Soil Fertilization Research Articles

Inoculation of Arthrobacter sp. improves the growth of Acanthocalycium sp. and the fruits nutraceutical quality and the flowers longevity

Research objective: The aim of this work is on the inoculation in the growing medium of Arthrobacter sp. and its effects on the growth, flower quality and longevity of cactus plants. To this end, the study of biometric parameters, i.e. plants and flowers (height, weight, number and duration), as well as root growth (weight), and the presence of disease were quantified as measures of plant productivity and compared with those obtained from non-inoculated plants. The use of alginate microspheres as a means of bacterial inoculation was also considered. Materials and Methods: Seedlings of Acanthocalycium (2 years old) Ferrarii, A. Glaucum and A. Violaceum were immediately planted in pots after purchase, in substrate containing (sand 20%, pumice 20% and peat 60%; pH 7; electrical conductivity 0.7 dS/m; total porosity 80% (v/v). A randomised complete block design was applied for the experiments: the pots were randomly divided into two series, one series was inoculated with the bacteria and the other non-inoculated was used as a control. Each month, plant growth was assessed according to (1) plant height, (2) vegetative and root weight, (3) number of flowers per plant (4) flower duration. In addition, the occurrence of possible diseases, in particular Fusarium sp. and Verticillium sp., was assessed. Total flavonoids, total phenols and antioxidant activity were also analysed. Results and Discussion: The experiment showed that the use of Arthrobacter sp. can indeed significantly improve the vegetative and root growth of Acanthocalycium sp. cacti. In addition, there was a significant improvement in the number and floral longevity as well as in the phenol, flavonoid and antioxidant content of the fruits of the inoculated plants compared to the untreated control. The experiment also showed that mortality due to the pathogens Fusarium sp. and Verticillium sp. was significantly reduced in the treated plant. In agreement with these authors, we found that PGPB treatments increased agronomic parameters and improved Fusarium and Verticillium resistance. In general, the application of biostimulants can increase the synthesis of bioactive compounds in plants by increasing resistance to phytopathologies. Inoculation with Arthrobacter sp. led to a significant reduction in the number of dead plants with respect to the diseases analysed. As a result of the stimulating action demonstrated in Acanthocalycium, bioproducts suitable for nutraceutical purposes may be developed in the future. Therefore, new microbe-assisted technologies can help plants to resist stress conditions, improving their tolerance and productivity. Conclusions: Due to its ‘multifunctionality’, the genus Acanthocalycium is considered as one of the species of the future, for ornamental use and medicinal aspects, and new results may help reveal its potential in the context of the bio-economy and circular economy. As natural resources and cultural practices are crucial in defining the quality of flowers when destined for food/nutraceutical applications, the inoculation of Acanthocalycium with Arthrobacter sp. can be envisaged to provide better plant growth under conditions of environmental stress, or as a soil fertiliser, but also to improve the synthesis of natural products used for therapeutic applications.

Effect of layered fertilizer strategies on rapeseed (Brassica napus L.) productivity and soil macropore characteristics under mechanical direct-sowing

Layered fertilization parameters affects crop root system configuration and growth distribution, which in turn affects soil pore properties and aggregate structure. Therefore, understanding the spatial distribution of the root system and soil pore space is helpful in choosing a reasonable fertilization ratio in production practice, which ensures high and stable crop yields and at the same time improves fertilizer utilization and soil health. Albeit the impact of layered fertilization ratio at varied rates on soil pore characteristics in the soil profile at a microscale level remains limited. This study quantifies the impacts of layered fertilization ratio under on rapeseed root distribution and soil pore characteristics using the root analysis system and X-ray computed tomography (XCT). A new fertilization pattern that shallow-deep layer synchronized mechanical sowing was using, rotary tillage mixed fertilization in the shallow layer and 10 cm side-deep band fertilization in the deeper layer. It set five ratios of fertilizer amounts between shallow and deep layers as 0:4 (FD), 1:3 (FL), 2:2 (FM), 3:1 (FH), and 4:0 (F0), with non-fertilization (CK) as the control treatment. The results indicated that layered fertilization effectively improved the rape root conformation and spatial distribution, significantly increased total soil porosity and moisture content, and reduced soil bulk density and resistance (P < 0.05). Additionally, root configuration is closely related to soil pore structure and crop yield. Notably, compared with other treatments, the macroscopic porosity, equivalent pore diameter, hydraulic radius and roundness of FM treatment are significantly improved, and it effectively improves the yield and quality of rapeseed. Correlation analysis showed that the root system configuration parameters were negatively correlated with soil bulk density and resistance but positively correlated with soil moisture content, and macropore morphology parameters and rapeseed yield. Our study demonstrate that layered fertilization can improved rape growth and soil macropore porosity, but its effect depends on good tillage macropore characteristics and distribution created by reasonable fertilization ratio, which provided a theoretical basis for high-yield, efficient, green, and sustainable mechanized direct-sowing production of rapeseed.

