Enhance Soil Fertility Research Articles

Mixing with Schima Superba Enhanced Soil Fertility and Simplified Soil Microbial Community of Eucalyptus Urophylla Forests

Mixing with Schima Superba Enhanced Soil Fertility and Simplified Soil Microbial Community of Eucalyptus Urophylla Forests

Dairy effluent applications to a pasture enhance soil fertility and microbial activity without impacting soil bacterial and fungal community composition

Farm dairy effluents (FDE) from washing the milking parlor contain manure, urine, and chemicals and constitute a large amount of wastewater. Applying FDE as soil fertilizers to pastures can enhance forage yield and improve soil nutrient status. Since the dairy industry is increasingly attempting to maximize returns through better utilization of forage with lesser inputs, there is demand for a supply of FDE as fertilizers. Nevertheless, the impact of this practice on soil microbiota remains largely unexplored. It must be studied before large-scale soil disposal to avoid diminishing microbial diversity or enhancing pathogen abundance. This study evaluated the effects of applying lagoon-stored (Lagoon) and raw dairy effluents (Raw) at a rate of 50 kg N ha−1 in four equal doses, in comparison to urea fertilization, on soil fertility and the activity, abundance, and community structure of soil microbiota. Raw was obtained after solid separation, and Lagoon corresponds to the Raw stationed in a two-lagoon system. Microbial activity was assessed as basal respiration, potentially mineralizable N, potential nitrification activity, and enzymatic activities. The catabolic activity of the microbial community was evaluated using Biolog Ecoplates™. Bacterial and fungal community composition and diversity were analyzed through amplicon sequencing of 16S rRNA and ITS2. The application of FDE benefited soil fertility and microbial activity. Lagoon had the most potent effects on soil available P and extractable K+, Na+, Mg2+ and Ca2+. Soil treated with Raw displayed higher microbial activities, such as dehydrogenase, basal respiration, urease, and potentially mineralizable N, than the other treatments. FDE did not significantly alter the microbial composition, abundance, or functional diversity. In conclusion, in this short-term trial, despite changes in soil chemical properties and microbial activity, the composition and diversity of the bacterial and fungal communities remained unaffected by FDE irrigation.

Partial Substitution of Nitrogen Fertilizer with Biogas Slurry Increases Rice Yield and Fertilizer Utilization Efficiency, Enhancing Soil Fertility in the Chaohu Lake Basin.

To investigate the effects of biogas slurry substitution for fertilizer on rice yield, fertilizer utilization efficiency, and soil fertility, a field experiment was conducted on rice-wheat rotation soil in the Chaohu Lake Basin for two consecutive years, with the following six treatments: no fertilization (CK), conventional fertilization (CF), optimized fertilization (OF), biogas slurry replacing 15% of fertilizer (15% OFB), biogas slurry replacing 30% of fertilizer (30% OFB), and biogas slurry replacing 50% of fertilizer (50% OFB). The field experiment results showed that, compared with CF treatment, OF treatment in 2022 and 2023 significantly increased (p < 0.05) rice yield, promoted the uptake of nitrogen (N), phosphorus (P), and potassium (K) by grains and straws, improved fertilizer utilization efficiency, and increased the contents of soil organic C (SOC), NH4+-N, NO3--N, hydrolysable N, and available P. The 15% OFB and 30% OFB treatments significantly increased (p < 0.05) rice grain and straw yields compared with CF treatment, and rice grain and straw yields were the highest in the 30% OFB treatment. Compared with CF and OF treatments, 30% OFB treatment significantly increased (p < 0.05) the N, P, and K uptake of grains and straws and increased the fertilizer utilization efficiency. Compared with CF treatment, the grain yield of 50% OFB treatment was significantly decreased (p < 0.05) in 2022, and there was no significant difference in 2023, which may be because the biogas slurry was applied before planting in 2023 to provide more nutrients for early rice growth. Compared with CF treatment, 30% OFB treatment significantly increased (p < 0.05) the contents of SOC, NH4+-N, available K, and hydrolysable N. In summary, optimizing N and K topdressing methods can increase rice yield and improve the fertilizer utilization efficiency and soil fertility. The 30% OFB treatment resulted in the highest rice yield, fertilizer utilization efficiency, and improved soil fertility, indicating that biogas slurry replacing 30% of fertilizer was the best application mode for rice in this region.

