Combined Application Of Biochar Research Articles

Modulation of drought adversities in Vicia faba by the application of plant growth promoting rhizobacteria and biochar.

Drought is the greatest threat to world food security, seen as the catalyst for the great famines of the past. Given that the world's water supply is limited, it is likely that future demand of food for increasing population will further exacerbate the drought effects. Therefore, the present study was aimed to investigate the effect of biochar and plant growth promoting rhizobacteria (PGPR) Sphingobacterium pakistanensis (NCCP246) and Cellulomonas pakistanensis (NCCP11) on agronomic and physiological attributes of Vicia faba two varieties Desi (V1) and Pulista (V2) under induced drought stress. The seeds were sown in earthen pots filled with 3kg sand and soil (1:2), and biochar (0 and 5% w/w) in triplicate arranged in complete randomized design. Analysis of biochar possessed 0.49 g cm-3 bulk density, 9.6 pH; 5.4 cmol kg-1 cation exchange capacity, 3.64% organic carbon and EC 6.7 ds/m. Agronomic attributes including seed LAI, LAR, SVI, %PHSI and RWC were improved by 30.4-180.4%, 14.37-47.20%, 37.64-50.91%, 18.21-30.80, and 35.82-54.34% in both varieties by the co-application of biochar and PGPR. Stomatal physiology and epidermal vigor was successfully improved by the application of PGPR and biochar as analyzed by scanning electron microscopy (SEM). Photosynthetic pigments, flavonoids, phenols, proline and glycine betaine were amplified by 58.33-173.8%, 50.59-130.33%, 46.58-86.62%, 46.66-109.30%, 35.74-56.10%, and 21.96-77.22% in both varieties by the co-application of biochar and PGPR. So, the present work concluded that, combined application of biochar and PGPR could be an effective strategy to alleviate the adversities of drought in V. faba growing in drastic ecosystems.

Selenium treated foliage and biochar treated soil for improved lettuce (Lactuca sativa L.) growth in Cd-polluted soil

Cadmium (Cd) pollution in farmland soils is a serious concern due to its devastating effects on living organisms. This requires developing effective strategies to inhibit the Cd absorption and accumulation by vegetables. In this study, the influence of soil applied biochar (BC) (10 and 30 g kg−1) and foliage applied selenium (Se) fertilizer (1 and 3 mg L−1) on the absorption and accumulation of Cd and growth of lettuce under Cd stress (1 and 3 mg/kg) was evaluated. In Cd-contaminated soil, the application of BC and Se significantly increased lettuce biomass and chlorophyll contents by 74% and 100%, respectively, compared to control in lettuce. The combined application of BC and Se at (B 30 g kg−1, Se 3 mg L−1) was effective in reducing the accumulation of Cd by lettuce shoot by 73.41% than control. Co-application of BC and Se enhanced the activities of antioxidant enzymes catalase, superoxide dismutase by 77 and 96%, respectively, and reduced the malondialdehyde contents by 56% than control. Application of biochar (30 g kg−1) significantly increased the soil electrical conductivity and soil organic carbon of soil by 48 and 41%, respectively as compared to control. The combination of BC and Se (B 30 g kg−1, Se 3 mg L−1) reduced the Cd contents in lettuce shoots from 0.79 mg kg−1 to 0.08 mg kg−1 below the national food safety standard threshold (0.2 mg kg−1 Cd). Overall, this study revealed that the integrated application of BC (30 g kg−1) and Se (3 mg L−1) can help prevent the absorption of Cd by lettuce. However, the effectiveness of BC in remediating trace metals may decrease with time due to the aging factor and leaching alkalinity of BC, so long-term field experiments are needed to enhance the understanding of BC efficiency and an appropriate Se concentration for specific green soil remediation goals.

Co-Application of Biochar and Arbuscular mycorrhizal Fungi Improves Salinity Tolerance, Growth and Lipid Metabolism of Maize (Zea mays L.) in an Alkaline Soil.

