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1.
J Environ Manage ; 351: 119888, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176379

RESUMO

Amid rising energy crises and greenhouse gas (GHG) emissions, designing energy efficient, GHG mitigation and profitable conservation farming strategies are pertinent for global food security. Therefore, we tested a hypothesis that no-till with residue retaining could improve energy productivity (EP) and energy use efficiency (EUE) while mitigating the carbon footprint (CF), water footprint (WF) and GHG emissions in rice-wheat double cropping system. We studied two tillage viz., conventional and conservation, with/without residue retaining, resulting as CT0 (puddled-transplanted rice, conventional wheat -residue), CTR (puddled-transplanted rice, conventional wheat + residue), NT0 (direct seeded rice, zero-till wheat -residue), and NTR (direct seeded rice, zero-till wheat + residue). The overall results showed that the NTR/NT0 had 34% less energy consumption and 1.2-time higher EP as compared to CTR/CT0. In addition, NTR increased 19.8% EUE than that of CT0. The grain yield ranged from 8.7 to 9.3 and 7.8-8.5 Mg ha-1 under CT and NT system, respectively. In NTR, CF and WF were 56.6% and 17.9% lower than that of CT0, respectively. The net GHG emissions were the highest (7261.4 kg CO2 ha-1 yr-1) under CT0 and lowest (4580.9 kg CO2 ha-1 yr-1) under NTR. Notably, the carbon sequestration under NTR could mitigate half of the system's CO2-eq emissions. The study results suggest that NTR could be a viable option to offset carbon emissions and water footprint by promoting soil organic carbon sequestration, and enhancing energy productivity and energy use efficiency in the South Asian Indo-Gangetic Plains.


Assuntos
Gases de Efeito Estufa , Oryza , Solo/química , Triticum , Carbono/análise , Dióxido de Carbono , Agricultura/métodos , Água
2.
J Environ Manage ; 328: 116990, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36508980

RESUMO

Methane (CH4) is the main greenhouse gas emitted from rice paddy fields driven by methanogens, for which methanogenic abundance on CH4 production has been intensively investigated. However, information is limited about the relationship between methanogenic diversity (e.g., richness and evenness) and CH4 production. Three independent field experiments with different straw managements including returning method, burial depth, and burial amount were used to identify the effects of methanogenic diversity on CH4 production, and its regulating factors from soil properties in a rice-wheat cropping system. The results showed that methanogenic evenness (dominance) can explain 23% of variations in CH4 production potential. CH4 production potential was positively related to methanogenic evenness (R2 = 0.310, p < 0.001), which is driven by soil organic carbon (SOC), available phosphorus (AP), and nitrate (NO3-) through structure equation model (SEM). These findings indicate that methanogenic evenness has a critical role in evaluating the responses of CH4 production to agricultural practices following changes in soil properties. The SEM also revealed that SOC concentration influenced CH4 production potential indirectly via complementarity of methanogenic evenness (dominance) and available phosphorus (AP). Increasing SOC accumulation improved AP release and stimulated CH4 production when SOC was at a low level, whereas decreased evenness and suppressed CH4 production when SOC was at a high level. A nonlinear relationship was detected between SOC and CH4 production potential, and CH4 production potential decreased when SOC was ≥14.16 g kg-1. Our results indicated that the higher SOC sequestration can not only mitigate CO2 emissions directly but CH4 emissions indirectly, highlighting the importance to enhance SOC sequestration using optimum agricultural practices in a rice-wheat cropping system.


Assuntos
Euryarchaeota , Gases de Efeito Estufa , Oryza , Solo/química , Carbono/análise , Agricultura/métodos , Metano/análise , Triticum , Óxido Nitroso/análise
3.
J Environ Manage ; 329: 117065, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36566726

RESUMO

Recommended management practices (RMPs, e.g., manuring, no-tillage, crop residue return) can increase soil organic carbon (SOC), reduce greenhouse gas emissions, and maintain soil health in croplands. However, there is no consensus on how RMPs affect the SOC storage potential of cropland soils for climate change mitigation. Here, based on 2301 comparisons from 158 peer-reviewed papers, a meta-analysis was conducted to explore management-induced SOC stock changes and their variations under different conditions. The results show that SOC stocks in the 0-20 cm layer were increased by 31.8% when chemical fertilization combined with manure application was compared with no fertilizer; 9.98% when no-tillage was compared with plow tillage; and 10.84% when straw return was compared with removal. The RMPs favorably increased SOC stock in arid areas, and in alkaline and fine-textured soils. Initial SOC, carbon-nitrogen ratio, and experimental duration could also affect SOC storage. Compared with the initial SOC stock, RMPs increased the SOC sequestration potential by 2.6-4.5% in the 0-20 cm soil depth, indicating that these practices can help China achieve targets to increase SOC by 4.0‰. Hence, it is essential to implement RMPs for climate change mitigation and soil fertility improvement.