Productivity and health of soil cultivated with forage cactus (Opuntia cochenillifera (L.) Mill.) with combined use of topsoil and biochar

Agricultural production in semi-arid environments represents a significant challenge, as these are areas that have soils with limited nutrient availability and scarcity of precipitation, which require adaptive and innovative strategies. The application of biochar to improve soil quality and increase productivity has been well studied. However, there is still a gap regarding the use of biochar with the technique of incorporating different topsoils on plant development and soil health. This technique has emerged as an alternative for producers to increase soil fertility. This technique is emerging as an alternative for producers to enhance soil fertility. The hypothesis of the present study is that the use of biochar associated with the topsoil technique increases the productivity and yield of cactus, mainly by changing the properties of the soil and its microbiological interactions. To test this hypothesis, we used different sources of biochar (bean husk, coffee grounds and soursop residue) in association with two types of topsoil (Acrisol and Luvisol). Our analyzes revealed changes on plants development, chemical and microbiological soil attributes. The topsoil technique significantly interfered with mean cladode length (COM), stem diameter (DI), plant height (AL), pH, Na+, K+ and urease enzymatic activity, while biochar had a significant effect on microbial respiration rate. In general, our results expand the knowledge about the use of biochar associated with topsoil, suggesting it as a promising, low-cost way that guarantees the conservation and health of the agroecosystem, contributing with important information for the development of alternative technologies to conventional ones.

Low-cost precision agriculture for sustainable farming using paper-based analytical devices.

The United Nations estimates that by 2030, agricultural production must increase by 70% to meet food demand. Precision agriculture (PA) optimizes production through efficient resource use, with soil fertility being crucial for nutrient supply. Traditional nutrient quantification methods are costly and time-consuming. This study introduces a rapid (15 min), user-friendly, paper-based platform for determining four essential macronutrients-nitrate, magnesium, calcium, and ammonium-using colorimetric methods and a smartphone for data reading and storage. The sensor effectively detects typical soil nutrient concentrations, showing strong linearity and adequate detection limits. For nitrate, the RGB method resulted in an R 2 of 0.992, a detection range of 0.5 to 10.0 mmol L-1, and an LOD of 0.299 mmol L-1. Calcium quantification using grayscale displayed an R 2 of 0.993, a detection range of 2.0 to 6.0 mmol L-1, and an LOD of 0.595 mmol L-1. Magnesium was best quantified using the hue color space, with an R 2 of 0.999, a detection range of 1.0 to 6.0 mmol L-1, and an LOD of 0.144 mmol L-1. Similarly, ammonium detection using the hue color space had an R 2 of 0.988, a range of 0.5 to 2.5 mmol L-1, and an LOD of 0.170 mmol L-1. This device enhances soil fertility assessment accessibility, supporting PA implementation and higher food production.

Effects and mechanisms of kitchen waste organic fertilizers application on soil nitrogen transformation, plant pathogenic virulence genes, and metabolites

