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1.
Org Lett ; 26(16): 3361-3365, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38625171

RESUMEN

We developed an efficient and environmentally friendly methodology for selectively synthesizing highly substituted phenols using readily available enallenoates and Grignard reagents. This method consistently yields good to excellent results across over 60 examples, demonstrating the substrate scope and the exploration of phenol product derivatization, further extending the method's utility.

2.
Econ Hum Biol ; 53: 101373, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38531263

RESUMEN

This paper examines the relationship between a national unconditional cash transfers (UCTs) program, health and savings. We theoretically and empirically show that motives to save can be strong when cash transfers promote health outcomes. We first present a theoretical model that considers lifecycle-consumption savings decisions, where households derive utility from consumption and leisure time at working age, as well as old-age consumption and old-age longevity that positively depend on health spending. We then empirically examine the impact of Pakistan's Benazir Income Support Programme on various indicators of savings and provide suggestive evidence on how UCTs influence savings via health. We find that in the short and medium term, UCTs increase the probability that a household decides to save and have significant positive effects on the rates and amounts of household savings. The effects of UCTs are more pronounced on informal compared to formal savings. The results present exploratory and suggestive evidence that health is a mechanism through which UCTs transmit to savings. These findings are consistent with our theoretical predictions.


Asunto(s)
Estado de Salud , Humanos , Pakistán , Gastos en Salud/estadística & datos numéricos , Composición Familiar , Motivación
3.
Org Lett ; 26(12): 2430-2434, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38502799

RESUMEN

A highly efficient dehydrogenative carbonylative esterification of allenoic acids using Pd-catalysis was developed, providing a novel approach to synthesizing esterified γ-butyrolactone derivatives with consistently good to excellent results demonstrated across over 50 examples. Additionally, we used a heterogeneous catalyst known as Pd-AmP-MCF and harnessed biomimetic-aerobic-oxidation conditions to facilitate the practical execution of this reaction. Furthermore, our detailed study of γ-butyrolactone products highlighted their potential in synthesizing bioactive compounds.

4.
J Biomol Struct Dyn ; 41(19): 9232-9244, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37897194

RESUMEN

Microbial resistance to drugs currently traded in the market is a serious problem in modern medicine. In this field of research, we synthesized a novel N-acylsulfonamides (NAS) derivatives starting from commercially available compounds; morpholine, isocyanate of chlorosulfonyl and alcohols. The in vitro antimicrobial potential of synthesized compounds was screened against 04 Gram-negative bacteria; Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumannii, 02 Gram-positive bacteria: Streptococcus sp, Staphylococcus aureus and 07 yeasts and fungi: Candida albicans, Candida spp, Penicillum spp, Aspegillus sp, Aspergillus flavus, Fusarium sp, and Cladosporium spp. The results of inhibition growth were compared with standard antimicrobial drugs with the goal of exploring their potential antimicrobial activity. In addition, the anti-inflammatory activity of the synthesized compounds was determined in-vitro by protein denaturation method. The obtained bioactivity results were further validated by in silico DFT (Density Functional Theory), ADME (Absorption-Distribution-Métabolisation-Excrétion), molecular docking studies and molecular dynamics simulations.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Antiinfecciosos , Simulación de Dinámica Molecular , Simulación del Acoplamiento Molecular , Pruebas de Sensibilidad Microbiana , Antiinfecciosos/farmacología , Antiinflamatorios/farmacología , Antibacterianos/farmacología
5.
BJPsych Int ; 20(3): 54-56, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37531228

RESUMEN

This report is based on the extrapolation to 2020 of data on the economic burden of mental illnesses in Pakistan in 2006. Given the resultant estimated high economic burden of mental illness in the country (£2.97 billion in 2020), we advocate a revised budget allocation to mental healthcare. As a resource-scarce nation that is entangled in natural disasters, Pakistan needs cost-effective psychological interventions such as culturally adapted manual-assisted problem-solving training (C-MAP) for the prevention of self-harm and suicide and to move towards attaining the United Nations' Sustainable Development Goals (SDGs). Although government has taken initiatives to support healthcare services (such as the Sehat Sahulat Program for universal health coverage), there is still a need to implement a cost-effective national digital model for mental healthcare such as the Agha Khan Development Network Digital Health Programme.

