Green iron oxide nanoparticles and magnetic nanobiochar: enhancing tomato performance, phytochemicals, and root-knot nematode resistance.

BACKGROUND: Green nanoparticles are considered to be an effective strategy for improving phytochemicals and raising productivity in soil infected by root-knot nematodes. This work aims to understand the characteristics of certain nanomaterials, including non-iron (nFe), green non-iron (GnFe), and green magnetic nanobiochar (GMnB), and the effect of adding them at 3 and 6 mg kg- 1 on phytochemicals and tomato (Solanum lycopersicum) plant growth in soils infected by root-knot nematodes. RESULTS: Spectroscopic characterization of nanomaterials showed that nFe, GnFe, and GMnB contained functional groups (e.g., Fe-O, S-H, C-H, OH, and C = C) and possessed a large surface area. Application of GMB at 6 mg kg- 1 was the most efficient treatment for increasing the phytochemicals of the tomato plant, with a rise of 123.2% in total phenolic, 194.7% in total flavonoids, 89.7% in total carbohydrate, 185.2% in total free amino acids, and 165.1% in total tannin compared to the untreated soil. Tomato plant growth and attributes increased with increasing levels of soil nano-amendment in this investigation. The addition of GnFe3 and GnFe6 increased the reduction of root galls of root-knot nematodes by 22.44% and 17.76% compared with nFe3 and nFe6, respectively. The inclusion of the examined soil nano-amendments increased phytochemicals and reduced the total number of root-knot nematodes on tomato plants at varying rates, which played a significant role in enhancing tomato growth. CONCLUSIONS: In conclusion, treating tomato plants with GnFe or GMnB can be used as a promising green nanomaterial to eliminate root-knot nematodes and increase tomato yield in sandy clay loam soil.

Effect of integration of poultry manure and vinasse on the abundance and diversity of soil fauna, soil fertility index, and barley (Hordeum aestivum L.) growth in calcareous soils.

BACKGROUND: In Egypt, calcareous soils represent a large part of desert soils suffering from a shortage of nutrients and organic matter, affecting production and biological diversity in agroecosystems. Organic wastes, negatively affect the environment, recycling it as a promising technology in different farming systems, and its impact on crop productivity and soil fauna is largely unknown. In this study, the effects of integrating poultry manure (PM) alone or combined with vinasse (V) at rates of 4.2 g kg- 1 and 6.3 g kg- 1 in pots, on improving soil fauna diversity, soil fertility, soil consistency and yield of barley (Hordeum aestivum L.) grown in a calcareous soil were investigated. RESULTS: The results showed that the addition of PM alone or combined with V at different rates led to a significant increase in the microbial biomass carbon (MBC), organic matter (OM), NPK soil availability and yield of barley. The addition of 6.3 g PM and 4.2 g V kg- 1 soil have the best results in OM with 65.0% compared to control, and V contributes more than 16% of them. Prostigmata and Collembola were the dominant groups and accounted for 43.3% and 50.0% in the PM1 and 50.0% and 20.0% in the PM2 of the total individuals, respectively. Shannon and Evenness indices increased significantly with the soil amended by PM alone or combined with V. Soil fauna plays a key role in soil consistency because of a significant relationship between soil fauna and soil OM, MBC and soil fertility index. The addition of 6.3 g PM and 4.2 g V kg- 1 soil gave the best results in grain yield by 76.90% compared to the control. CONCLUSION: In conclusion, the interaction between PM and V can be used as a promising organic amendments to increase barley yield and improve efficiency of a recycled PM and V on soil fauna and soil fertility of calcareous soil.

Spectroscopic studies on the phosphorus adsorption in salt-affected soils with or without nano-biochar additions.

