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Organic based fertilizers is crucial for maintaining soil fertility, increasing crop production, and mitigating climate change. Among various organic fertilizers, vermicompost (VC) has been found to be one of the promising options for enhancing soil fertility and productivity. However, there are limited studies on the agronomic effects of vermicomposts in Nepal. In this study, a pot culture experiment was conducted inside a greenhouse to assess the agronomic and economic effects of four different commercially available vermicomposts, available in both reduced and original moisture forms, on okra. Nine treatments with three replications were arranged in a completely randomized design (CRD). These treatments included Divya vermicompost with both reduced (DvRM: 28.82 %) and original moisture (DvOM: 62.17 %); Praramva vermicompost with reduced (PvRM: 29.63 %) and original moisture (PvOM: 54.65 %), Bio-Comp vermicompost with reduced (BvRM: 26.75 %) and original moisture (BvOM: 49.77 %), Sathi vermicompost with reduced (SvRM: 28.52 %) and original moisture (SvOM: 65.18 %), and a control (CK: non-fertilized treatment). All VC treatments, whether in reduced or original moisture forms, showed better performance on plant growth parameters and fruit yield compared to the control. There was no significant difference between the four types of VCs, in either moisture form. The average number of fruits per pot in VC treatments (ranging from 5.5 to 8.0 fruits per pot) increased by 94 % compared to CK (3.5 fruits). Similarly, total fruit yield increased by 126 % in VC treatments (ranging from 16213 kg ha-1 to 23193 kg ha-1) compared to the CK (8260 kg ha-1). The benefit to cost ratio (B:C) of all the VCs was above 1 (B:C > 1), ranging from 1.00 to 1.59, illustrating the economic benefit of using vermicompost in okra cultivation. The findings suggest that farmers should consider the widespread use of vermicomposts to increase both crop productivity and farm profitability, thereby sustaining their livelihoods.
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Several innovative fertilizers and application methods, along with different decision support tools have been developed to improve nitrogen use efficiency (NUE) and crop yields, but their comparative study in maize is yet to be done in Nepal. Thus, we evaluated different slow-release N fertilizers and decision-making tools for real-time N management compared with the common urea on their effectiveness in increasing NUE, grain yield and economic return of spring maize (Zea mays L. cv. Rampur Hybrid-10). A field trial was conducted at Dang Valley of Nepal in a Randomized complete block design with three replications and seven treatments; N omission- (0 kg N ha-1), normal urea at 120 kg N ha-1 (recommended dose, N120), and 180 kg N ha-1(N180), Polymer Coated Urea (PCU- 90 kg N ha-1), Urea Briquette-deep placement (UDP- 90 kg N ha-1), GreenSeeker (GS- 143 kg N ha-1) and Leaf Color Chart based N management (LCC- 143 kg N ha-1). N application based on decision support tools (LCC and GS) and innovative fertilizers (UDP, PCU) yielded 17.35-45.81% more grain yield than recommended dose (RDF). The real time nitrogen application through LCC and GreenSeeker and slow release N fertilizer (PCU and UDP) resulted in higher agronomic efficiency of nitrogen- AEN (21.30-27.82 kg grain kg-1 N) compared to RDF (12.15 kg grain kg-1 N) and N180 (19.87 kg grain kg-1 N). UDP, with 25% less N compared to RDF, resulted in higher grain yield (5.25 t ha-1), partial factor productivity of N- PFPN (58.37 kg grain kg-1 N) and AEN (27.82 kg grain kg-1 N). Based on the economic return and ease in the application, both UDP and LCC based N application seem promising in Nepalese conditions. However, their effectiveness should be validated across diverse agro-ecologies, soil types and climatic conditions for a general recommendation.