6.
Cureus ; 14(9): e28683, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36199645

RESUMEN

Background and aims Peripheral neuropathy is a frequent complication of long-standing diabetes mellitus that adversely affects the quality of life. Pregabalin (anticonvulsant) and duloxetine (antidepressant) are often prescribed for diabetic peripheral neuropathic pain. This study aimed to determine and compare the efficacy and safety of pregabalin and duloxetine in patients with diabetic peripheral neuropathic pain. Materials and methods This prospective observational study was conducted at District Headquarter (DHQ) Hospital, Daggar, Buner district, Pakistan, from February 15 to July 15, 2022, after approval from the Institutional Research and Ethical Review Board. Confirmation of diabetic peripheral neuropathy was based on the history of diabetes mellitus and vibration perception threshold (VPT) using a biothesiometer. The cut-off was set at 15 volts. VPT of more than 15 volts was considered confirmatory for peripheral neuropathy. Patients were divided equally into two groups. Baseline visual analog scale (VAS) score was recorded for all patients. Tablet pregabalin 300 mg daily was administered for four weeks to one group, while tablet duloxetine in 60 mg strength daily was administered to the other group. VAS score after four-week treatment was recorded and compared. Adverse events experienced by the patient were also noted. Results A total of 86 patients were enrolled. The patient ages ranged from 30 to 80 years. Baseline characteristics, including mean age, mean BMI, and mean disease duration of duloxetine versus pregabalin group, were 50.30 ± 8.55 versus 48.20 ± 8.99 years, 23.47 ± 1.23 versus 23.10 ± 1.59 kg/m2 and 21.64 ±7.41 versus 20.04±6.37 months respectively. Duloxetine effectively controlled peripheral neuropathic pain in 81.4% of patients compared to pregabalin in 74.4% of patients. Severe drug-related adverse reactions were observed in 4.6% of patients with duloxetine compared to 0% with pregabalin. Conclusion Duloxetine and pregabalin effectively reduce diabetes-related peripheral neuropathic pain. However, duloxetine has slightly better outcomes than pregabalin. The safety profile of pregabalin is better than duloxetine.

7.
Value Health Reg Issues ; 27: 65-71, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34844061

RESUMEN

OBJECTIVES: Self-harm is a serious public health problem. A culturally adapted manual-assisted problem-solving training (C-MAP) intervention improved and sustained a reduction in suicidal ideation, hopelessness, and depression compared with treatment as usual (TAU) alone. Here, we evaluate its cost-effectiveness. METHODS: Patients admitted after an episode of self-harm were randomized individually to either C-MAP plus TAU or TAU alone in Karachi. Improvement in health-related quality-adjusted life-years (QALYs) was measured using the EQ-5D with 3 levels instrument at baseline, 3 months, and 6 months after randomization. The primary economic outcome was health service cost per QALY gained as the incremental cost-effectiveness ratio, based on 2019 US$ and a 6-month time horizon. Nonparametric bootstrapping was used to assess uncertainties and sensitivity analysis to examine the impact of hospitalization costs. RESULTS: A total of 108 and 113 participants were enrolled among the intervention and standard arms, respectively. The intervention resulted in 0.04 (95% confidence interval [CI] 0.00-0.08) more QALYs 6 months after enrolment. The mean cost per participant in the intervention arm was $1001 (95% CI 968-1031), resulting in an incremental cost of the intervention of $640 (95% CI 595-679). The incremental cost-effectiveness ratio for the C-MAP intervention versus TAU was $16 254 (95% CI 7116-99 057) per QALY gained. The probability that C-MAP is cost-effective was between 66% and 83% for cost-effective thresholds between $20 000 and $30 000. Cost-effectiveness results remained robust to sensitivity analyses. CONCLUSIONS: C-MAP may be a valuable self-harm intervention. Further studies with longer follow-up and larger sample sizes are needed to draw reliable conclusions.