The application of organic fertilizers enhances soil fertility and alters the function and structure of the soil microbial communities. When subjected to aerobic composting, kitchen waste is transformed into organic fertilizer. However, the ecological benefits and safety risks of kitchen waste organic fertilizers (OF) in soil require further evaluation. Therefore, this study conducted a pot experiment to investigate the effects and mechanisms of OF application on soil properties, crop growth, nitrogen transformation, plant pathogenic virulence genes, and metabolites. The results indicated that OF treatment promoted vitamin C synthesis in pakchoi (35.23–48.00 %) and reduced soil N2O emissions during cultivation compared with inorganic fertilizer (IF) (65.50–68.08 %) (P<0.01). IF treatment significantly increased the abundance of Rhodanobacter (6.41 %) and Nitrobacter (3.16 %), leading to increased N2O emissions (17.94 mg kg−1). Key nitrogen metabolism enzymes and functional genes indicated that nitrification and denitrification pathways were the primary contributors to N2O production. Metagenomic results revealed that IF treatment enhanced virulence gene pathogenicity through quorum sensing (QS), whereas OF treatment reduced virulence gene accumulation in plant pathogenic bacteria. Metabolomic analysis demonstrated that OF treatment significantly upregulated substances beneficial to soil activity and plant growth, while inhibiting pollutant expression. PLS-PM results indicated that soil properties played a pivotal role in shaping the intricate relationships among microbial communities, functional genes, and substance metabolism. This study demonstrated that OF application contributed to the promotion of plant health and optimization of soil ecosystems, thereby providing theoretical support for the further expansion of OF applications in agriculture.

Soil fertility and plant nutrition in an organic olive orchard after 5 years of amendment with compost, biochar or their blend

The agronomic use of compost and biochar as soil amendments may exhibit contrasting results in terms of soil fertility and plant nutrition. The effects of the biennial application of biochar, compost and a blend of compost:biochar (90:10; % dw:dw) on the agronomical performance of an organically managed and well established 25-year-old olive orchard was assessed 5 years after the initial application. The agronomical evaluation was based on the assessment of the soil physical, chemical, and biological characteristics, and the assessment of the soil fertility by both crop production and nutritional status of the orchard, and the bioassay with olive plantlets. Biochar mainly benefited the physical properties (bulk density, total porosity, aeration, water retention capacity) of soil, especially in the top 0–5 cm. Compost and its blend with biochar improved microbial activity, soil nutritional status (increasing the content of soluble organic C, N, and P) and favoured the formation of aggregates in soil. The bioassay conducted with young plantlets confirmed the enhanced soil fertility status in the three amended treatments, particularly in the case of biochar and its blend with compost. However, this effect was not significantly observed in the adult plants after 5 years of application, reflecting the slow response of adult olive trees to changes in fertilization. Based on these results, alongside the desirable long-residence time of biochar in soil and the ready availability of compost, the blend of biochar with compost assayed in this study is defined as a valid strategy for preparing high quality soil organic amendments.

Developed Rhizobium Strains Enhance Soil Fertility and Yield of Legume Crops in Haryana, India.

Three strains of Gram-negative bacterium,Rhizobium, were developed by gamma (γ)-irradiation random mutagenesis. The developed strains were evaluated for their augmented features for symbiotic association, nitrogen fixation, and crop yield of three leguminous plants-chickpea, field-pea, and lentil-in agricultural fields of the northern Indian state of Haryana. Crops treated with developed mutants exhibited significant improvement in plant features and the yield of crops when compared to the control-uninoculated crops and crops grown with indigenous or commercial crop-specific strains of Rhizobium. This improvement was attributed to generated mutants, MbPrRz1 (on chickpea), MbPrRz2 (on lentil), and MbPrRz3 (on field-pea). Additionally, the cocultured symbiotic response of MbPrRz1 and MbPrRz2 mutants was found to be more pronounced on all three crops. The statistical analysis using Pearson's correlation coefficientsrevealed that nodulation and plant biomass were the most related parameters of crop yield. Among the effectiveness of developed mutants, MbPrRz1 yielded the best results for all three tested crops. Moreover, the developed mutants enhanced macro- and micronutrients of the experimental fields when compared with fields harboring the indigenous rhizobial community. These developed mutants were further genetically characterized, predominantly expressing nitrogen fixation marker, nifH, and appeared to belong to Mesorhizobium ciceri (MbPrRz1) and Rhizobium leguminosarum (both MbPrRz2 and MbPrRz3). In summary, this study highlights the potential of developed Rhizobium mutants as effective biofertilizers for sustainable agriculture, showcasing their ability to enhance symbiotic relationships, crop yield, and soil fertility.