This study reports the mitigating strategy against salinity by exploring the potential effects of biochar (5%), Arbuscular mycorrhizal fungi (20 g/pot, AMF), and biochar + AMF on maize (Zea mays L.) plants grown under saline stress in a greenhouse. The maize was grown on alkaline soil and subjected to four different saline levels; 0, 50, 100, and 150 mM NaCl. After 90 d for 100 mM NaCl treatment, the plant’s height and fresh weight were reduced by 17.84% and 39.28%, respectively, compared to the control. When the saline-treated soil (100 mM NaCl) was amended with AMF, biochar, and biochar + AMF, the growth parameters were increased by 22.04%, 26.97%, 30.92% (height) and 24.79%, 62.36%, and 107.7% (fresh weight), respectively. Compared to the control and single AMF/biochar treatments, the combined application of biochar and AMF showed the most significant effect in improving maize growth under saline stress. The superior mitigating effect of biochar + AMF was attributed to its effective ability in (i) improving soil nutrient content, (ii) enhancing plant nutrient uptake, (iii) increasing the activities of antioxidant enzymes, and (iv improving the contents of palmitoleic acid (C16:1), oleic acid (C18:1), linoleic acid (C18:2), and linolenic acid (C18:3). Thus, our study shows that amending alkaline and saline soils with a combination of biochar-AMF can effectively mitigate abiotic stress and improve plant growth. Therefore, it can serve as a reference for managing salinity stress in agricultural soils.

The Combined Effect of Pseudomonas stutzeri and Biochar on the Growth Dynamics and Tolerance of Lettuce Plants (Lactuca sativa) to Cadmium Stress

Agricultural activities lead to the accumulation of cadmium (Cd) in the soil. It is necessary to identify effective and economical ways to reduce the soil Cd bioavailability. To achieve this, three bacterial strains, Pseudomonas stutzeri, P. koreensis, and P. fluorescens, were tested for tolerance and biosorption of different concentrations of Cd (0, 5, 10, 15, 20, and 25 mg L−1). During the 2020 and 2021 seasons, a pot experiment was conducted using four different soil amendments (control, biochar, P. stutzeri, and a combination) under four levels of Cd (0, 40, 80, and 120 mg kg−1) and assessing the effect on growth parameters, physiological modifications, antioxidant enzymes, and Cd accumulation in lettuce plants (Lactuca sativa cv. Balady). In vitro, the results showed that P. stutzeri was the most tolerant of Cd. Our findings in pot trials showed that T4 (biochar + P. stutzeri) was a more efficient treatment in terms of the growth parameters, with 452.00 g plant−1 was recorded for fresh weight, 40.10 g plant−1 for dry weight, 18.89 cm plant−1 for plant height, 6.03 cm2 for leaf area, and 20.48 for the number of leaves plant−1, while in terms of physiological characteristics, we recorded 1.29 mg g−1 FW, 0.35 μg g−1 FW, and 3.69 μg g−1 FW for total chlorophyll, carotenoids, and total soluble sugar, respectively; this was also reflected in the number of antioxidant enzymes and intensity of soil biological activities in soil treated with 120 mg kg−1 Cd compared with the control and other treatments in the first season. A similar trend was observed in the second season. Additionally, significantly lower Cd was observed in both the root (67%) and shoots (78%). Therefore, a combined application of biochar and P. stutzeri could be used as an alternative to mitigate Cd toxicity.

Ammonia- and Nitrite-Oxidizing Bacteria are Dominant in Nitrification of Maize Rhizosphere Soil Following Combined Application of Biochar and Chemical Fertilizer.

Autotrophic nitrification is regulated by canonical ammonia-oxidizing archaea (AOA) and bacteria (AOB) and nitrite-oxidizing bacteria (NOB). To date, most studies have focused on the role of canonical ammonia oxidizers in nitrification while neglecting the NOB. In order to understand the impacts of combined biochar and chemical fertilizer addition on nitrification and associated nitrifiers in plant rhizosphere soil, we collected rhizosphere soil from a maize field under four different treatments: no fertilization (CK), biochar (B), chemical nitrogen (N) + phosphorus (P) + potassium (K) fertilizers (NPK), and biochar + NPK fertilizers (B + NPK). The potential nitrification rate (PNR), community abundances, and structures of AOA, AOB, complete ammonia-oxidizing bacteria (Comammox Nitrospira clade A), and Nitrobacter- and Nitrospira-like NOB were measured. Biochar and/or NPK additions increased soil pH and nutrient contents in rhizosphere soil. B, NPK, and B + NPK treatments significantly stimulated PNR and abundances of AOB, Comammox, and Nitrobacter- and Nitrospira-like NOB, with the highest values observed in the B + NPK treatment. Pearson correlation and random forest analyses predicted more importance of AOB, Comammox Nitrospira clade A, and Nitrobacter- and Nitrospira-like NOB abundances over AOA on PNR. Biochar and/or NPK additions strongly altered whole nitrifying community structures. Redundancy analysis (RDA) showed that nitrifying community structures were significantly affected by pH and nutrient contents. This research shows that combined application of biochar and NPK fertilizer has a positive effect on improving soil nitrification by affecting communities of AOB and NOB in rhizosphere soil. These new revelations, especially as they related to understudied NOB, can be used to increase efficiency of agricultural land and resource management.