Asunto(s)
Intervención Psicosocial , Conducta Autodestructiva , Análisis Costo-Beneficio , Humanos , Pakistán , Años de Vida Ajustados por Calidad de Vida
8.
Front Plant Sci ; 12: 743618, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34858450

RESUMEN

Phosphorus (P) is an essential macronutrient needed for plant growth, development, and production. A deficiency of P causes a severe impact on plant development and productivity. Several P-based fertilizers are being used in agriculture but limited uptake of P by the plant is still a challenge to be solved. Titanium (Ti) application increases the nutrient uptake by affecting the root growth; however, the role of Ti in plant biology, specifically its application under low light and phosphorus stress, has never been reported. Therefore, a pot study was planned with foliar application of Ti (in a different concentration ranging from 0 to 1,000 mg L-1) under different light and P concentrations. The result indicated that under shade and low P conditions the foliar application of Ti in different concentrations significantly improves the plant growth parameters such as root length, root surface area, root dry matter, and shoot dry matters. The increase was observed to be more than 100% in shade and low P stressed soybean root parameter with 500 mg L-1 of Ti treatment. Ti was observed to improve the plant growth both in high P and low P exposed plants, but the improvement was more obvious in Low P exposed plants. Auxin concentration in stressed and healthy plant roots was observed to be slightly increased with Ti application. Ti application was also observed to decrease rhizosphere soil pH and boosted the antioxidant enzymatic activities with an enhancement in photosynthetic efficiency of soybean plants under shade and P stress. With 500 mg L-1 of Ti treatment, the photosynthetic rate was observed to improve by 45% under shade and P stressed soybean plants. Thus, this work for the first time indicates a good potential of Ti application in the low light and P deficient agricultural fields for the purpose to improve plant growth and development parameters.

9.
Value Health Reg Issues ; 25: 150-156, 2021 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-34198122

RESUMEN

OBJECTIVES: Self-harm is a serious public health problem. A culturally adapted manual-assisted problem-solving training (C-MAP) intervention improved and sustained the reduction in suicidal ideation, hopelessness, and depression compared with treatment as usual (TAU) alone. Here, we evaluate its cost-effectiveness. METHODS: Patients admitted after an episode of self-harm were randomized individually to either C-MAP plus TAU or TAU alone in Karachi. Improvement in health-related quality-adjusted life years (QALYs) was measured using the Euro Qol-5D-3L instrument at baseline and at 3 months and 6 months after randomization. The primary economic outcome was health service cost per QALY gained as the incremental cost-effectiveness ratio, based on 2019 US dollars and a 6-month time horizon. Nonparametric bootstrapping was used to assess uncertainties, and sensitivity analysis to examine the impact of hospitalization costs. RESULTS: A total of 108 and 113 participants were enrolled among the intervention and standard arms, respectively. The intervention resulted in 0.04 more QALYs (95% confidence interval [CI] 0.00-0.08) 6 months after enrolment. The mean cost per participant in the intervention arm was US $1001 (95% CI 968-1031), resulting in an incremental cost of the intervention of US $640 (95% CI 595-679). The incremental cost-effectiveness ratio for the C-MAP intervention versus TAU was US $16 254 (95% CI 7116-99 057) per QALY gained. The probability that C-MAP is cost-effective was between 66% and 83% for cost-effective thresholds between US $20 000 and US $30 000. Cost-effectiveness results remained robust to sensitivity analyses. CONCLUSIONS: C-MAP may be a valuable self-harm intervention. Further studies with longer follow-up and larger sample sizes are needed to draw reliable conclusions.

10.
Cureus ; 13(2): e13340, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33747648

RESUMEN

Ciprofloxacin is a commonly prescribed antibiotic due to its broad spectrum and good safety profile. However, recent evidence suggests that it has the propensity to cause idiosyncratic drug-induced liver injury. There are 25 reported cases of ciprofloxacin induced severe liver injury in the literature. Here, we describe another case of acute cholestatic liver injury due to ciprofloxacin. A 32-year-old female presented to the gastroenterology department with a week's history of pruritus, jaundice, and abdominal pain. Her symptoms started three days after completing a ciprofloxacin course for urinary tract infection. Her hepatic enzymes were elevated and showed a cholestatic pattern. An extensive workup, including viral serology, autoimmune profile, and imaging studies, did not reveal any underlying cholestasis cause. Her liver biopsy findings were consistent with drug-induced cholestasis. A diagnosis of ciprofloxacin-induced cholestatic liver injury was made based on the onset of symptoms and liver enzyme derangements following the use of ciprofloxacin, improvement in clinical as well as biochemical parameters after cessation of ciprofloxacin, and the liver biopsy findings. The patient received supportive treatment, and her liver enzymes returned to baseline six weeks after admission. Clinicians need to be aware that if the patient develops any liver injury symptoms while using ciprofloxacin, the drug should be stopped immediately, and a thorough evaluation should be done. The patient should also be advised to avoid ciprofloxacin and other quinolones in the future.