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We studied the role of biochar in improving soil fertility for maize production. The effects of biochar on the alleviation of three potential physical-chemical soil limitations for maize growth were investigated, i.e. water stress, nutrient stress and acid stress. Experiments involved soils with two dosages of biochar (0.5% and 2% w:w), as well as ones without biochar, in combination with four different dosages of NPK fertilizer, water and lime. Biochar was produced from the invasive shrubby weed Eupatorium adenophorum using flame curtain kilns. This is the first study to alleviate one by one the water stress, nutrient stress and acid stress in order to investigate the mechanisms of biochar effects on soil fertility. Biochar addition increased soil moisture, potassium (K) and plant available phosphorous (P-AL), which all showed significant positive relationship (p<0.001) with above ground biomass of maize. However, biochar was much more effective at abundant soil watering (+311% biomass) than at water-starved conditions (+67% biomass), indicating that biochar did increase soil moisture, but that this was not the main reason for the positive biomass growth effects. Biochar addition did have a stronger effect under nutrient-stressed conditions (+363%) than under abundant nutrient application (+132%). Biochar amendment increased soil pH, but liming and pH had no effect on maize dry biomass, so acidity stress alleviation was not the mechanism of biochar effects on soil fertility. In conclusion, the alleviation of nutrient stress was the probably the main factor contributing to the increased maize biomass production upon biochar addition to this moderately acidic Inceptisol.
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Agricultura/métodos , Carbón Orgánico/química , Fertilizantes , Suelo/química , Zea mays/fisiología , Biomasa , Alimentos , Nepal , Nitrógeno/análisis , Fósforo/análisis , Estrés FisiológicoRESUMEN
Poor water and nutrient retention are the major soil fertility limitations in the low productivity agricultural soils of Nepal. The addition of biochar to these soils is one way these hindrances can be overcome. In the present study, six different biochar doses (control, 5â¯tâ¯ha-1, 10â¯tâ¯ha-1, 15â¯tâ¯ha-1, 25â¯tâ¯ha-1 and 40â¯tâ¯ha-1) were applied to a moderately acidic silty loam soil from Rasuwa, Nepal and the effects on soil physicochemical properties and maize and mustard yield over three years (i.e., six cropping seasons), were investigated. Biochar addition did not show significant effects on maize and mustard grain yield in the first year, however significant positive effects (pâ¯<â¯0.01) were observed during the second and third years. During the second year, maize grain yield significantly increased by 50%, 47% and 93% and mustard grain yield by 96%, 128% and 134% at 15â¯tâ¯ha-1, 25â¯tâ¯ha-1 and 40â¯tâ¯ha-1 of biochar respectively. A similar significant increase in yield of both crops was observed in the third year. Yields for both maize and mustard correlated significantly (pâ¯<â¯0.001) with plant available P, K+, pH, total OC%, CEC, base saturation, and increased as a function of biochar addition. On the basis of the measured crop yields for the various biochar doses, a cost-benefit analysis was carried out, and gross margin was calculated to optimize biochar dose for local farming practice. Total costs included financial cost (farm input, labor and biochar production cost), health cost and methane emission cost during biochar production. Health costs were a minor factor (<2% of total biochar preparation cost), whereas methane emission costs were significant (up to 30% of biochar cost, depending on the C price). Total income comprised sale of crops and carbon sequestration credits. The cost-benefit analysis showed that the optimal biochar application dose was 15â¯tâ¯ha-1 for all C price scenarios, increasing gross margin by 21% and 53%, respectively, for 0 and 42 US$ per ton CO2 price scenarios. In the current situation, only the 0 US$ price scenario is realistic for rural farmers in Nepal, but this still gives benefits of biochar amendment, which are capped at a 15â¯tâ¯ha-1 biochar addition.