Biochar amendment may be an effective solution of maintaining phosphorus (P) and sustaining agricultural production in salt affected soils. However, the behavior of P adsorption in salt-affected soils with nano-biochar (nB) amendment is unclear. Batch adsorption experiments were conducted to investigate the impacts of different levels of soil salinity amended with nB at rates of 0, 0.10%, 0.20%, and 0.50% (w/w) on the P adsorption isotherm and also, mechanisms of P adsorption by using spectroscopic analysis. The results showed that P adsorption increased with increasing soil salinity with or without nB addition. Under level of 120 mg P L-1, adsorption capacity of P increased from 992.8 mg kg-1 for high saline soil (S5) to 1144.0 mg kg-1 after treated with 0.20% nB. The results of P adsorption were agreed with Langmuir and Freundlich isotherm models. Fourier transform infrared analysis (FTIR) of nB showed that the surface of nB decorated with oxygenated functional groups which play an important role in the adsorption of P anions. Analyzes of FTIR and XRD indicated that the main adsorption mechanism for P adsorption on nB in salt affected soils was surface precipitation. Our findings suggest that the nano-biochar amendment in salt affected soils can be a promising enhancer for P adsorption.

Biosynthesis of iron oxide nanoparticles using plant extracts and evaluation of their antibacterial activity.

The biosynthesis of iron oxide nanoparticles has received increasing attention in the field of food nanotechnology because of their non-toxicity, high efficiency, high antibacterial power, and decontamination features. Therefore, biosynthesis of iron oxide nanoparticles (nFe) was prepared from the leaves of some vegetables, such as cabbage (C) and turnips (T), as well as moringa leaves (M). Alcoholic extracts of these nanoparticles were also tested on Staphylococcus aureus and Escherichia coli to evaluate their antibacterial activity. The results revealed that the particle sizes of the biosynthesis nanomaterials studied ranged from 12.99 to 22.72 nm, and the particles were spherical, irregular, and surrounded by black color. It also contains many functional groups and minerals. Iron nanoparticles modified with Moringa oleifera extract at a concentration of 200 ppm had the highest phenol content compared to other biosynthesis nanoparticles studied. TnFe and MnFe at 200 ppm had a maximum zone of inhibition of 25 mm and 24 mm against Staphylococcus aureus and Escherichia coli, respectively. While the minimum inhibition zone of 8.0 mm was observed at 25 ppm for nFe against Escherichia coli. Therefore, it is recommended to use these extracts of biosynthesis iron oxide nanoparticles as antibacterial agents for stored foods.

Effect of Nano-Zinc Oxide, Rice Straw Compost, and Gypsum on Wheat (Triticum aestivum L.) Yield and Soil Quality in Saline-Sodic Soil.

The salinity and alkalinity of soils are two fundamental factors that limit plant growth and productivity. For that reason, a field study conducted at Sakha Agric. Res. Station in Egypt during the 2022-2023 winter season aimed to assess the impact of gypsum (G), compost (C), and zinc foliar application in two images, traditional (Z1 as ZnSO4) and nanoform (Z2 as N-ZnO), on alleviating the saline-sodic conditions of the soil and its impact on wheat productivity. The results showed that the combination of gypsum, compost, and N-ZnO foliar spray (G + C + Z2) decreased the soil electrical conductivity (EC), sodium adsorption ratio (SAR), and exchangeable sodium percentage (ESP) by 14.81%, 40.60%, and 35.10%, respectively. Additionally, compared to the control, the G + C + Z2 treatment showed improved nutrient content and uptake as well as superior wheat biomass parameters, such as the highest grain yield (7.07 Mg ha-1), plant height (98.0 cm), 1000-grain weight (57.03 g), and straw yield (9.93 Mg ha-1). Interestingly, foliar application of N-ZnO was more effective than ZnSO4 in promoting wheat productivity. Principal component analysis highlighted a negative correlation between increased grain yield and the soil EC and SAR, whereas the soil organic matter (OM), infiltration rate (IR), and plant nutrient content were found to be positively correlated. Furthermore, employing the k-nearest neighbors technique, it was predicted that the wheat grain yield would rise to 7.25 t ha-1 under certain soil parameters, such as EC (5.54 dS m-1), ESP (10.02%), OM (1.41%), bulk density (1.30 g cm-3), infiltration rate (1.15 cm h-1), and SAR (7.80%). These results demonstrate how adding compost and gypsum to foliar N-ZnO can improve the soil quality, increase the wheat yield, and improve the nutrient uptake, all of which can support sustainable agriculture.