11.
Environ Sci Pollut Res Int ; 28(17): 21381-21395, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33411292

RESUMEN

We examine the relative performance of the industry, services, and agriculture sectors in energy conservation and reduction in CO2 emissions in Pakistan using the "spatial-temporal decomposition" method by taken data from 2006 to 2016. An efficient way to achieve low-carbon economy targets is to decompose different factors contributing to CO2 emissions, including structure effect, intensity effect, GDP gap effect, energy use efficiency effect, and economic efficiency. We classify economic sectors into three groups based on performance, i.e., sectors performing below, average, and above-average performing. Our results indicate that the economic efficiency and energy use efficiency effects in the industry sector have remained above average. In contrast, the GDP gap effect has remained below average. In the case of structure effect and intensity effect, the agriculture sector has performed on average. In contrast, the service sector has shown mixed results in all factors. The government should pay special attention to energy use structure and innovation to improve desirable output technical efficiency to achieve the target carbon emission level.


Asunto(s)
Dióxido de Carbono , Carbono , Carbono/análisis , Dióxido de Carbono/análisis , China , Desarrollo Económico , Industrias , Pakistán
12.
J Hazard Mater ; 401: 123256, 2021 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-32629356

RESUMEN

In order to improve soybean's resistance to lodging, silicon (Si) solutions at concentrations of 0,100, 200,300 mg kg-1 were applied during the seedling stage. The Si accumulation in different parts of the plants, the photosynthetic parameters of leaves and chlorophyll content, the stem bending resistance, the expression of genes of lignin biosynthesis and associated enzyme activity and sap flow rates were measured at early and late growth stages. The potential mechanisms for how Si improve growth and shade tolerance, enhances lodging resistance and improves photosynthesis were analyzed to provide a theoretical basis for the use of Si amendments in agriculture. After application of Si at 200 mg kg-1, the net photosynthetic rate of soybeans increased by 46.4 % in the light and 33.3 % under shade. The application of Si increased chlorophyll content, and fresh weight of leaves, reduced leaf area and enhanced photosynthesis by increasing stomatal conductance. The activity of peroxidase (POD), 4-coumarate:CoA ligase (4CL), cinnamyl alcohol dehydrogenase (CAD) and phenylalanine ammonia-lyase (PAL) increased during pre-and post-growth periods, whereas Si also increased lignin accumulation and inhibited lodging. We concluded that Si affects the composition of plant cell walls components, mostly by altering linkages of non-cellulosic polymers and lignin. The modifications of the cell wall network through Si application could be a useful strategy to reduce shading stress in intercropping.


Asunto(s)
Fabaceae , Glycine max , Lignina/metabolismo , Fotosíntesis , Hojas de la Planta/metabolismo , Silicio , Glycine max/genética , Glycine max/metabolismo
13.
Environ Sci Pollut Res Int ; 28(12): 14401-14422, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33206292

RESUMEN

We examine the causal impacts of the cash transfer program, namely the Benazir Income Support Program (BISP), on residential demand for electricity among ultra-poor in Pakistan. We also analyze the effects of BISP cash transfers on a household's decision to acquire electrical appliances. The empirical analysis is based on the fuzzy regression discontinuity design (RDD) using primary data collected from 1200 households. We find that BISP cash transfer has a significant positive impact on electricity demand among the target group. The cash transfer positively affects the use of few essential electric appliances, such as a washing machine and refrigerator, but not all electrical appliances. The electricity demand mainly stems from the additional use of existing electrical devices. Therefore, the extra income from BISP may not allow the recipients to move up the electric appliances ladder. The provincial analysis shows that the impact of BISP cash transfers on electricity demand varies across provinces and the development level, signifying the importance of regional heterogeneities, such as electricity supply. The findings suggest that cash transfers may facilitate the transition from traditional to modern energy to overcome the rising pollution problem and protect health. The expansion in the cash transfer program demands continuous investment in the power sector to fulfill the growing need for electricity.