Assuntos
Agricultura , Solo , Solo/química , Agricultura/métodos , Carbono/análise , Produtos Agrícolas , China , Sequestro de Carbono , Esterco/análise
4.
Ecotoxicol Environ Saf ; 230: 113165, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34998263

RESUMO

In modern agriculture and globalization, the release of trace metals from manufacturing effluents hinders crop productivity by polluting the atmosphere and degrading food quality. Sustaining food safety in polluted soils is critical to ensure global food demands. This review describes the negative effects of trace metals stress on plant growth, physiology, and yield. Furthermore, also explains the potential of biochar in the remediation of trace metal's contaminations in plants by adoption of various mechanisms such as reduction, ion exchange, electrostatic forces of attraction, precipitation, and complexation. Biochar application enhances the overall productivity, accumulation of biomass, and photosynthetic activity of plants through the regulation of various biochemical and physiological mechanisms of plants cultivated under trace metals contaminated soil. Moreover, biochar scavenges the formation of reactive oxygen species, by activating antioxidant enzyme production i.e., ascorbate peroxidase, catalase, superoxide dismutase, peroxidase, etc. The application of biochar also improves the synthesis of stressed proteins and proline contents in plants thus maintaining the osmoprotectant and osmotic potential of the plant under contaminates stress. Integrated application of biochar with other amendments i.e., microorganisms and plant nutrients to improve trace metal remediation potential of biochar and improving crop production was also highlighted in this review. Moreover, future research needs regarding the application of biochar have also been addressed.

5.
J Environ Manage ; 265: 110549, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32275251

RESUMO

A site experiment was conducted to assess temporal dynamics of soil organic carbon (SOC) and the drivers under no-tillage (NT) and residue retention (RR) in the North China Plain (NCP). The results indicated that NT and RR can significantly increase SOC up to a depth of 30 cm. On average, NT increased SOC by 8.1-34.5% compared with PT, and RR increased SOC by 3.5-14.4% compared with R0 at 0-10 cm. Increases in SOC under NT or RR could be increased by 4-10 percentage points through the significantly positive interactions of NT and RR. Among the sources of SOC variations, tillage-induced variations accounted for 74.4 and 44.3% of the total variations in SOC at 0-5 cm for wheat and maize season, respectively. Experimental duration was also a significant source of variation. Stepwise regression indicated dynamics in SOC at 0-5 cm mainly due to the positive effects of precipitation, the negative effects of soil bulk density for the wheat season, the negative effects of radiation for the maize season, and antagonistic effects of temperature between wheat and maize season. Generally, positive effects of NT and RR on SOC were both confirmed, but fluctuations and variations induced by interactions of practices and seasonal climatic conditions were also significant in the NCP.


Assuntos
Solo , Triticum , Agricultura , Carbono , China , Zea mays
6.
Nat Prod Res ; : 1-9, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38462767

RESUMO

A series of novel ester derivatives 2 - 7, of natural product geodin 1, isolated from the soft coral-derived fungus Aspergillus sp., were designed and semi-synthesised through one step reaction with high yield. Compound 5 showed strong antifouling inhibitory activities with MIC of 4.80 µM while compound 4 showed selective inhibitory activities with MICs values 8.59 µM against Aeromonas salmonicida and Pseudomonas aeruginosa (Sea-Nine 211, MIC = 0.27 µM). Compounds 3, 4 and 6 showed potent anti-pathogenic inhibitory activities with MICs of 2.29 µM, 4.29 µM and 4.56 µM respectively against Staphylococcus aureus (Ciprofloxacin, MIC = 0.156 µM). Compound 2 showed weak inhibitory activity against A. salmonicida with MIC 18.75 µM (Sea-Nine 211, MIC = 0.27 µM) and with MICs 9.38 µM against S. aureus (ciprofloxacin, MIC = 0.156 µM). However, compound 7 showed very low antibacterial activities with MIC = >20 µM. The preliminary structure-activity relationships of compounds 2 - 7 further prove that the modification of 4-OH group of natural product geodin 1 improves the antibacterial activities such as antifouling and anti-pathogenic activities.

