Transporte
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