Compensation of high nitrogen toxicity and nitrogen deficiency with biochar amendment through enhancement of soil fertility and nitrogen use efficiency promoted rice growth and yield

AbstractThe quality and nutritional status of agricultural soils are depleting gradually, and biochar is widely used in soil quality improvement. A sustainable approach of biochar application needs a better understanding of its interaction with nitrogen application and the final effect on crop growth. In our study, the effect of different biochar application levels (0, 15, 30, and 60 tons ha−1) in combination with nitrogen fertilizer levels (0, 150, 300, and 450 kg ha−1) on soil properties, rice growth, and nitrogen use efficiency were investigated. The results showed that sole application of biochar (B60) did not promote the rice growth except the soil organic carbon (SOC), total nitrogen, total phosphorous, and available potassium compared with no biochar addition, while a single application of 450 kg N ha−1 (N450) adversely affected the rice physiological and yield traits by destroying rice leaf ultrastructure and reducing the stomatal length by 13%, stomatal width 3% and density 12%, plant height 5%, dry biomass plant−1 4%, spike weight plant−1 8%, and grain weight plant−1 9% compared to N300 unless it was treated in combination with biochar. Biochar can significantly compensate the toxicity of excessive nitrogen and deficiency of low nitrogen fertilizer on rice growth. Compared to a single application of B0+N450 (450 kg N ha−1), combined application of biochar and nitrogen B30+N450 could elevate rice plant nitrogen content by 13%, plant height 30%, aboveground dry biomass plant−1 136%, spike weight plant−1 34%, and grain weight plant−1 36% while increments in total nitrogen accumulation (TNA 79%%) and nitrogen use efficiency (NUE 35%) were noted in B30+N300 treatment. These results suggest that biochar amendment combined with a proper amount of nitrogen fertilizer is an effective approach to promote soil conditions, manage nitrogen utilization, improve plant growth and increase crop yield on a sustainable basis.

Biochar promotes soil organic carbon sequestration and reduces net global warming potential in apple orchard: A two-year study in the Loess Plateau of China

The Loess Plateau is China's primary apple-growing area, and the orchard is a significant source of greenhouse gases (GHGs) emissions due to high nitrogen fertilizer input. Thus, a two-year field study was carried out to investigate the effects of apple wood derived biochar on GHGs emissions during apple orchard production, including soil organic carbon sequestration (SOCSR) and net global warming potential (NGWP) assessments. There are four treatments in this study: 20 t ha−1 biochar in a non-fertilized plot (B); no biochar in a fertilized plot (F); 20 t ha−1 biochar in a fertilized plot (FB); no biochar in a non-fertilized plot (CK). Results showed that the combined application of biochar and fertilizer stimulated CO2 emissions by 9.25% and 8.39% than either biochar or fertilizer alone. Meanwhile, biochar in fertilized plot increased annual N2O emissions by 32.6% as compared to fertilized plot without biochar amendment. Compared with CK, biochar had no significant effect on GHG emissions in unfertilized plot. The N2O emission factor of FB and F were 0.91% and 0.45% respectively in 2017–2018 and they were both 0.34% in 2018–2019. Moreover, compared with CK, the FB and B treatments increased the SOCSR by 316.52% and 354.78%, while, decreased the NGWP by 368.93% and 480.91%, respectively. Thus, biochar application may help reduce the impact of apple production on climate change by sequestering more soil organic carbon and decreasing the NGWP.