7.
Anim Biosci ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38665082

RESUMO

Objective: To investigate the prevalence of paratuberculosis in cattle and buffaloes at twelve public dairy farms in Punjab, Pakistan. Methods: A total of 2181 more than two-year-old animals (1242 cattle and 939 buffaloes) were tested by avian tuberculin, i.e., killed purified protein derivative (PPD) of Mycobacterium avium paratuberculosis and indirect ELISA. Blood and fecal samples were collected from tuberculin positive animals. These samples were further processed by indirect ELISA. The data were analyzed using frequency analysis and logistic analysis procedures. Results: The prevalence of paratuberculosis at public dairy farms was 3.8%, as determined by tuberculin + ELISA test. It varied from 0.71-13.5% with a 100% herd prevalence. Multivariate logistic regression analysis revealed that species, milk production, total animals, total small ruminants, and total buffaloes were significantly associated with the occurrence of paratuberculosis. Odd ratio analysis revealed that with a one-kilogram increase in body weight, there will be a 0.006% increase in disease occurrence. With the increase in one animal in small ruminants and buffaloes, there will be 0.008% and 0.42% greater chances of developing paratuberculosis, respectively. Bivariate logistic regression analysis of cattle and buffaloes revealed that farm number, age, and total number of cattle were significantly associated with the occurrence of paratuberculosis. A one-month increase in lactation length increases the chance of tuberculosis by 0.004%; similarly, a one-liter increase in milk production increases the chance of disease by 10%. With each additional buffalo in the herd, there will be a 0.007% greater chance for the occurrence of paratuberculosis. Conclusion: This study concluded that tuberculin testing can be used in conjunction with ELISA to screen animals for paratuberculosis in countries with scarce resources, such as Pakistan. The efficacy of disease diagnosis can be improved by combining multiple tests.

8.
Sci Total Environ ; 945: 174007, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38885710

RESUMO

Climate warming poses a serious threat to soil biodiversity and crop yield. Application of organic fertilizer has been extensively practiced to improve soil health and crop productivity. However, information is limited about the effects of organic fertilizer on microbial communities and diversity (richness) under warming. Thus, to investigate the interactive effects of temperature (ambient temperature and warming) and fertilizer (chemical fertilizer and partial substitution of chemical fertilizer with organic fertilizer) on microbial properties and wheat yield, a two-factorial pot experiment was conducted using soils with high and low fertility The results showed that warming and organic fertilizer had minor effects on bacterial Shannon and Simpson indexes. Due to concomitant reductions in soil moisture, warming decreased the average Chao index by 5.4 % and Ace index by 3.8 % for soils with high and low fertility (P < 0.05). High-throughput sequence presented that dominated genus was Bacillus with spore-forming ability. Under warming and drying conditions, microbes with adaptive traits (spore-forming ability) would outcompete the other microbes, and decrease microbial Chao and Ace index (richness). However, organic fertilizer counteracted the adverse effects of warming on microbial richness attributed to positive interaction between temperature and fertilizer on soil nutrients and organic carbon. The strong relationships between bacterial richness and wheat yield, as well as soil nutrients, highlighted the importance of soil biodiversity in improving soil nutrients and crop productivity. Partial substitution of chemical fertilizer with organic fertilizer significantly increased wheat yield by 27.1 % and 14.9 % under ambient temperature and by 28.0 % and 19.6 % under warming for soils with high and low fertility, respectively. Overall, this study provided the possibility to increase bacterial richness related to nutrient turnover and crop production by organic fertilizer application with reduced chemical fertilizer, especially under climate warming.


Assuntos
Fertilizantes , Microbiologia do Solo , Solo , Triticum , Triticum/microbiologia , Solo/química , Biodiversidade , Aquecimento Global , Microbiota , Bactérias , Agricultura/métodos
9.
J Clin Tuberc Other Mycobact Dis ; 31: 100359, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36945658

RESUMO

Summary background: The coronavirus 2019 pandemic was caused by a new single-strand RNA virus that originated from Wuhan, China, and infected more than 190 countries. The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) coinfection with tuberculosis posed a serious public health concern and complicated the prognosis and treatment of patients. Since both are respiratory diseases, the sign and symptoms may overlap and could have synergistic effects on the host that can increase mortality during coinfection. The present investigation reported the clinical characteristics of patients having coinfection of COVID-19 and tuberculosis (COVID-TB). Methods: We performed a retrospective investigation on COVID-19 infection in tuberculosis patients between the years 2020 and 2021. The SARS-CoV-2 was confirmed by PCR and the COVID-TB epidemiological and clinical findings were recorded on the day of admission and followed up for 25 days. Results: The mean age of the COVID-19 patients was 50 ± 15 years, 76.36% were male and 23.64% were female. Weight loss, sore throat, whooping cough, chest pain, and vomiting were common symptoms, and asthma, diabetes, arthritis, and hypertension were found as co-morbidities in COVID-TB. The D-dimer, lactate dehydrogenase, C-reactive protein, erythrocyte sedimentation rate, and creatine kinase levels increased 14-fold, 12.5-fold, 11-fold, 10-fold, and 7-fold respectively during COVID-TB. The patients suffered from hyperferritinemia and lymphocytopenia which increased the likelihood of death. The levels of D-dimer, lactate dehydrogenase, C-reactive protein, erythrocyte sedimentation rate, and creatinine kinase were positively correlated with patient age. The chest radiograph showed the infectious agents have consolidated opacity and peripheral dissemination in the lungs. Conclusion: Tuberculosis coinfection augmented the severity of COVID-19 and the likelihood of death, and high vigilance is recommended for respiratory pathogens in COVID-19.