The accumulation of fungal not bacterial residue carbon is management-dependent under conventional and organic practices in apple-orchard soil

Organic orchard management has been widely adopted to enhance soil fertility by improving the sequestration of soil organic carbon (SOC). Microbial residue carbon plays an essential role in SOC accumulation; nevertheless, how fungal and bacterial residue carbon (FRC and BRC) changes with different orchard management practices (organic vs. conventional) and the factors influencing their accumulation remain poorly understood. In this study, we quantified the FRC and BRC in the two management practices, compiled this data with the comparisons of plant, soil and microbial properties, and the dominant factor affecting their sequestration was ascertained with a 4-year orchard experiment on the Jiaodong Peninsula. Compared with conventional management, organic management significantly enhanced SOC and the accumulation of FRC and BRC, while it did not alter the contribution of FRC or BRC to SOC. Furthermore, we identified that the primary determinant affecting FRC varied with management type: Plant (AGR, BGG)-soil (SOC, density)-microbe (Nitrospirae) collectively governed FRC in organic soil, whereas soil (pH, density) and microbial (Ascomycota) properties regulated FRC in conventional soil. Nitrospirae abundance and soil pH played pivotal roles in FRC accumulation under organic and conventional management, respectively. Meanwhile, the primary factor influencing BRC was independent of management type: Soil and microbial properties consistently served as the principal determinants of BRC in both management systems, with soil pH and clay being the pivotal factors in organic and conventional managements, respectively. These findings illustrate the divergent regulatory mechanisms of FRC and BRC in organic and conventional management, thereby enhancing our comprehension of microbial-mediated SOC sequestration in organic orchard management.

ZnO nanoparticles in composted sewage sludge enhance soil fertility and rice nutrition but elevate As and Pb accumulation

The widespread use of metal-based nanoparticles (NPs) in a variety of industries results in their release into sewage systems. This presents a risk when composted sewage sludge (CSS) is used as fertilizer. This study examined the effects of ZnO NPs in CSS on rice-soil systems and assessed the health risks associated with consuming rice grown under these circumstances. ZnO NPs were added to CSS at concentrations lower than the regulatory safety limit of 2800 mg Zn kg⁻¹. The results show that higher levels of ZnO NPs in CSS improved the mineral composition of rice grains and increased soil fertility, as evidenced by significant increases in N (1.6–2.3-fold) and K levels. The levels of tyrosine-like fraction, C4, and the biological index (BIX) in soil dissolved organic matter increased upon the introduction of ZnO NPs into CSS, indicating that microbial activity and nutrient cycling have been enhanced. However, the concentrations of As and Pb in rice grains were significantly increased by the elevated levels of ZnO NPs in CSS, reaching up to 1.5 and 2.3 times the control levels, respectively. This increased hazard quotients and pushed hazard indexes beyond acceptable levels, suggesting that rice consumers are at significant health risk. This study underscores the critical need for more stringent and comprehensive regulatory frameworks to ensure the safety of CSS application in crop production and to manage the intricacies of NP use in agriculture.

Algal-based biochar and hydrochar: A holistic and sustainable approach to wastewater treatment