Poultry litter biochar application in combination with chemical fertilizer and Azolla green manure improves rice grain yield and nitrogen use efficiency in paddy soil

Poultry litter biochar application in combination with chemical fertilizer and Azolla green manure improves rice grain yield and nitrogen use efficiency in paddy soil

Biochar and earthworms synergistically improve soil structure, microbial abundance, activities and pyraclostrobin degradation

As a widely used fungicide, the toxic impacts of pyraclostrobin on soil ecosystems have attracted extensive concern. Thus, it is very important and meaningful to develop effective strategies to alleviate its toxic effects. Therefore, in this study, we used corn straw-derived biochar produced at 500 °C as a soil amendment to study its effects on soil microbial populations, aggregation, enzymatic activities, and earthworm Eisenia fetida in pyraclostrobin-contaminated soil. Our results showed that biochar application (1%, w/w) significantly (Tukey test, p < 0.05) increased microbial abundance (culturable fungi, bacteria, actinomycetes), enzyme activities (urease, invertase, and dehydrogenase), and the formation of soil macroaggregates (>0.25 mm). Moreover, biochar application eliminated the toxic effects of pyraclostrobin on soil microorganisms and reduced oxidative stress and DNA damage in E. fetida by increasing the dissipation of pyraclostrobin in soil. We also found that biochar and earthworms synergistically improved the soil structure and degradation of pyraclostrobin, thus indicating that the combined application of biochar and earthworms is a better strategy to improve soil physical structure, biological properties, and health. Finally, we conclude that increasing the soil food web and physical complexity by adding biochar and earthworms may improve soil health stressed by xenobiotic pollutants.

Biochar-N fertilizer interaction increases N utilization efficiency by modifying soil C/N component under N fertilizer deep placement modes

The situation of imbalance application of nitrogenous fertilizers in maize production is a serious issue in China, and excessive nitrogen (N) application is hazardous to sustainable agricultural production and environment. In this experiment, two biochar levels (C0: 0, C1: 2 %), three different N rates (N1: 50, N2: 100, and N3: 200 mg kg−1), and two fertilization methods (T: traditional N fertilizer application mode and D: deep N fertilizer placement mode) were set up to study the response of different treatments on maize yield, N uptake, and N use efficiency. Herein, we found that fresh and dry biomasses were increased by 292 % and 283 % under C1N3 treatment with the deep application of N fertilizer compared to the control treatment (without nitrogen fertilizers and biochar). According to structural equation modeling (SEM), soil physical and chemical properties, N component and C component in different soil layers were associated with biochar and N fertilizer treatment, especially at 20–40 depth. The combination of N fertilizer and biochar application promoted the effects of biochar on the improving NUE of plants. The biochar alleviated the loss of soil nitrogen (from 52.00 to 25.94 %) under traditional N fertilizer application. Overall, excessive input of N fertilizer not only promotes the growth of crops but also causes a waste of resources and environmental pollution. We suggest that combined application of biochar and N fertilizer could significantly reduce N loss, and improve root growth and N uptake, resulting in improving NUE by improving soil environment (pH, SOM, EC) and adjusting soil C/N component.

Effect of Biochar Application in Combination with Different Nutrient Sources on Cauliflower Production at Kaski Nepal

Field experiments were conducted during the winter season of 2016/17 and 2017/18 to assess the effect of biochar application in combination with different nutrient sources on cauliflower (Brassica oleraceae var. botrytis) production in sandy loam soil. The experiment was conducted using a Randomized Complete Block Design (RCBD) with ten different treatment viz., Farmer’s practice as control treatment, Recommended dose of fertilizer (200:120:80 kg NPK/ha), Composted biochar @ 1t/ha, Urine Soaked biochar @ 1t/ha, Mineral fertilizer (200:120:80 kg NPK/ha) mixed biochar @ 1t/ha, Humic acid soaked biochar @ 1 t/ha, Composted biochar @ 2t/ha, Urine Soaked biochar @ 2t/ha, Mineral fertilizer (200:120:80 kg NPK/ha) mixed biochar @ 2t/ha and Humic acid soaked biochar @ 2 t/ha, each replicated for three times. The application of biochar in combination with mineral fertilizers significantly increased the yields of cauliflower in both consecutive years. Application of biochar @ 2 t/ha along with mineral fertilizer at recommended dose increased curd yield of cauliflower by 37 % compared to that of only mineral fertilizer application and by 59 % compared to that of control treatment. Biochar and inorganic sources of nutrition together in soil showed superiority over other practices and would be of immense value to increase the productivity of cauliflower.