10.
Front Vet Sci ; 10: 1128522, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36968473

RESUMO

The present study investigated the adverse effects of arsenic and chromium in broilers and ascertained the role of vitamin E and bentonite in alleviating their harmful effects. For this purpose, we experimented on 180 one-day-old broiler chickens. The feed was administered to broiler chicks of groups 2, 6, 7, 8, and 9 chromium @ (270 mg.kg-1 BW). Groups 3, 6, 7, 8, and 9 were administered arsenic @ (50 mg.kg-1 BW). Groups 4, 7, and 9 received vitamin E (150 mg.kg-1 BW), and groups 5, 8, and 9 received bentonite (5%), respectively. Group 1 was kept in control. All the broiler chicks treated with chromium and arsenic showed a significant (p < 0.05) decline in erythrocytic parameters on experimental days 21 and 42. Total proteins decreased significantly, while ALT, AST, urea, and creatinine increased significantly (p < 0.05). TAC and CAT decreased significantly (p < 0.05), while TOC and MDA concentrations increased significantly (p < 0.05) in chromium and arsenic-treated groups on experimental days 21 and 42. Pearson correlation analysis revealed a strong positive correlation between TAC and CAT (Pearson correlation value = 0.961; p < 0.001), similarly TOC and MDA positive correlation (Pearson correlation value = 0.920; p < 0.001). However, TAC and CAT showed a negative correlation between TOC and MDA. The intensity of gross and microscopic lesions was more in chromium (270 mg.kg-1) and arsenic (50 mg.kg-1) singly or in combination-treated groups. Thus, broiler chicks treated with chromium plus arsenic exhibited higher gross and microscopic lesion intensity than other treated groups. Fatty degeneration, severe cytoplasmic vacuolar degeneration, and expansion of sinusoidal spaces were the main lesions observed in the liver. Kidneys showed renal epithelial cells necrosis, glomerular shrinkage, and severe cytoplasmic vacuolar degeneration. Co-administration of bentonite along with chromium and arsenic resulted in partial amelioration (group 8) compared to groups 7 and 9, administered arsenic + chromium + vitamin E and arsenic + chromium + vitamin E + bentonite, respectively. It was concluded that arsenic and chromium cause damage not only to haemato-biochemical parameters but also lead to oxidation stress in broilers. Vitamin E and bentonite administration can ameliorate toxicity and oxidative stress produced by arsenic and chromium.

11.
Environ Sci Pollut Res Int ; 30(7): 17629-17643, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36198981

RESUMO

The ever-increasing trend of greenhouse gas (GHG) emissions is accelerating global warming and threatening food security. Environmental benefits and sustainable food production must be pursued locally and globally. Thus, a field experiment was conducted in 2015 to understand how to balance the trade-offs between agronomic productivity and environment quality in the North China Plain (NCP). Eight treatments consisted of two factors, i.e., (1) tillage practices: rotary tillage (RT) and no-till (NT), and (2) cropping sequences (CS): maize-wheat-soybean-wheat (MWSW), soybean-wheat-maize-wheat (SWMW), soybean-wheat (SW), and maize-wheat (MW). The economic and environmental benefits were evaluated by multiple indicators including the carbon footprint (CF), maize equivalent economic yield (MEEY), energy yield (EY), and carbon sustainability index (CSI). Compared with NT, RT increased the EY and MEEY, but emitted 9.4% higher GHGs. Among different CSs, no significant reduction was observed in CF. The lowest (2.0 Mg CO2-eq ha-1 year-1) and the highest (5.6 Mg CO2-eq ha-1 year-1) CF values were observed under MW and SWMW, respectively. However, CSs with soybean enhanced MEEY and the net revenue due to their higher price compared to that of MW. Although the highest CSI was observed under RT-MW, soybean-based crop rotation could offset the decline in CSI under NT when compared to that for RT. These findings suggest that conservation agriculture (CA) could enhance the balance in trade-offs between economic and environmental benefits. Additional research is needed on how to achieve high crop production by establishing a highly efficient CA system in the NCP.