Biochar and hydrochar are carbon-rich solid products of algal and terrestrial biomass obtained through various thermochemical processes, mainly hydrothermal liquefaction, pyrolysis, and hydrothermal carbonization. Both are regarded as economical, potent, and environmentally friendly adsorbents for wastewater remediation. The versatile applicability of biochar and hydrochar, which is due to their enhanced surface physicochemical properties, includes efficient metal biosorption, soil fertility enhancement, and carbon sequestration. Consequently, there has been an increase in research for producing and exploiting biochar and hydrochar from algae. Both micro- and macro-algal biomass have strong potential due to their sustainability footprint and distinct properties. This review focuses on a comprehensive account of the synthesis of algal biochar and hydrochar and use in wastewater treatment to develop innovative solutions for efficient mitigation of several aqueous pollutants and heavy metal ions. The review discusses the various thermochemical production routes, biophysical characterization techniques, and modes of mechanism for wastewater bioremediation. Algal-based biochar and hydrochar are reported to have higher porosity and more diverse functional groups such as amines, hydroxyl, and carboxyl compared to their cellulosic and waste-derived counterparts, demonstrating an increased wastewater remediation efficiency. In addition, presence of inorganic metal including sodium, potassium, magnesium, and phosphorus in algal chars facilitates the formation of mesopores and graphite structures, improving their cation exchange capacity. Moreover, algal chars may exhibit pH buffering capacity, which could help stabilize the pH during wastewater treatment processes. Notably, the low O/C content of algal hydrochars enhances the binding and removal of organic pollutants including toxic dyes and antibiotics. The review highlights the development of modified algal chars to enhance the porosity, surface area, structural integrity, and adsorption capacity enabling a higher bioremediation potential.

Mulching practices alter soil moisture, physico-chemical properties and pineapple (Smooth cayenne) yield

This field experiment was conducted in Chichu Kebele in the Dilla Zuria area from 2020 to 2023. The objective of the experiment was to determine the optimal mulching strategy for enhancing soil fertility and pineapple production by comparing three treatments (grass mulch, plastic mulch, and farmers’ practices without any mulch) using a RCB (Randomized Complete Block) design. The study’s findings showed that the treatments with plastic mulch had the greatest soil moisture content values (18.41%), while the treatments with no mulch had the lowest values (11.39%). Compared to mulched treatments, pineapple planted without mulch had the greatest bulk density values (1.43 g/cm3). Total nitrogen and organic carbon has increase by 34 and 25%, respectively due to plastic mulching. However, total nitrogen and organic carbon has increase by 43 and 37.5%, respectively due to grass mulching. Fruit length was larger by 42.7 and 33.2%, respectively due to plastic and grass mulch compared to the control. However, fruit girth was wider by 54.1 and 43.8%, respectively due to plastic and grass mulches compared to the control. The pineapple with the most fruit yield (71.39 t/ha), fruit length (17.4 cm), fruit girth (46.67 cm), and sucker number (15 pieces) was obtained using plastic mulching. However, pineapple grown without mulch had the lowest yield ever noted. Plastic mulch outperformed farmers’ practices and grass mulching in terms of conserving soil moisture, which increased yield and yield characteristics. For the baseline, the marginal rate of return generated by the plastic and grass mulch treatments was 118.5 and 93.65%, respectively. Thus, the study’s best recommendation for improving soils and achieving a high pineapple fruit yield is to grow pineapples using plastic mulch.

Unveiling the Impact of Soil Prebiotics on Rhizospheric Microbial Functionality in Zea mays L.

Prebiotics, a subset of biostimulants, have garnered attention for their potential to enhance soil conditions and promote plant growth, offering a promising alternative to conventional agricultural inputs. This study explores how two commercial prebiotics, K1® and NUTRIGEO L® (SPK and SPN), impact soil functions compared to a control (SP). The experiment involved agricultural soil amended with organic wheat straws and cultivated with Zea mays L. Previous research demonstrated substantial effects of these prebiotics on plant biomass, soil parameters, and microbial community ten weeks after application. The present study delves deeper, focusing on soil microbial abundance, enzyme activities, and metabolic diversity. Analysis revealed that SPN notably increased the fungi-to-bacteria ratio, and both prebiotics elevated the activity of several key enzymes. SPN enhanced α-glucosidase and β-galactosidase activities, while SPK increased arylsulfatase, phosphatase, alkaline phosphatase, and urease activities. Enzymatic indexes confirmed the positive impact on soil functional diversity and fertility. Additionally, prebiotic treatments showed distinct metabolic profiles, with SPK degrading eleven carbon sources more rapidly across five groups and SPN accelerating the decomposition rate of four carbon sources from three groups. These findings highlight the ability of prebiotics to shape microbial communities and enhance soil fertility by modulating their functional activity and diversity.