Effects of Mixed Application of Wood Vinegar and Biochar on Cadmium Absorption of Pakchoi under Different Concentrations of Cadmium Stress

Because of its characteristics, wood vinegar is widely used in agricultural production processes. Wood vinegar can be used as a strong antioxidant, anti-bacteria, plant growth agent, an insecticide, and currently shows superiority in the treatment of heavy metals. Wood vinegar contains organic acids, organic compounds, and phenol, which can effectively adsorb heavy metals. A large number of studies have been conducted on the adsorption of heavy metals by biochar, but few studies have analyzed the effects of biochar and wood vinegar fertilization on the growth of cadmium soil genus plants and changes in soil heavy metal forms. This article analyzed the effects of wood vinegar and biochar mixed fertilizer on the growth and plant efficacy of pakchoi from the properties of wood vinegar, and confirmed that 0.75% wood vinegar liquid treatment is the most effective concentration. By analyzing the effectiveness of 0.75% wood vinegar and biochar mixture and single fertilization, the combined application of biochar + wood vinegar reduced the absorption rate of cadmium by pakchoi leaves and roots by 12.8% and 13.1% compared with the single treatment group. The yield of crops increased by 111.9~150.1%. The results of evaluating the enrichment coefficient and single-factor index are 0.17~0.67%, 0.005-0.008, and the ranking is D&gt; E&gt; C&gt; B&gt; A&gt; CK. When observing the changes in soil morphology, the content of residual cadmium, carbonate-bound cadmium, and iron-manganese oxide-bound cadmium increased by 0.3~233.7 times, and the exchangeable cadmium content and the content of organic and sulfide-bound cadmium were reduced to 1.0~6.6 times. It can be seen that under different cadmium stress conditions, the mixed fertilization of wood vinegar and biochar will reduce the growth of pakchoi and the plant availability of cadmium, and it has a higher mitigation effect on cadmium soil pollution.

Effect of Different Organic Sources on Physical, Chemical and Biological Properties of Soil in Inceptisols of Varanasi

After the green revolution excessive use of inorganic fertilizers increased, which resulted in affecting the activities of soil microflora and macrofauna, thus posing an environmental risk and decreasing crop production. The use of organic sources which include biochar, carpet waste, FYM (Farmyard manure) and PGPR (Plant growth promoting rhizobacteria) may act as an important tool to sustainably increase soil organic matter, crop yield and improve soil health on a long-term basis. The results of application of biochar, carpet waste, farm yard manure (FYM) and PGPR showed that the combined application of biochar, carpet waste and PGPR significantly improved soil properties such as organic carbon, nitrogen(N), phosphorus(P), potassium(K), dehydrogenase, alkaline phosphatase activity and microbial population. The enzymatic activity of soil was highly positively correlated with the physicochemical properties of soil. Therefore, it can be concluded that the combination of biochar, carpet waste, FYM and PGPR may increase and sustain the soil properties and crop productivity over time.

Co-application of high temperature biochar with 3,4-dimethylpyrazole-phosphate treated ammonium sulphate improves nitrogen use efficiency in maize

This study aimed on the increasing nitrogen use efficiency (NUE) of maize via the use of high temperature produced biochar (700 °C). Maize was grown to maturity on two contrasting soils (acidic Cambisol and neutral Chernozem) in pots with a treatment of biochar co-applied with ammonium sulphate stabilised by a nitrification inhibitor (3,4-dimethylpyrazole-phosphate, DMPP) or un-stabilised. The combination of biochar with ammonium sulphate containing DMPP increased maize biomass yield up to 14%, N uptake up to 34% and NUE up to 13.7% compared to the sole application of ammonium sulphate containing DMPP. However, the combination of biochar with un-stabilised ammonium sulphate (without DMPP) had a soil-specific influence and increased maize biomass only by 3.8%, N uptake by 27% and NUE by 11% only in acidic Cambisol. Further, the biochar was able to increase the uptake of phosphorus (P) and potassium (K) in both stabilised and un-stabilised treatments of ammonium sulphate. Generally, this study demonstrated a superior effect from the combined application of biochar with ammonium sulphate containing DMPP, which improved NUE, uptake of P, K and increased maize biomass yield. Such a combination may lead to higher efficiency of fertilisation practices and reduce the amount of N fertiliser to be applied.