Asunto(s)
Composición Familiar , Estados Financieros , Electricidad , Renta , Pakistán
14.
Clin Anat ; 33(6): 975-976, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32533563

RESUMEN

Severe acute respiratory syndrome (SARS CoV-2/COVID-19) is a highly contagious and deadly disease caused by a virus belonging to the coronaviridae family. Researchers working in histopathology laboratories, dealing with morbid samples, are particularly vulnerable to infection unless they have very strong immunity. Hence, a proper precautionary protocol is required for the safety of the laboratory staff. The current review highlights the biological and physical agents that can be used to inactivate the virus and disinfect the surrounding environment in the laboratory.


Asunto(s)
Betacoronavirus/efectos de los fármacos , Infecciones por Coronavirus/prevención & control , Desinfectantes/farmacología , Desinfección/métodos , Histología , Laboratorios/normas , Pandemias/prevención & control , Neumonía Viral/prevención & control , COVID-19 , Infecciones por Coronavirus/epidemiología , Humanos , Control de Infecciones/métodos , Personal de Laboratorio Clínico , Servicio de Patología en Hospital/organización & administración , Servicio de Patología en Hospital/normas , Neumonía Viral/epidemiología , SARS-CoV-2
15.
Funct Plant Biol ; 47(7): 592-610, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32375994

RESUMEN

In response to shading, plant leaves acclimate through a range of morphological, physiological and biochemical changes. Plants produce a myriad of structurally and functionally diverse metabolites that play many important roles in plant response to continually changing environmental conditions as well as abiotic and biotic stresses. To develop a clearer understanding of the effects of shade on soybeans at different growth stages, a comprehensive, three-year, stage-wise study was conducted. Leaf area, leaf thickness, stem diameter, chlorophyll contents, photosynthetic characteristics and other morphological and physiological features were measured along with biochemical assays for antioxidants such as superoxide dismutase, peroxidase and caralase and yield attributes of different soybean genotypes (Guixia 2, Nandou12, Nandong Kang-22, E61 and C103) under shading nets with 50% light transmittance. It was observed that early shading (VER1 and VER2) significantly decreased main stem length and main stem length/stem diameter. Later shading (R1R8 and R2R8) had significant effects on morphological characters such as branch number and pod height. In Nandou 12, the protein contents in plants shaded at R1R8, R2R8 and R5R8 were 9.20, 8.98 and 6.23% higher than in plants grown under normal light levels (CK), respectively, and the crude fat content was 9.31, 10.74 and 4.28% lower. The influence of shading in the later period on anatomy was greater than that in the earlier period. Shading reduced the light saturation point (LSP), the light compensation point (LCP) and the maximum photosynthetic rate (Pnmax), and increased the apparent quantum yield (AQ). Shading also increased the antioxidant enzyme activity in the plants, and this increase was greater with early shading than late. The variability in the chlorophyll (a + b) content and the chlorophyll a/b ratio in R2 stage plants was less than in R5 stage (VER5) plants. Similarly, the activity of antioxidant enzymes in R2 after returning the plants to normal light levels (VER2) was lower than in R5 after relighting (VER5). Compared with later shading, the early shading had a greater effect on the photosynthetic and related characteristics. The longer the shading time, the greater the adverse effects and the less able the plants' were to recover. The data collected in this study contribute to an understanding of the physiological mechanisms underlying the early and late growth stage acclimation strategies in different soybean genotypes subjected to shade stress.


Asunto(s)
Glycine max , Luz , Aclimatación , Clorofila A , Genotipo , Glycine max/genética
16.
Plants (Basel) ; 9(4)2020 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-32272796

RESUMEN

Salinity is a major abiotic stress which limits crop production, especially under rainfed conditions. Selenium (Se), as an important micronutrient, plays a vital role in mitigating detrimental effects of different abiotic stresses. The objective of this research was to examine the effect of Se fertilization on black gram (Vigna mungo) under salt stress. Our results showed that salt stress (100 mM NaCl) in leaves significantly induced oxidative damage and caused a decline in relative water content, chlorophyll (Chl), stomatal conductance (gs), photochemical efficiency (Fv/Fm), sucrose, and reducing sugars. A low dose of Se (1.5 ppm) significantly reduced hydrogen peroxide content, malondialdehyde formation, cell membrane damage, and also improved antioxidative enzyme activities, including superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase, and glutathione peroxidase under salt stress. Se-treated plants exhibited higher Chl, gs, Fv/Fm, sucrose, and reducing sugars than untreated plants in response to salt stress. In addition, Se application enhanced Se uptake and reduced Na+ uptake, but Cl- remained unaffected. Our results indicated that a low dose of Se effectively alleviated salt damage via inhibition of Na+ uptake and enhanced antioxidant defense resulting in a significant decrease in oxidative damage, and maintained gaseous exchange and PS II function for sucrose and reducing sugars accumulation in black gram.