Assuntos
Agricultura , Dióxido de Carbono , Dióxido de Carbono/análise , Produção Agrícola , Produtos Agrícolas , China , Zea mays , Triticum , Glycine max , Solo
12.
Sci Total Environ ; 819: 153089, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35038532

RESUMO

With increasing attention being placed on mitigating global warming and achieving agricultural sustainable intensification, conservation agriculture practices have gradually been implemented in the North China Plain (NCP). However, there are still knowledge gaps on the effects of conservation practices on greenhouse gas (GHG) emissions in this area. In this study, a four-year field experiment was conducted from 2014 to 2018 to assess the effects of tillage and crop residue management practices on the emissions of nitrous oxide (N2O) and methane (CH4). Subsequently, crop yields, area-scaled and yield-scaled total non-carbon dioxide (CO2) GHG emissions were assessed. Our research found that no-till (NT) decreased N2O emissions by 22.6% compared with conventional tillage (CT) in winter wheat (Triticum aestivum L.) seasons, but there was no difference between tillage practices in summer maize (Zea mays L.) seasons. Crop residue retention practice (+R) increased N2O emissions by 28.1% and 26.7% compared with residue removal practice (-R) in winter wheat and summer maize seasons, respectively. The NT soils took up more CH4 compared with the CT soils in summer maize seasons. Area-scaled total non-CO2 GHG emissions showed trends similar to those of N2O emission. Since crop residue retention improved the maize yield compared with the residue removal treatments, yield-scaled total non-CO2 GHGs emission did not differ between residue management practices in summer maize seasons. Our four-year field measurements indicated that no-till practice could be more useful as an option to mitigate non-CO2 GHG emissions in the wheat - maize cropping system.


Assuntos
Gases de Efeito Estufa , Agricultura , China , Fertilizantes/análise , Óxido Nitroso/análise , Solo , Triticum , Zea mays
13.
Microsc Res Tech ; 85(7): 2361-2380, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35247018

RESUMO

This research aimed to explore the melliferous bee flora pollen from arid zones of District Attock, Islamabad Capital and Rawalpindi. Morpho-palynological features has provided key information for the classification and help to explain the taxonomy of several genera and species. Therefore, in this work, we examined the morphological characters of pollen potentially to be used for the species delimitation of bee flora. A total of 18 bee floral species, classified into 12 different families were collected, pressed, identified and then acetolyized to observe the grains under microscopy. Bee pollen can be described by small, medium to large sized morphotypes presenting five types of shapes, prolate spheroidal in (seven species), sub-prolate (six species), oblate spheroidal (three species), oblate and prolate (one species each) was examined. The observed polar and equatorial diameter were found maximum in Zea mays 73.5 µm and Pelargonium inquinans 66.75 µm respectively. Pollen of six different types was found namely: tricolporate, 3-zonocolporate, monoportae, tetracolporate, tetraporate and mononsulcate. Whereas highest value of colpi length was measured in Grewia tenax (24.55 µm). Exine surface nature of pollen was examined echinate psilate and scabrate. Exine thickness noted to be maximum in Verbena tenuisecta (8.40 µm) and minimum in Citrus macrocarpa (0.4 µm). Bee floral species considered difficult to identify based on other morphological traits were successfully distinguished using pollen quantitative and qualitative traits, confirming the importance of pollen morphology to diagnose characters to correctly identify honeybee flora. RESEARCH HIGHLIGHTS: Pollen diversity among honeybee flora. Highly variations observed via microscopy in pollen micromorphology. Palyno-morph has taxonomic value for the identification of honeybee floral species.


Assuntos
Fosmet , Animais , Abelhas , Microscopia Eletrônica de Varredura , Fenótipo , Plantas , Pólen/anatomia & histologia
14.
Environ Sci Pollut Res Int ; 29(35): 52534-52543, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35262890