Enhancing agricultural output: Investigating the impact of advanced organic formulations on crop productivity, nutrient use efficiency, and profitability in a multi-crop system

The significance of integrating agricultural by-products such as paddy husk ash (PHA) and potato peels with organic fertilizers lies in enhancing soil fertility, increasing crop yields, and reducing reliance on traditional organic fertilizers like farmyard manure (FYM) or compost alone. Grounded in sustainable agriculture and nutrient management frameworks, this study examines the impact of diverse formulations derived from agricultural waste on productivity, nutrient efficiency, and profitability in a pigeon pea–vegetable mustard–okra cropping system. A two-year field experiment (2020–2022) at ICAR-IARI, New Delhi tested seven nutrient sources viz., (T1) control, (T2) 100% RDN through FYM, (T3) 100% RDN through improved RRC, (T4) 100% RDN through PHA based formulation, (T5) 75% RDN through PHA based formulation, (T6) 100% RDN through PPC based formulation and (T7) 75% RDN through PPC based formulation that were tested in RBD and replicated thrice. Treatment T4 had significant effect on seed yield of pigeon pea (1.89 ± 0.09 and 1.97 ± 0.12 t ha−1), leaf yield of vegetable mustard (81.57 ± 4.59 and 82.97 ± 4.17 t ha−1), and fruit yield of okra (13.54 ± 0.82 and 13.78 ± 0.81 t ha−1) grown in rotation, followed by treatment T6 and T2 during both the years respectively over control. Enhanced system uptake of N, P and K along with system gross and net returns in T4, showed increases of 78.9%, 83.8%, 72.4%, 54.4% and 56.8% in the first year and 77.5%, 80.8%, 77.7%, 54.8% and 57.4% in the second year, respectively, over control. Treatment T4 significantly improved apparent recovery by 66.3% and 69.2% in pigeon pea, 64.7% and 47.9% in vegetable mustard, and 72.7% and 79.4% in okra over T3, averaged across two years. Based on the above findings, (T4) 100% RDN through PHA-based formulation, and (T6) 100% RDN through PPC-based formulation can be recommended for areas with a shortage of FYM but availability of rice husk ash/potato peels for sustainable agricultural wastes and improved sustainability.

Synergistic enhancement of cadmium immobilization and soil fertility through biochar and artificial humic acid-assisted microbial-induced calcium carbonate precipitation

Microbially induced carbonate precipitation (MICP) is emerging as a favorable alternative to traditional soil remediation techniques for heavy metals, primarily due to its environmental friendliness. However, a significant challenge in using MICP for farmland is not only to immobilize heavy metals but also to concurrently enhance soil fertility. This study explores the innovative combination of artificial humic acid (A-HA), biochar (BC), and Sporosarcina pasteurii (S. pasteurii) to mitigate the bioavailability of cadmium (Cd) in contaminated agricultural soils through MICP. X-ray diffraction (XRD) and scanning electron microscope (SEM) analyses revealed that the integration of BC and A-HA significantly enhances Cd immobilization efficiency by co-precipitating with CaCO3. Moreover, this treatment also improved soil fertility and ecological functions, as evidenced by increases in total nitrogen (TN, 9.0–78.2 %), alkaline hydrolysis nitrogen (AN, 259.7–635.5 %), soil organic matter (SOM, 18.1–27.9 %), total organic carbon (TOC, 43.8–48.8 %), dissolved organic carbon (DOC, 36.0–88.4 %) and available potassium (AK, 176.2–193.3 %). Additionally, the relative abundance of dominant phyla such as Proteobacteria and Firmicutes significantly increased with the introduction of BC and A-HA in MICP. Consequently, the integration of BC and A-HA with MICP offers a promising solution for remediating Cd-contaminated agricultural soil and synergistically enhancing soil fertility.