Effect of selenium form and dose on camelthorn (Alhagi maurorum Medik) grown on a metal-contaminated soil.

Selenium (Se) enhances the resistance of plants exposed to metal stress and can be used to lessen the impacts of toxic elements and to enhance the effectiveness of the plants used to clean up polluted sites. There is no information available about the optimum dose and form of Se to stimulate the camelthorn (Alhagi maurorum Medik) plant, which is one of the plants used in the phytostabilization of toxic elements. The impacts of selenate (Se-VI) and selenite (Se-IV) on the phytoremediation of toxic metals from loamy soils by camelthorn were investigated in a pot experiment. Se-VI and Se-IV were added to the soil at doses of 0, 5, and 10 mg Se kg-1 soil, and each treatment was repeated five times. Se-VI and Se-IV, significantly increased plant growth and nutrient uptake. The addition of Se, either from Se-VI or Se-IV, significantly increased the superoxide dismutase (SOD) and peroxidase (POD) enzymes, and the non-enzymatic antioxidant compounds, i.e., proline and phenols, compared to the control. The addition of Se strengthened the defense against metal stress, and Se-VI outperformed Se-IV in boosting camelthorn's resistance to hazardous metal contamination. Selenium increased the accumulation of metal in the root of camelthorn and reduced root-shoot transfer. The best technique to boost camelthorn plants' capacity to clean up metal-contaminated soils is to supplement them with selenium in the form of selenate at a concentration of 10 mg Se kg-1 soil.

Nano-Bioremediation of Arsenic and Its Effect on the Biological Activity and Growth of Maize Plants Grown in Highly Arsenic-Contaminated Soil.

Arsenic (As)-contaminated soil reduces soil quality and leads to soil degradation, and traditional remediation strategies are expensive or typically produce hazardous by-products that have negative impacts on ecosystems. Therefore, this investigation attempts to assess the impact of As-tolerant bacterial isolates via a bacterial Rhizobim nepotum strain (B1), a bacterial Glutamicibacter halophytocola strain (B2), and MgO-NPs (N) and their combinations on the arsenic content, biological activity, and growth characteristics of maize plants cultivated in highly As-contaminated soil (300 mg As Kg-1). The results indicated that the spectroscopic characterization of MgO-NPs contained functional groups (e.g., Mg-O, OH, and Si-O-Si) and possessed a large surface area. Under As stress, its addition boosted the growth of plants, biomass, and chlorophyll levels while decreasing As uptake. Co-inoculation of R. nepotum and G. halophytocola had the highest significant values for chlorophyll content, soil organic matter (SOM), microbial biomass (MBC), dehydrogenase activity (DHA), and total number of bacteria compared to other treatments, which played an essential role in increasing maize growth. The addition of R. nepotum and G. halophytocola alone or in combination with MgO-NPs significantly decreased As uptake and increased the biological activity and growth characteristics of maize plants cultivated in highly arsenic-contaminated soil. Considering the results of this investigation, the combination of G. halophytocola with MgO-NPs can be used as a nanobioremediation strategy for remediating severely arsenic-contaminated soil and also improving the biological activity and growth parameters of maize plants.

Enhancing Maize Yield and Soil Health through the Residual Impact of Nanomaterials in Contaminated Soils to Sustain Food.