The immediate causes of the Amhara Fano Force's rebellion against the government of Abiy Ahmed

ABSTRACT With careful investigation, this article looks into the immediate causes that led to Amhara Fano's conflict with Abiy Ahmed's administration. Even though the people of Amhara stayed silent through many pains, 2022 was the turning point for Amhara Fano to start official conflict with Abiy Ahmed’s administration. The research design for the study is an exploratory case study. Document review, audio-visual sources, and a semi-structured interview were employed to investigate the recent reasons for Amhara Fano Force's conflict with Abiy Ahmed’s administration. The Pretoria agreement, the establishment of Sheger City, the attempt to tear down the Amhara Regional Force, the absence of trust with Abiy Ahmed's leadership, and delay in providing soil fertiliser to Amhara farmers were a few recent factors that led to the Amhara Fano Force struggle. Based on these findings, the researcher suggests that before the political apparatus, economy, and humanitarian security of Ethiopia are at risk again and affect East Africa, international organisations and international communities need to be part of the solution and provide assistance in establishing negotiation and agreement between these two warring factions like they did for the Tigray People’s Liberation Front (TPLF) and the federal government of Ethiopia.

Rice Response to Struvite and Other Phosphorus Fertilizers in a Phosphorus-Deficient Soil Under Simulated Furrow-irrigation

AbstractWastewater-recovered phosphorus (P), in the form of the mineral struvite (MgNH4PO4⋅6H2O), may provide a sustainable alternative to decreasing rock-phosphate reserves. Struvite can be generated via precipitation methods, potentially reducing the amount of P runoff to aquatic ecosystems. The objective of this greenhouse tub study was to evaluate the effects of chemically- and electrochemically precipitated struvite (CPST and ECST, respectively) on above- and belowground plant response in a hybrid rice (Oryza sativa) cultivar grown using furrow-irrigation compared to other common fertilizer-P sources [i.e., triple super phosphate (TSP) and diammonium phosphate (DAP)]. Rice was grown in tubs in controlled environmental conditions in a greenhouse for a full growing season in a P-deficient, silt-loam soil (Typic Glossaqualfs). Plant nutrients (i.e., N. P. K. Mg, Zn) were determined at the end of the growing season through Mehlich-3 extraction. Below- and aboveground rice dry matter (DM), root-P concentration and uptake, aboveground tissue-P uptake, total aboveground and total plant DM, grain yield, and grain P uptake from CPST and ECST did not differ from DAP or TSP. However, aboveground tissue-P concentration was greater (P &lt; 0.05) from TSP (0.05%) than from ECST, CPST, and the unamended control (UC). Total aboveground (i.e., vegetative plus grain) tissue-P uptake was largest (P &lt; 0.05) from TSP (4.8 g m− 2), which did not differ from DAP or CPST, and was at least 1.1 times greater than from ECST and the UC. Despite only a few differences from the UC, the many similar rice responses among struvite and other common fertilizer-P sources suggest that struvite, especially ECST, is a potential alternative fertilizer-P source that warrants further research into struvite’s role in food production.

Cocoa Farmers’ Perceptions of Drought and Adaptive Strategies in the Ghana–Togo Transboundary Cocoa Belt