17.
Photochem Photobiol Sci ; 19(4): 462-472, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32154819

RESUMEN

Soybean (Glycine max L.) has been extensively cultivated in maize-soybean relay intercropping systems in southwest China. However, during the early co-growth period, soybean seedlings suffer from severe shading by maize resulting in lodging and significant yield reduction. The purpose of the present research was to investigate the reasons behind severe lodging and yield loss. Therefore, four different soybean genotypes (B3, B15, B23, and B24) having different agronomic characteristics were cultivated in intercropping and monocropping planting patterns. The results showed that under different planting patterns, the stem resistance varied among genotypes (P < 0.01). The lodging resistance index of B3, B15, B23, and B24 genotypes was 70.9%, 60.5%, 65.2%, and 57.4%, respectively, under intercropping, among which the B24 genotype was less affected by the shade environment as there was little decrease in the lodging resistance index of this genotype under intercropping. The lignin content of B23 and B24 was significantly higher than that of B3 and B15 under both planting patterns. Under intercropping, the hemicellulose content of B23 and B24 stems was significantly higher than that of B3 and B15. Compared to the monocropping, the content of mannose in the structural carbohydrate of soybean stems was decreased in all genotypes except B23, but the difference was not significant. The content of xylose in the structural carbohydrate of soybean stems was significantly higher than that in B3 and B15. Mannose content showed no significant difference among genotypes. The arabinose content of B24 was significantly higher than that of B3, B15, and B23. The effective pod number, seed number per plant, seed weight per plant and yield of soybean plants were significantly decreased under intercropping. Conclusively, manipulation of structural and nonstructural carbohydrate rich soybean genotypes in intercropping systems could alleviate the yield loss due to lodging.


Asunto(s)
Celulosa/metabolismo , Glycine max/metabolismo , Lignina/metabolismo , Monosacáridos/metabolismo , Polisacáridos/metabolismo , Sacarosa/metabolismo , Celulosa/genética , Genotipo , Lignina/genética , Monosacáridos/genética , Tallos de la Planta/genética , Tallos de la Planta/fisiología , Polisacáridos/genética , Glycine max/genética , Estrés Fisiológico/genética , Estrés Fisiológico/fisiología
18.
Funct Plant Biol ; 47(4): 342-354, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32040939

RESUMEN

In China, maize-soybean relay-intercropping system follow the two main planting-patterns: (i) traditional relay-intercropping; maize-soybean equal row planting, where soybean experience severe maize shading on both sides of plants, and (ii) modern relay-intercropping; narrow-wide row planting, in this new planting pattern only one side of soybean leaves suffer from maize shading. Therefore, in this study, changes in morphological traits, cytochrome content, photosynthetic characteristics, carbon status, and the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) were investigated at 30 days after treatment (DAT) in shade-tolerant soybean variety Nandou-12 subjected to three different types of shading conditions; normal light (NL, all trifoliate-leaves of soybean plants were under normal light); unilateral shade (US, all right-side trifoliate-leaves of soybean plants from top to bottom were under shade while all the left-side of trifoliate-leaves from top to bottom were in normal light); bilateral shade (BS, all trifoliate-leaves of soybean plants were under complete shade). Compared with BS, US conditions decreased plant height and increased stem diameter, leaf area, and biomass at 30 DAT. Biomass distribution rates to stem, petiole and leaves, and photosynthetic characteristics were markedly improved by the US at all sampling stages, which proved to be a better growing condition than BS with respect to shade tolerance. The enhanced net photosynthesis and transpiration rates in the left-side leaves (LS) of soybean plants in US, when compared with the LS in BS, allowed them to produce higher total soluble sugar (by 70%) and total soluble protein (by 17%) at 30 DAT which reduce the adverse effects of shading at right-side leaves (RS) of the soybean plants. Similarly, soybean leaves under US accumulated higher proline content in US than the leaves of BS plants. Soybean leaves grown in shading conditions (LS and RS of BS and RS of US) developed antioxidative defence-mechanisms, including the accelerated activities of SOD, POD, APX, and CAT. Comparatively, soybean leaves in US displayed lower activity levels of the antioxidative enzymes than the leaves of BS plants, showing that soybean plants experienced less shade stress in US as compared with BS treatment. Overall, these results indicate that the association of improved photosynthetic characteristics, sugar and protein accumulation and optimum antioxidative defences could be an effective approach for growing soybean in intercropping environments.