Impact of N-fertilization and peanut shell biochar on soil microbial community structure and enzyme activities in a Typic Haplustoll under different management practices

The application of biochar with N-fertilizer is one of the most attractive practices for increasing soil quality and fertility. However, few studies have examined the combined effects of peanut biochar and urea on soil microbial community structure and function. Phospholipid fatty acid (PLFA) analysis and various enzyme activities were used to monitor microbial community structure and function in a 20-week incubation experiment. Different rates of biochar (0, 1, and 3% dry wt. soil) and N-fertilizers (with or without urea addition at 0.2 g kg−1) were applied to a Typic Haplustoll under conventional (CV) and conservation (CS) land management practices. A pristine forest soil (CK) was also included as control. Overall, the lowest microbial activity and abundance of microbial PLFA bioindicators were recorded under CV, confirming that conservation management may improve soil quality. Our study also indicated that the effect of biochar and management practices on the microbial community structure was more significant than that of urea. Particularly under both CS and CK, biochar tended to increase glucosidase, glucuronidase, and phosphomonoesterase activities, being on average 65%, 43%, and 85% significantly higher in biochar 3% than in the control treatment, respectively. Thus, we found a strong correlation between soil macronutrients and enzymes such as glucosidase and urease. Although total PLFA content was poorly affected, biochar addition increased some individual PLFA biomarkers, suggesting that both the biochar rates (1% and 3%) may increase Gram-negative bacteria and fungal populations. Regardless of biochar addition, urea application significantly increased urease activity. We also found a positive correlation between fungal PLFAs (VAM and total fungi) and urease activity, indicating that biochar tended to increase fungal biomass. The combined application of biochar and urea to soil under appropriate management may thus be a feasible and effective strategy for improving soil microbial quality.

Transforming a Valuable Bioresource to Biochar, Its Environmental Importance, and Potential Applications in Boosting Circular Bioeconomy While Promoting Sustainable Agriculture

Biochar produced from transforming bioresource waste can benefit sustainable agriculture and support circular bioeconomy. The objective of this study was to evaluate the effect of the application of biochar, produced from wheat straws, and a nitrification inhibitor, sourced from neem (Azadirachta indica), in combinition with the recommended synthetic fertilizer on soil properties, maize (Zea mays L.) plant growth characteristics, and maize grain yield and quality paramters. The nitrification inhibitor was used with the concentrations of 5 and 10 mL pot−1 (N1 and N2, respectively) with four levels of biochar (B0 = 0 g, B1 = 35 g, B2 = 70 g, B3 = 105 g, B4 = 140 g pot−1), one recommended nitrogen, phosphorous, and potassium syntactic fertilizer (250, 125, and 100 kg ha−1, respectively) treatment, and one control treatment. The results showed that the nitrification inhibitor enhanced crop growth while the application of biochar significantly improved soil fertility. The application of biochar significantly enhanced soil organic matter and soil nitrogen as compared with nitrogen–phosphorus–potassium treatment. The highest root length (65.43 cm) and root weight (50.25 g) were observed in the maize plants treated with B4 and N2 combinedly. The grain yield, total biomass production, protein content from biochar’s B4, and nitrogen–phosphorus–potassium treatments were not significantly different from each other. The application of 140 g biochar pot−1 (B4) with nitrification inhibitor (10 mL pot−1) resulted in higher crop yield and the highest protein contents in maize grains as compared to the control treatments. Therefore, the potential of biochar application in combination with nitrification inhibitor may be used as the best nutrient management practice after verifying these findings at a large-scale field study. Based on the experimental findings, the applied potential of the study treatments, and results of economic analysis, it can be said that biochar has an important role to play in the circular bioeconomy.

Cumulative effect of biochar and compost on nutritional profile of soil and maize productivity

Organic amendments of soil have the ability to enhance crop production and influence soil health by altering its physical and chemical properties. However, studies are limited regarding field evaluation of biochar and compost influence on crop yield and soil health. Therefore, the present study was planned to evaluate the beneficial impact of biochar together with compost on nutritional profile of soil and maize productivity. Cow manure was used as a biomass to prepare biochar and compost. For biochar production the pyrolysis temperature was kept at 480 °C. The experiment comprised of four treatments: (1) Control (2) Biochar (3) Compost, and (4) Biochar + Compost, at the rate of 5 tons ha−1, for each. There was an increase of 46.29% and 13.4% in grain yield and biological yield, respectively, in treatment containing biochar and compost over un-treated control. Similarly, the soil organic carbon has also shown an increase of 80.52% due to the synergistic effect of biochar and compost. However, there was a decline in soil pH by combined application of biochar and compost. Conclusively, biochar and compost have the potential to increase crop productivity with better management of soil nutrients and properties.