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Biochar application to soils has been investigated as a means of improving soil fertility and mitigating climate change through soil carbon sequestration. In the present work, the invasive shrub "Eupatorium adenophorum" was utilized as a sustainable feedstock for making biochar under different pyrolysis conditions in Nepal. Biochar was produced using several different types of kilns; four sub types of flame curtain kilns (deep-cone metal kiln, steel shielded soil pit, conical soil pit and steel small cone), brick-made traditional kiln, traditional earth-mound kiln and top lift up draft (TLUD). The resultant biochars showed consistent pH (9.1 ± 0.3), cation exchange capacities (133 ± 37 cmolc kg-1), organic carbon contents (73.9 ± 6.4%) and surface areas (35 to 215 m2/g) for all kiln types. A pot trial with maize was carried out to investigate the effect on maize biomass production of the biochars made with various kilns, applied at 1% and 4% dosages. Biochars were either pretreated with hot or cold mineral nutrient enrichment (mixing with a nutrient solution before or after cooling down, respectively), or added separately from the same nutrient dosages to the soil. Significantly higher CEC (P< 0.05), lower Al/Ca ratios (P< 0.05), and high OC% (P<0.001) were observed for both dosages of biochar as compared to non-amended control soils. Importantly, the study showed that biochar made by flame curtain kilns resulted in the same agronomic effect as biochar made by the other kilns (P > 0.05). At a dosage of 1% biochar, the hot nutrient-enriched biochar led to significant increases of 153% in above ground biomass production compared to cold nutrient-enriched biochar and 209% compared to biochar added separately from the nutrients. Liquid nutrient enhancement of biochar thus improved fertilizer effectiveness compared to separate application of biochar and fertilizer.
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Carbón Orgánico/química , Carbón Orgánico/farmacología , Productos Agrícolas/efectos de los fármacos , Productos Agrícolas/crecimiento & desarrollo , Suelo/química , Productos Agrícolas/metabolismo , Fertilizantes , Zea mays/efectos de los fármacos , Zea mays/crecimiento & desarrollo , Zea mays/metabolismoRESUMEN
FLAME CURTAIN BIOCHAR KILNS: Pyrolysis of organic waste or woody materials yields charcoal, a stable carbonaceous product that can be used for cooking or mixed into soil, in the latter case often termed "biochar". Traditional kiln technologies for charcoal production are slow and without treatment of the pyrolysis gases, resulting in emissions of gases (mainly methane and carbon monoxide) and aerosols that are both toxic and contribute to greenhouse gas emissions. In retort kilns pyrolysis gases are led back to a combustion chamber. This can reduce emissions substantially, but is costly and consumes a considerable amount of valuable ignition material such as wood during start-up. To overcome these problems, a novel type of technology, the Kon-Tiki flame curtain pyrolysis, is proposed. This technology combines the simplicity of the traditional kiln with the combustion of pyrolysis gases in the flame curtain (similar to retort kilns), also avoiding use of external fuel for start-up. BIOCHAR CHARACTERISTICS: A field study in Nepal using various feedstocks showed char yields of 22 ± 5% on a dry weight basis and 40 ± 11% on a C basis. Biochars with high C contents (76 ± 9%; n = 57), average surface areas (11 to 215 m(2) g(-1)), low EPA16-PAHs (2.3 to 6.6 mg kg(-1)) and high CECs (43 to 217 cmolc/kg)(average for all feedstocks, mainly woody shrubs) were obtained, in compliance with the European Biochar Certificate (EBC). GAS EMISSION FACTORS: Mean emission factors for the flame curtain kilns were (g kg(-1) biochar for all feedstocks); CO2 = 4300 ± 1700, CO = 54 ± 35, non-methane volatile organic compounds (NMVOC) = 6 ± 3, CH4 = 30 ± 60, aerosols (PM10) = 11 ± 15, total products of incomplete combustion (PIC) = 100 ± 83 and NOx = 0.4 ± 0.3. The flame curtain kilns emitted statistically significantly (p<0.05) lower amounts of CO, PIC and NOx than retort and traditional kilns, and higher amounts of CO2. IMPLICATIONS: With benefits such as high quality biochar, low emission, no need for start-up fuel, fast pyrolysis time and, importantly, easy and cheap construction and operation the flame curtain technology represent a promising possibility for sustainable rural biochar production.