RESUMO

Delay sowing of wheat is a common problem in Punjab that exacerbates serious yield loss. To reduce yield loss and improve yield, different combinations of foliar-applied bioregulator and micronutrients, control (CK), zinc (Zn), boron (B), thiourea (TU), Zn + B (ZnB), Zn + TU (ZnTU), B + TU (BTU), Zn + B + TU (ZnBTU) were applied at booting and grain filling stages in delayed sown wheat in 2017-18 and 2018-19. The results showed that ZnBTU treatment significantly increased leaf area index by 25.06% and 23.21%, spike length by 15.11% and 19.65% in 2017 and 2018, respectively, compared to CK. The ZnBTU treatment also increased 1000-grain weight by 21.96% and 22.01% in 2017 and 2018, respectively, compared to CK. Similarly, higher Zn, B and N contents in straw and grain were recoded for ZnBTU treatment which was statistically similar to ZnB and ZnTU treatments. Overall, ZnBTU treatment also increased the photosynthetic rate, transpiration rate, stomatal conductance by 46.67%, 26.03%, 76.25% and decreased internal CO2 by 28.18%, compared to CK, respectively. Moreover, ZnBTU also recorded the highest grain yield in 2017-18 (25.05%) and 2018-19 (28.49%) than CK. In conclusion, foliar application of ZnBTU at the booting and grain filling stages of delayed sown wheat could be a promising strategy to increase grain yield.


Assuntos
Biofortificação , Triticum , Grão Comestível , Micronutrientes , Triticum/fisiologia , Zinco
15.
Sci Total Environ ; 842: 156822, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35738372

RESUMO

Conservation agriculture (CA) can be an important strategy for improving soil organic carbon (SOC) and total nitrogen (TN). Numerous studies have examined SOC and TN dynamics in different cropping systems. However, there is some uncertainty regarding the relative impacts of some CA practices, and it is not always clear how other agricultural management, particularly nitrogen addition, interacts with these practices to influence SOC and TN sequestration. Thus, we conducted a global meta-analysis of 752 comparisons from 97 papers to analyze the impacts of nitrogen fertilizers and CA practices (namely crop diversification, minimal soil disturbance (no-tillage) and permanent soil cover), on SOC and TN content worldwide. Overall, our study showed the most significant increase of SOC [21.39 % (CI = 15.16 to 28.64)] and TN [54.34 % (CI = 26.19 to 96.69)] stock with CA practices compared to conventional practices in the 0-15 cm soil depth. It also showed a significant increase in SOC and TN stock with all the individual components of CA compared to conventional practices in the 0-15 cm soil depth. However, the impact of CA on SOC and TN is reduced in 0-60 cm depths compared to surface soil depths due to the limited input of crop residue deeper in the soil profile. Manure and manure mixed with mineral-N led to greater SOC sequestration [20.67 % (CI = 15.23 to 27.10) and 41.67 % (CI = 31.03 to 52.79), respectively] than mineral-N alone [9.08 % (CI = 6.44 to 11.83)]. Cropping systems that included legume residue decreased the C/N ratio. This highlights that adequate mineral-N fertilizer addition may also be required in conjunction with residue retention practices to improve SOC and TN content. Overall, these results show that CA systems that include legume residue and manure mixed with mineral-N have great potential to increase SOC and TN, particularly at 0-15 cm and 0-30 cm soil depth.


Assuntos
Nitrogênio , Solo , Agricultura/métodos , Carbono/química , Sequestro de Carbono , Fertilizantes , Esterco , Minerais , Nitrogênio/análise , Solo/química
16.
Sci Total Environ ; 847: 157518, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35878862

RESUMO

Conservation agriculture (CA) has been adopted worldwide on about 200 Mha to enhance soil organic carbon (SOC) for mitigating climate change. However, as a crucial mechanism to sequester SOC, how the protection of aggregates responds to the interaction between no-till and crop rotations (two principles of CA) remains unknown. Thus, a field experiment with six treatments [e.g., no-till or rotary tillage under the maize-wheat-soybean-wheat system (NT-MWSW, RT-MWSW), no-till or rotary tillage under the maize-wheat system (NT-MW, RT-MW), and no-till or rotary tillage under the soybean-wheat system (NT-SW, RT-SW)] was conducted from June 2018 to June 2021 in the North China Plain (NCP) to assess their effects on aggregation and SOC. Results indicated that macroaggregates (> 0.25 mm) were the main contributors to the soil carbon (C) pool, comprised 64.7-87.3 % of aggregates, and encompassed 64.9-73.1 % of the SOC stock. NT increased not only the proportion of macroaggregates but also aggregate stability (i.e., mean weight diameter and geometric mean diameter). Significant positive effects from legumes were observed under NT. SW increased by 13.6 % macroaggregate-associated SOC under NT in 0-20 cm compared to that under MW. Additionally, the conversion rate of straw C input under NT-SW was higher than that in other treatments, augmenting it by 9.4-21.9 %. This may be attributed to the higher macroaggregate total nitrogen (increased by 1.7-15.9 %) in 0-10 cm under legume-based crop rotations compared to that under MW, resulting in lower C: N ratios, which promoted the decomposition of straw. Furthermore, the total potential mineralization of macroaggregates under NT legume-based crop rotations was 3.0-16.0 % higher than that of MW. Thus, a legume-based NT system can significantly improve soil macro-aggregation, increase the conversion rate of straw C input, and reduce C loss, which can be a viable practice to enhance SOC sequestration capacity under CA in the NCP.