Efectividad de biochar y biofertilizantes en el crecimiento y calidad de plántulas de cacao

El objetivo principal de la investigación fue evaluar la efectividad de biochar y biofertilizantes en el crecimiento y calidad de plántulas de cacao en vivero. El trabajo se desarrolló desde enero a abril del 2020, en casa de cultivos del Instituto Superior Tecnológico Calazacón en Santo Domingo de los Tsáchilas, Ecuador. Los tratamientos evaluados fueron T1: biochar, T2: biochar + biofertilizante, T3: biofertilizante, T4: fertilizante compuesto y T5: tratamiento control. El biochar fue aplicado en dosis de 20 g kg-1 de sustrato. El biofertilizante se conformó de un consorcio microbiano comercial compuesto por cepas de hongos, bacterias, micorrizas y levaduras. Se utilizó un diseño completamente al azar con cuatro replicas. La unidad experimental se conformó de 20 plántulas de cacao CCN-51. Las principales variables registradas fueron masa seca de planta (g), área foliar (cm2) e índice de calidad de Dickson. Los resultados mostraron diferencias estadísticas significativas (p &lt; 0.05) entre los tratamientos evaluados, destacándose el tratamiento de biochar + biofertilizante con la mayor tasa de crecimiento en masa seca, área foliar e índice calidad de Dickson con 8.23 g, 497.82 cm2 y 5.45, respectivamente, en relación a los demás tratamientos evaluados. Se encontró una correlación significativa (p &lt; 0.05) y positiva entre el índice de calidad de Dickson y las variables de crecimiento analizadas. La aplicación combinada de biochar y biofertilizantes en los sustratos puede potenciar el crecimiento y calidad de plántulas de cacao en vivero.

Efficacy of using biochar, phosphorous and nitrogen fertilizers for improving maize yield and nitrogen use efficiencies under alkali clay soil

Various responses of plant growth attributes to the combined application of biochar and mineral fertilizers were reported according to trial conditions. Thus we studied the effects of biochar combined with nitrogen and phosphorous fertilizers on crop growth and yield and NUE of maize crop under alkali clay soil. Field trial during two successive seasons (2018 and 2019) was conducted to investigate the possibility of biochar addition (0, 6 and 12 Mg ha−1), as well as, P (0 and 37 kg P2O5 ha−1) and N (95, 190 and 285 kg N ha−1) fertilizations on maize and some nitrogen use efficiencies attributes. The results revealed that, biochar addition at 6 or 12 Mg ha−1 resulted in a significant reduction in plant height, stem diameter and ear length compared with the control treatment. In contrast, biochar applied recorded significant increase in both leaves area per plant, grain yield and yield attributes, as well as, grain protein content, NUE, grain-NUtE, as well as, total-NUpE compared by control treatment. Applying 190 kg N ha−1 caused significant increase in each of growth and grain yield attributes, as well as, grain-NUtE. Biochar addition by 6 or 12 Mg ha−1 combined with P (37 kg P2O5 ha−1) and N (190 or 285 kg N ha−1) application had the greater effect on increasing stem diameter, ear length, almost yield attributes, NUE, as well as, grain-NUtE. However, NUE and total-NUpE showed negative response to biochar added with N fertilizer.

Impact of biochar on nutrient uptake by tomato, residual soil properties and acidity indices in acid Inceptisol of Meghalaya

Aim: To investigate the impact of biochar as component of integrated nutrient management on nutrient uptake by tomato in acid soil of Meghalaya, North East India. Methodology: A field experiment was conducted at research farm of SNRM, College of Post Graduate Studies in Agricultural Sciences (CPGS-AS), Central Agricultural University (CAU-I), Umiam during rabi 2017-18 taking tomato, cv. Megha Tomato-2 as test crop. Sixteen treatment combinations of recommended closes of fertilizers, biochar and vermicompost? were tested in RBD with three replications.? Results: The experimental results revealed that combined application of biochar, fertilizers and vermicompost increased the uptake and availableof N, P, K, Fe, Zn, Mn and Cu over graded doses of biochar + fertilizers, biochar alone and control. Electrical conductivity, bulk density, exchangeable acidity, exchangeable aluminium and acid saturation followed the same trend.? Interpretation: The 100% RDF + biochar 4 t ha-1 + vermicompost @ 2.5 t ha-1 is the most appropriate combination for increasing tomato productivity and improving soil health of acidic soil in Meghalaya.