Studying the impact of residual soil nanomaterials is a promising challenge for sustainable agricultural development to improve soil health and crop productivity. The objective of this study is to assess the long-term impacts of 50, 100, and 250 mg kg-1 soil of nanobiochar (nB) and nano-water treatment residues (nWTR) on the fertility, biological activity, and yield of maize (Zea mays L.) growing in heavy metal-contaminated soils. The results showed that when nB and nWTR were added in larger quantities, the concentrations of lead (Pb), nickel (Ni), cadmium (Cd), and cobalt (Co) extracted with DTPA decreased. With the addition of nB or nWTR, it also showed a significant increase in exchangeable cations, cation exchange capacity (CEC), soil fertility, soil organic matter (OM), microbial biomass carbon (MBC), and a decrease in soil salinity and sodicity. Catalase and dehydrogenase activities rose as nB addition increased, while they decreased when nWTR addition increased. In comparison to the control, the addition of nB and nWTR greatly boosted maize yield by 54.5-61.4% and 61.9-71.4%, respectively. These findings suggest that the researched nanomaterials' residual effect provides an eco-friendly farming method to enhance the qualities of damaged soils and boost maize production. Our research suggested that adding recycling waste in the form of nanoparticles could immobilize heavy metals, improve soil characteristics, and increase the soil's capacity for productivity.

Phosphogypsum and poultry manure enhance diversity of soil fauna, soil fertility, and barley (Hordeum aestivum L.) grown in calcareous soils.

Enrichment of calcareous soils with phosphogypsum and poultry manure amendments could increase nutrient availability, improve calcareous chemical characteristics, and enhance barley plant growth. In the current study, phosphogypsum (PG) and poultry manure (PM) were used to determine the effects of PG and PM application on soil fauna diversity, soil fertility, and barley yield. The pot experiment treatments were: C: control; PG1: 4.20 g kg-1 soil; PG2: 6.30 g kg-1 soil; PM1: 4.20 g kg-1 soil; PM: 6.30 g kg-1 soil, and their combinations. The results indicated that the application of PM alone or combined with PG had significant effects on the microbial biomass carbon (MBC), organic matter (OM), soil NPK availability, and yield of barley. Collembola and Prostigmata accounted for 50.0 and 43.3%, respectively, of the total number of soil fauna. Shannon and evenness indices increased significantly in the soil amended with PM alone or combined with PG. Amended soil with PG and/or PM significantly increased the yield and yield components of plants compared to the control. The PM1PG2 treatment increased the yield by 76.2% above the control.

Safe and economic disposal of water treatment residuals by reusing it as a substitution layer in roads construction (spectroscopic and geotechnical study).

Cost-effective construction techniques, such as reusing waste materials, play important role in dramatically reduce costs. In recent years, sludges have gained considerable attention as a geotechnical material. Increase in the demand of drinking water from purification plants produces a huge amount of water treatment residuals (WTRs). The disposal of such residues can be considered problematic issue. In this study, innovate and economic method to disposal of WTRs was presented. Comprehensive experimental investigations have been done to determine the effect of utilizing WTRs as a substitution layer in collapsing soil through roads construction processes. The investigations extended to the geotechnical and spectroscopic properties. Tests were carried out on the soil sample mixing with 0, 4, 8, 12, and 16% of WTRs. The samples morphology and composition are characterized by scanning electron microscopy (SEM) and the energy dispersive spectroscope analyzer (EDS). The microstructure and organic constituents are analyzed by X-ray diffraction (XRD) and the Fourier transform infrared (FTIR). The geotechnical measurements include particle size distribution (PSD), single odometer test (SOT), modified proctor test, and the California bearing ratio (CBR). The microstructure analysis confirms that WTRs acted as a pore filler to decrease in porosity and create a denser and solidified structure which reduces the suction and maximum collapse potential. Mineralogical analyses implied that the soil with WTRs turns into a rich medium with metal cations and organic matters that react with minerals to form binding materials. From the geotechnical point of view, WTRs can be safely deposed by mixing with collapsing soil as a subgrade of road construction up to a value of 10% without any impact or reduction on CBR values. The reduction in the required amount of subgrade required by 10% effectively decreases the cost of road construction. Moreover, the results illustrate the remarkable improvement in the collapse potential of the soil, which is reduced by about 24.7% by mixing it with 10% WTRs.