Assuntos
Fabaceae , Solo , Agricultura/métodos , Carbono/análise , Sequestro de Carbono , China , Produção Agrícola , Nitrogênio , Verduras
17.
PLoS One ; 16(9): e0256075, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34543316

RESUMO

Water scarcity is a major concern for sunflower production in the semi-arid and arid regions of the world. Potassium (K) application has been found effective to alleviate the influence of drought stress; however, the impact of drought stress on seed quality of sunflower has not been reported frequently. Therefore, a field experiment was performed to determine the optimum K requirement for mitigating the adverse effects of water stress and improving growth and seed quality of spring-planted sunflower. Sunflower plants were exposed to water stress at different growth stages, i.e., Io = no stress (normal irrigation), I1 = pre-anthesisi stress (irrigation skipped at pre-anthesis stage), I2 = anthesis stress (irrigation skipped at anthesis stage) and I3 = post-anthesis stress (irrigation skipped at post-anthesis stage). Potassium was applied at four different rates, i.e., Ko = 0, K1 = 50, K2 = 100 and K3 = 150 kg ha-1. The results revealed that water stress at pre- and post-anthesis stages significantly reduced plant height, head diameter, number of achenes, oleic acid contents, and phosphorus (P) uptake. However, pre-anthesis stress improved linoleic acid contents. Treatment IoK3 (stress-free with 150 kg ha-1 K) was optimum combination for 1000-achene weight, biological and achene yields, oil contents, protein contents, and N and P uptake. Results indicated that a higher amount of K and irrigation resulted in higher yield, whereas yield and yield components decreased with early-stage water stress. Nevertheless, potassium application lowered the impacts of waters stress compared to no application. Keeping in view these results, it is recommended that sunflower must be supplied 150 kg ha-1 K in arid and semi-arid regions to achieve higher yield and better seed quality.


Assuntos
Irrigação Agrícola/métodos , Secas , Helianthus/crescimento & desenvolvimento , Potássio/farmacologia , Estações do Ano , Sementes/crescimento & desenvolvimento , Estresse Fisiológico , Clima Desértico , Helianthus/efeitos dos fármacos , Helianthus/metabolismo , Sementes/efeitos dos fármacos , Sementes/metabolismo
18.
Front Plant Sci ; 12: 809322, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35178057

RESUMO

Cadmium (Cd) contamination of croplands jeopardizes sustainable crop production and human health. However, curtailing Cd transfer and mobility in the rhizosphere-plant system is challenging. Sole application of biochar (BC) and thiourea (TU) has been reported to restrain Cd toxicity and uptake in plants. However, the combined applications of BC and TU in mitigating the harmful effects of Cd on plants have not yet been thoroughly investigated. Therefore, this study attempts to explore the integrated impact of three maize stalk BC application rates [B 0 (0% w/w), B 1 (2.5% w/w), and B 2 (5% w/w)] and three TU foliar application rates [T 0 (0 mg L-1), T 1 (600 mg L-1), and T 2 (1,200 mg L-1)] in remediating the adverse effects of Cd on maize growth, development, and physiology. Results demonstrated that Cd concentration in soil inhibited plant growth by reducing leaf area, photosynthesis activity, and enhanced oxidative stress in maize. Nevertheless, BC and TU application in combination (B 2 T 2) improved the fresh biomass, shoot height, leaf area, and photosynthesis rate of maize plants by 27, 42, 36, and 15%, respectively, compared with control (B 0 T 0). Additionally, the oxidative stress values [malondialdehyde (MDA), hydrogen peroxide (H2O2), and electrolyte leakage (EL)] were minimized by 26, 20, and 21%, respectively, under B 2 T 2 as compared with B 0 T 0. Antioxidant enzyme activities [superoxide dismutase (SOD) and catalase (CAT)] were 81 and 58%, respectively, higher in B 2 T 2 than in B 0 T 0. Besides, the shoot and root Cd concentrations were decreased by 42 and 49%, respectively, under B 2 T 2 compared with B 0 T 0. The recent study showed that the integrated effects of BC and TU have significant potential to improve the growth of maize on Cd-contaminated soil by reducing Cd content in plant organs (shoots and roots).