Salt-tolerant plant growth-promoting bacteria as a versatiletool for combating salt stress in crop plants.

Soil salinization poses a great threat to global agricultural ecosystems, and finding ways to improve the soils affected by salt and maintain soil health and sustainable productivity has become a major challenge. Various physical, chemical and biological approaches are being evaluated to address this escalating environmental issue. Among them, fully utilizing salt-tolerant plant growth-promoting bacteria (PGPB) has been labeled as a potential strategy to alleviate salt stress, since they can not only adapt well to saline soil environments but also enhance soil fertility and plant development under saline conditions. In the last few years, an increasing number of salt-tolerant PGPB have been excavated from specific ecological niches, and various mechanisms mediated by such bacterial strains, including but not limited to siderophore production, nitrogen fixation, enhanced nutrient availability, and phytohormone modulation, have been intensively studied to develop microbial inoculants in agriculture. This review outlines the positive impacts and growth-promoting mechanisms of a variety of salt-tolerant PGPB and opens up new avenues to commercialize cultivable microbes and reduce the detrimental impacts of salt stress on plant growth. Furthermore, considering the practical limitations of salt-tolerant PGPB in the implementation and potential integration of advanced biological techniques in salt-tolerant PGPB to enhance their effectiveness in promoting sustainable agriculture under salt stress are also accentuated.

Exploring the impact of mycogenic selenium nanoparticles on production of exopolysaccharides from arid zone bacteria

Modulating bacterial exopolysaccharides (EPS) with nanoparticles is an emerging application of nanotechnology due to the enhancement of soil fertility, encouragement of nutrient uptake, and plant growth in agriculture. This study highlights the seamless integration of nanotechnology with EPS, the fungus, Serendipita indica strain is used here to reduce selenium ions and forms selenium nanoparticles (Se NPs). Se NPs has been characterized by visual observation, UV–vis spectroscopy, FTIR, TEM, SEM-EDX, XRD, DLS and Zeta potential. Production of EPS was monitored in the presence of Se NPs. Extracted EPS was characterized by FTIR, SEM-EDX, HPLC, and NMR. Results exhibit the successful formation of spherical, crystalline Se NPs with size ranging between 20-80 nm with 92.24% selenium. Response surface methodology (RSM) was used to identify and optimise the production of exopolysaccharides (EPS) from Bacillus subtilis that was isolated from arid zone agricultural soil. The central composite rotatable design (CCRD) exhibited the highest yield of EPS 11.332 g/l. EPS was then characterized by FTIR, HPLC, NMR, and SEM which revealed the presence of carboxyl and hydroxyl groups and flakes-like structure of EPS. Hence, the present work will pave the way for the application of nanotechnology for increasing EPS production and will also offer new dimensions for further research.

Effects of the combined compost of grape branches and sheep manure on a soil-microorganism-chardonnay (Vitis vinifera L.) plant ecosystem