Asunto(s)
Fabaceae , Glycine max , Antioxidantes , Carbono , China
19.
Sci Rep ; 9(1): 13453, 2019 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-31530859

RESUMEN

Shading conditions adversely affect flower-number and pod-number of soybeans under maize-soybean relay-intercropping (MSR). Here we reveal that leaf-removal from maize-canopy improves the photosynthetically active radiation (PAR) transmittance and dry-matter production (DMP) of soybean (especially during the co-growth phase), and compensates the maize seed-yield loss by considerably increasing soybean seed-yield. In a two-year experiment with MSR, maize-plants were subjected to different leaf-removal treatments to increase the PAR-transmittance of soybean; removal of the topmost two-leaves (R2), four-leaves (R4), six-leaves (R6), with no-removal of leaves (R0). Leaf-removal treatments improved the PAR-transmittance, photosynthetic-rate, and morphological-characteristics of soybean under MSR. At 90 days after sowing, the dry-matter of pods, and seeds was increased by 25%, and 32%, respectively under R6 than R0. Importantly, enhanced PAR-transmittance and DMP under R6 enabled soybean to initiate a greater number of flowers 182.2 plant-1 compared to 142.7 plant-1 under R0, and it also decreased the flower-abscission (by 13%, from 54.9% under R0 to 47.6% under R6). These positive responses increased the pod-number by 49% and seed-number by 28% under R6 than R0. Overall, under R6, relay-intercropped soybean produced 78% of sole-soybean seed-yield, and relay-intercropped maize produced 81% of sole-maize seed-yield and achieved the land equivalent ratio of 1.59.


Asunto(s)
Producción de Cultivos/métodos , Flores/crecimiento & desarrollo , Hojas de la Planta , Semillas/crecimiento & desarrollo , Zea mays/crecimiento & desarrollo , China , Luz , Fotosíntesis , Glycine max/crecimiento & desarrollo
20.
PeerJ ; 7: e7262, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31372317

RESUMEN

BACKGROUND: Maize-soybean relay-intercropping (MSR) is a famous system of crop production in developing countries. However, maize shading under this system directly affects the light quality and intensity of soybean canopy. This is a challenging scenario in which to implement the MSR system, in terms of varieties selection, planting pattern, and crop management since the duration of crop resource utilization clearly differs. METHODS: Therefore, this experiment aimed to elucidate the effect of leaf excising treatments from maize top to fully clarify the needs and balance of light quality and intensity of intercrop-soybean under MSR in field conditions. The effects of different leaf excising treatments (T0, no removal of leaves; T2, removal of two topmost leaves; T4, removal of four topmost leaves; T6, removal of six topmost leaves from maize plants were applied at first-trifoliate stage (V1) of soybean) on photosynthetically active radiation transmittance (PART), red to far-red ratio (R:FR), morphological and photosynthetic characteristics and total biomass production at second-trifoliate stage (V2), fifth-trifoliate stage (V5), and flowering-stage (R1) of soybean were investigated through field experiments for 2-years under MSR. RESULTS: As compared to T0, treatment T6 increased the PART and R:FR ratio at soybean canopy by 77% and 37% (V2), 70% and 34% (V5), and 41% and 36% (R1), respectively. This improved light environment in T6 considerably enhanced the leaf area index, SPAD values and photosynthetic rate of soybean plants by 66%, 25% and 49% at R1, respectively than T0. Similarly, relative to control, T6 also increased the stem diameter (by 29%) but decreased the plant height (by 23%) which in turn significantly increased stem breaking strength (by 87%) by reducing the lodging rate (by 59%) of soybean plants. Overall, under T6, relay-cropped soybean produced 78% of sole soybean seed-yield, and relay-cropped maize produced 81% of sole maize seed-yield. Our findings implied that by maintaining the optimum level of PART (from 60% to 80%) and R:FR ratio (0.9 to 1.1), we can improve morphological and photosynthetic characteristics of soybean plants in MSR. Therefore, more attention should be paid to the light environment when considering the sustainability of MSR via appropriate planting pattern selection.

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