19.
J Ethnopharmacol ; 210: 88-94, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-28807851

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: From early times man has used medicinal plants for the treatment of various ailments and basic health care needs. The use of herbal medicines has increased day by day and with this, so do reports of adverse events, poisoning, and suspected toxicity. Similarly, the indigenous communities of Neelum Valley in Azad Kashmir commonly use Arnebia benthamii (Wall. ex G.Don) I.M.Johnst. for medicinal purposes to treat various human aliments. Besides their medicinal uses, it also contains hepatotoxic pyrrolizidine alkaloids (PAs). AIM OF THE STUDY: This explorative study underscores two major aspects about this herbal medicine. Firstly we aimed to document the traditional therapeutic uses of Arnebia benthamii in Neelum Valley, Azad Kashmir. Secondly, to determine the presence or absence of hepatotoxic pyrrolizidine alkaloids and if they are within the suggested limit for the use of herbs in excess. MATERIALS AND METHODS: Interviews, group discussions, and inquiries were carried out from July to September 2016 with local indigenous and elder people. In the laboratory, the plant was investigated for pyrrolizidine alkaloids by using high performance liquid chromatography (HPLC). RESULTS: A total of 30 respondents were interviewed. They explained the preferred preparation, parts used, and treatment indications. Treatment of fever along with kidney and liver problems are the three principle uses. Among the different parts of Arnebia benthamii, 43% respondents preferred aerial parts for the herbal formulation, followed by whole plants, and leaves. Decoction was the major mode of preparation and all herbal preparations were administrated orally. This study reports, for the first time according to our literature review, a study of Arnebia benthamii with regard to PA determination. By using column Zorbax SB-Aq and acetonitrile-water gradient as the mobile phase, HPLC results showed that the aerial parts of the plant were PA positive, and (1) Europine, Heliotrine (2), Lycopsamine (3), and Echimidine (4) were identified. CONCLUSIONS: This study has revealed two new findings of significance to herbal medicine producers, practitioners, and consumers of Arnebia benthamii First, local knowledge regarding the medicinal uses of Arnebia benthamii were documented in five sites of Neelum Valley, Azad Kashmir. The use of this plant by a large part of the population in the study area shows the importance for their therapeutic benefits. Unfortunately, the second finding of this study shows that Arnebia benthamii contains hepatotoxic PAs. Hence, we advised to the government regulatory authorities and non-governmental organizations that use of this plant as herbal medicine should be excluded before more accurate quality control tests.


Assuntos
Boraginaceae/química , Medicina Tradicional/métodos , Preparações de Plantas/administração & dosagem , Alcaloides de Pirrolizidina/análise , Adulto , Idoso , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Cromatografia Líquida de Alta Pressão/métodos , Etnofarmacologia , Humanos , Índia , Medicina Tradicional/efeitos adversos , Pessoa de Meia-Idade , Fitoterapia/efeitos adversos , Fitoterapia/métodos , Preparações de Plantas/efeitos adversos , Alcaloides de Pirrolizidina/administração & dosagem , Alcaloides de Pirrolizidina/efeitos adversos
20.
Bol. latinoam. Caribe plantas med. aromát ; 20(2): 203-214, 2021. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1342225

RESUMO

The current study was designed to investigate the traditional recipes used to treat cough in Tehsil Piran, Malakand, Pakistan. These recipes were explored and quantitively analyzed for the first time. A total of 30 species of the plants, 6 animal products and one salt were reported to be used by the community to treat cough. Punica granatum L. and Olea ferruginea Royle dominated with Use value (UV) of 0.84 and Origanum vulgare L. with least use value of 0.1. The frequency citation (FC) of the Papaver somniferum L. is higher (98) while the lowest one is Verbascum thapsus L. (0.13). The large number of traditional recipes used for cough in this area shows that primary health care is still amalgamated in this culture. In future studies, these recipes may be further exploited as a base for modern medicine.


Este estudio fue diseñado con el propósito de investigar las recetas tradicionales utilizadas para tratar la tos en Tehsil Piran, Malakand, Pakistán. Estas recetas fueron exploradas y analizadas cuantitativamente por primera vez. Se constata que la comunidad utilizó un total de 30 especies de plantas, 6 productos animales y una sal para tratar la tos. Punica granatum L. y Olea ferruginea Royle se destacaron con un valor de uso (UV) de 0.84 y Origanum vulgare L. con un valor de uso mínimo de 0.1. La cita de frecuencia (FC) del Papaver somniferum L. es más alta (98) mientras que la más baja es Verbascum thapsus L. (0.13). La gran cantidad de recetas tradicionales utilizadas para la tos en esta área muestra que la atención primaria de salud todavía está amalgamada en esta cultura. En futuros estudios, estas recetas pueden explotarse aún más como base para la medicina moderna.


Assuntos
Humanos , Plantas Medicinais , Tosse/tratamento farmacológico , Etnofarmacologia , Paquistão
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