This study investigated the perception of drought by cocoa farmers and explored the effectiveness of adaptive strategies (ASs) used in smallholding farms in the transboundary region between Ghana and Togo. Drought significantly threatens cocoa production in this region, affecting farmers’ livelihoods and cocoa supply chains. This study used a multistage sampling approach, which involved surveys with questionnaires administered to 330 cocoa farmers throughout the study area, along with on-site observations. Statistical analysis included binary logistic and Poisson regression models to explore the relationship between farmer socioeconomic characteristics and adaptation practices. The findings revealed that cocoa farmers in the region have a nuanced understanding of drought, attributed to changing climatic patterns and unsustainable land management practices such as deforestation. To mitigate its impacts, farmers employ a variety of ASs, including investment in farm management, soil management, and intercropping with crop diversification. Furthermore, socioeconomic factors, including age, formal education, household size, land tenure right, adaptation cost assessment, and an underestimation of self-efficacy, were shown to affect the choice in the AS. Among the ASs adopted, only farm management practices (weeding, pruning, fertilizer application, etc.) significantly improved yield. This study contributes to understanding drought as a critical issue for cocoa farmers and the adaptation practices used by smallholder cocoa farmers. Given that among the strategies adopted, only farm management practices, also known as good agricultural practices (GAPs), significantly improves yield, this study recommends well-designed and innovative packages of sustainable farm management based on farm and owner characteristics. These include irrigation schemes, timely soil fertilizer monitoring and supply, and the provision of drought-resistant varieties along with technical itineraries. Additional interventions require drought emergency responses, with other factors such as education and financial support mechanisms expected to improve farmers’ timely decision-making to adapt and improve cocoa production resilience to drought episodes in international transboundary regions with complex governance structures.

Effects of Microplastics, Fertilization and Pesticides on Alien and Native Plants

Plastic mulches, fertilizers and pesticides have been extensively employed in agriculture to increase crop yields, though it has also led to the inadvertent accumulation of them over time. These accumulations have the potential to disrupt the soil ecological process and subsequently impact the plant community composition. Alien plants always benefit from environmental variability, thus whether the accumulation of fertilizer, plastic, and pesticide in soil promotes the dominance of alien plants in an invaded community. Here, five aliens and co-occurring natives were selected as study materials, and a full factorial experiment was conducted to answer this question. Our study found that microplastics promote the biomass production of native plants at higher nutrient availability while having marginal influence on growth of alien plants. Alien plants exhibited a lower root mass fraction (RMF) with increased nutrient availability and a higher specific leaf area (SLA) in response to the addition of nutrients and microplastics. Pesticide residues in the soil also significantly decreased the root mass fraction of three species, but there was no significant difference between the effects on alien and native species. Overall, our results revealed that alien species adjusted their functional traits more quickly, but native species gained more growth advantages in response to fertilization and microplastics.

Position-specific kinetic isotope effects for nitrous oxide: a new expansion of the Rayleigh model

Abstract. Nitrous oxide (N2O) is a potent greenhouse gas and the most significant anthropogenic ozone-depleting substance currently being emitted. A major source of anthropogenic N2O emissions is the microbial conversion of fixed nitrogen species from fertilizers in agricultural soils. Thus, understanding the enzymatic mechanisms by which microbes produce N2O has environmental significance. Measurement of the 15N / 14N isotope ratios of N2O produced by purified enzymes or axenic microbial cultures is a promising technique for studying N2O biosynthesis. Typically, N2O-producing enzymes combine nitrogen atoms from two identical substrate molecules (NO or NH2OH). Position-specific isotope analysis of the central (Nα) and outer (Nβ) nitrogen atoms in N2O enables the determination of the individual kinetic isotope effects (KIEs) for Nα and Nβ, providing mechanistic insight into the incorporation of each nitrogen atom. Previously, position-specific KIEs (and fractionation factors) were quantified using the Rayleigh distillation equation, i.e., via linear regression of δ15Nα or δ15Nβ against [-fln⁡f/(1-f)], where f is the fraction of substrate remaining in a closed system. This approach, however, is inaccurate for Nα and Nβ because it does not account for fractionation at Nα affecting the isotopic composition of substrate available for incorporation into the β position (and vice versa). Therefore, we developed a new expansion of the Rayleigh model that includes specific terms for fractionation at the individual N2O nitrogen atoms. By applying this Expanded Rayleigh model to a variety of simulated N2O synthesis reactions with different combinations of normal, inverse, and/or no KIEs at Nα and Nβ, we demonstrate that our new model is both accurate and robust. We also applied this new model to two previously published datasets describing N2O production from NH2OH oxidation in a methanotroph culture (Methylosinus trichosporium) and N2O production from NO by a purified Histoplasma capsulatum (fungal) P450 NOR, demonstrating that the Expanded Rayleigh model is a useful tool in calculating position-specific fractionation for N2O synthesis.