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Carbón Orgánico , Contaminantes Atmosféricos , Dióxido de Carbono/análisis , Monóxido de Carbono , Agricultores , Gases/análisis , Metano , Nepal , Suelo/química , Madera/químicaRESUMEN
The effect of HT042, a blend of three herbal extracts, on longitudinal bone growth was investigated in short- and long-term rat models. In the short-term model, we divided female Sprague-Dawley rats (3 weeks old) into six groups, according to treatment: vehicle, HT042 (100 mg/kg), Phlomis umbrosa (100 mg/kg), Astragalus membranaceus (100 mg/kg), and Eleutherococcus senticosus (100 mg/kg) were administered twice daily, and recombinant human growth hormone (rhGH) (1 IU) was subcutaneously injected once daily. Treatments were maintained for 4 days in each case. On day 3, tetracycline (20 mg/kg) was injected intraperitoneally (20 mg/kg) to form the fluorescent band on the growth plates. On days 2-4, 5-bromo-2'-deoxyuridine (BrdU) (50 mg/kg) was injected intraperitoneally to label proliferating cells. On day 5, the tibias were dissected and fixed in 30% sucrose. Dehydrated bone was sectioned at a thickness of 40 µm and observed. The bone growth in groups administered HT042 and rhGH was significantly increased to 433.50 ± 21.61 and 434.49 ± 15.21 µm/day, respectively, from 410.03 ± 17.4 µm/day (control). The height of the growth plates in the HT042 and rhGH groups was also significantly increased to 556.5 ± 21.1 and 544.2 ± 21.1 µm (P < .05), respectively, from 518.1 ± 4.1 µm (normal). The number of BrdU-positive cells in chondrocytes of the HT042 and rhGH groups was increased to 389 ± 36 and 627 ± 39 cells/mm² (P < .001), respectively, from 264 ± 17 cells/mm² (control). Insulin-like growth factor-1 and bone morphogenetic protein-2 in the HT042 group were highly expressed in the growth plate. In the long-term rat model, the body weight, nose-tail length, and nose-anus length were measured by microknemometry for 4 weeks. The body weight of the rhGH group was significantly increased. The nose-anus length of the HT042 and rhGH groups was significantly greater at 18.5 ± 0.3 and 18.7 ± 0.3 cm compared to 18.2 ± 0.2 cm (control).
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Desarrollo Óseo/efectos de los fármacos , Preparaciones de Plantas/uso terapéutico , Tibia/efectos de los fármacos , Tibia/crecimiento & desarrollo , Animales , Astragalus propinquus/química , Tamaño Corporal/efectos de los fármacos , Proteína Morfogenética Ósea 2/metabolismo , Recuento de Células , Condrocitos/citología , Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Eleutherococcus/química , Femenino , Trastornos del Crecimiento/tratamiento farmacológico , Placa de Crecimiento/citología , Placa de Crecimiento/efectos de los fármacos , Placa de Crecimiento/crecimiento & desarrollo , Placa de Crecimiento/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Medicina Tradicional Coreana , Osteogénesis/efectos de los fármacos , Phlomis/química , Fitoterapia , Preparaciones de Plantas/química , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Tibia/citología , Tibia/metabolismoRESUMEN
Sesame (Sesamum indicum L.) is an important oilseed crop that possesses a wide spectrum of pharmacological activities. Many studies have been conducted to investigate its health-promoting effects. Compared to other plant oils, sesame seed oil is highly stable to oxidation and has been demonstrated to have protective effects against ischemia-reperfusion injury in the rat brain. However; the effects of defatted sesame seeds extract (DSE) have not been studied yet. The purpose of this study was to evaluate the protective effect of DSE against ischemia models. For in vitro ischemia, oxygen-glucose deprivation followed by reoxygenation (OGD-R, 4 h OGD followed by 24 h reoxygenation) in HT22 cells was used to investigate the protective effects on cell death and the inhibitory effects on lipid peroxidation. For in vivo ischemia, the middle cerebral artery occlusion (MCAo, 2 h of MCAo followed by 22 h of reperfusion) rat model was used. Twenty-two h after occlusion the rats were assessed for neurobehavioral deficit and infarct volume. DSE (0.1-10 microg/mL) significantly reduced the cell death and inhibited lipid peroxidation induced by OGD-R. DSE (30, 100 and 300 mg/kg, p.o.) given twice at 0 h and 2 h after onset of ischemia reduced brain infarct volume dose-dependently and improved sensory-motor function. The therapeutic time window of DSE (300 mg/kg, p.o.) was 2 h after MCAo in rats. In conclusion, our results show that DSE may be effective in ischemia models by an antioxidative mechanism.