A low-cost and sustainable composting strategy of grape branches and sheep manure is needed for vineyards. This study investigated the response of soil and grape plant characteristics to the compost, detected the changes in soil microbial community by high-throughput sequencing, and analyzed the relationship between soil microorganisms and soil characteristics and grape plant characteristics. The BM55 (1:1 grapevine branch to sheep manure by volume) group was the most effective treatment for increasing soil nutrients and enzyme activities. The BM3711Abbreviations: CK, Control check; GB, 100 % Grape branches; BM73, 70 % grape branches and 30 % sheep manure; BM55, 50 % grape branches and 50 % sheep manure; BM37, 30 % grape branches and 70 % sheep manure; SM, 100 % Sheep manure; Bd, Bulk density; Fc, Field capacity; EC, Electric conductivity; OM, Organic carbon; TC, Total C; TN, Total N; NO3, NO3--N; NH4, NH4+-N; OP, Olsen-P; AK, Available K, S-AKP/ALP, Soil alkaline phosphatase; S-CAT, Soil catalase; S-UE, Soil urease; S-SC, Soil sucrase. SS, Soluble solids; TA, Titratable acid; Ci, Intercellular CO2 concentration; Tr, Transpiration rate; Gs, Stomatal conductance; Pn, Net photosynthetic rate; SPAD, Chlorophyll content. (3:7 vol ratio of grapevine branches to sheep manure) treatment was the most effective in increasing fruit yield and quality. The dominant species of bacteria (Proteobacteria, Actinobacteria, Bacteroidetes, Ascomycota, and Basidiomycota) did not change but their relative abundance changed. Redundancy analysis showed that the soil biotic factors, abiotic factors, and microorganisms interact to form a complex relationship, in which biotic factors were the key factors influencing the composition and abundance of microbial communities, and the bacterial community was more sensitive than the fungal community. The combined composting stimulated microorganisms to participate in the synthesis and circulation of soil nutrients, which was not achieved by returning to the field respectively. Therefore, the combined composting is an effective way to enhance soil fertility, promote microbial metabolism, and improve fruit quality in vineyards, promote microbial metabolism, and improve fruit quality. Our results also provide a valuable scientific basis for understanding the interaction between soil microorganisms and soil properties as well as grape plant characteristics.

Role of Bacteria in Plant Nutrient Mobilization: A Review

Plant roots are the site of dynamic and complex interactions between a variety of microorganisms, such as fungi, bacteria, and archaea. Plant Growth-Promoting Rhizobacteria (PGPR) is one of those that are important for improving the health and growth of plants. Bacteria are among the most abundant and diverse microorganisms in the rhizosphere. These bacteria contribute to various processes, including nitrogen fixation, phosphate solubilization, and production of plant growth-promoting substances, thereby enhancing plant nutrient uptake and growth. Fungi are another important component of the rhizosphere microbiota. These microbes are used as bioinoculants in the agricultural field, replacing the traditional use of pesticides. Bioinoculants do not show any detrimental impact on the soil's plant and animal life as they are eco-friendly, highly efficient, and can be utilized as bio-pesticides that do not have any harmful influence on plant products. Understanding the composition and functions of rhizosphere microbiota is crucial for developing sustainable agricultural practices that harness the beneficial interactions between plants and microorganisms to enhance soil fertility and crop productivity while minimizing environmental impacts. This review examines the emerging use of microorganisms in the agricultural field, which can replace the chemical fertilizers that are proven hazardous if used extensively over crops, specifically regarding the important micronutrients required by the plant. The current study addresses the gap in the effectiveness of these microorganisms as bio-inoculants in the rhizosphere and future aspects of the microbes for crop productivity.

Effect of vermicompost additive on physical, chemical and dielectric properties of soil and its modeling

The present study focuses on the effects of vermicomposting on various soil properties, particularly emphasizing the dielectric characteristics of soil. Vermicomposting is known to significantly enhance soil fertility and improve its physical aspects such as aeration, porosity and water retention. In this analysis, a modified probe arrangement has been employed to determine how varying levels of vermicompost influence the soil’s dielectric properties within the radio and microwave spectrum (10 MHz-14 GHz). A modified Dak-12 open-ended coaxial probe, paired with a vector network analyzer, was utilized for this purpose to overcome the drawbacks of standard arrangement. The results show that vermicompost strongly affects the soil’s physical attributes (pH, bulk density, porosity) and also its chemical properties, along with its dielectric behavior. The study further explored the role of different factors such as the concentration of vermicompost, frequency and temperature on soil’s dielectric response. To accurately and swiftly gauge these effects, Response Surface Methodology (RSM) has been employed to predict the dielectric properties (ε’ and ε’’) of the soil. The high precision of these models, with R 2 values of 0.9729 for ε’ and 0.9487 for ε’’, underscores their effectiveness in evaluating the impact of vermicompost on various soil properties.