Nitrous oxide emissions and yields from potato production systems as influenced by nitrogen fertilization and irrigation: A meta‐analysis

AbstractPotato (Solanum tuberosom) is a globally significant crop in relation to the scale of its consumption, being the third most consumed worldwide. The overall sustainability of global agriculture is increasingly of concern, specifically in relation to increasing anthropogenic emissions of the greenhouse gas nitrous oxide (N2O) emissions from nitrogen fertilizer additions to croplands and its contribution to climate change. Against this backdrop, a meta‐analysis of 119 experimental comparisons from 18 studies—spanning 19 study sites in 10 countries—was employed to investigate the impact of irrigation, cumulative water input, N fertilizer application rate, soil pH, and soil texture on cumulative N2O fluxes and tuber yield in potato production. Compared to non‐fertilized controls, N2O emissions from fertilized potato production decreased by 34% when irrigation provided 61%–90% of total water input (corresponding to averages of 321–473 mm). Likewise, N2O emissions increased by 53% with 200–475 mm seasonal water input and by 37% with N fertilization rates of 101–200 kg N fertilizer ha−1. Furthermore, soil pH between 7.1 and 7.5 reduced emissions by 6%, while medium‐textured soils showed an increase of 2%. Conversely, tuber yields from fertilized potato production were comparatively maximized under 31%–60% of water input as irrigation (7%) and 751–1025 mm cumulative seasonal water input (28%). Alongside 201–300 kg N fertilizer ha−1 (97%), soil pH of 7.1–7.5 (48%), and in coarse‐textured soils (49%). Overall, these findings underscore the importance of considering irrigation and N fertilization options specifically in optimizing potato production for reduced N2O emissions and enhanced tuber yield.

Unlocking Potential: The Role of Zinc Fortification Combating Hidden Hunger and Enhancing Nutritional Security

Micronutrient shortage is rapidly becoming apparent have drawn more attention in the cultivation of crops. The main causes of this deficit are the introduction of high-yielding varieties, an intensified cropping strategy, and advanced irrigation systems etc. A further aspect contributing to this issue is the increased use of high analysis chemical fertilizers instead of organic plant nutrition (composts, farmyard manure, etc.). Most countries have acute shortages of micronutrients due to the significant depletion of soil reserves caused by current agricultural production technologies. In order to increase both the quantity and quality of crops, micronutrients are crucial. Through the integration of agronomic, breeding and transgenic techniques, researchers seek to strengthen the zinc concentration in field crops, so improving their nutritional value and mitigating the risk of zinc deficiency in human diets. The availability and absorption of micronutrients in crops are improved by agronomic techniques such as foliar spraying, and soil fertilizer treatment including organic amendments. Meanwhile, biofortification of vegetable and fruit crops has also been achieved by transgenic and breeding strategies. In other hand, Rhizobacteria-based biofortification, Chelated Zn biofortification, nutri-priming are also important techniques in Zinc fortification programs to ensure food security and nutritional quality, bio-fortification of micronutrients in crops is vital. In addition, bio-fortification improved quality and crop output, reducing hidden hunger and demonstrating that it was a viable and economical approach. The present review addresses several aspects of zinc insufficiency in human populations, including public health and socioeconomic issues, bio-fortification and ferti-fortification studies, and future efforts to mitigate zinc deficiency in soil and the population at large.

The Jyndevad Experiment: Revealing long-term interactions between liming and phosphorus fertilization in a coarse sand soil

The Jyndevad field experiment, initiated in 1942 on a coarse sand soil in South of Denmark, explores the effect of four liming levels (0, 4, 8 and 12 Mg lime ha−1). These were in 1944 combined with two levels of mineral phosphorus (P) fertilizer (0 and 15.6 kg P ha−1 year−1), with or without a high initial dose of 156 kg mineral P ha−1. This study assesses interactions between liming and P fertilization on soil pH, Olsen-P contents and barley yields covering the last three decades. Annual P application improved barley yield regardless of liming, but the optimal liming level differed from year to year. This emphasizes the need for long-term field experiments to detect the complex interactions between liming and P availability on crop performance. The initial high P dose in 1944 and annual P fertilization increased Olsen-P contents in soil. The unlimed soil with pH(CaCl2) values below 4 had the highest Olsen-P content. The Jyndevad Experiment now harbors wide gradients in soil P (Olsen-P contents: 9–82 mg P kg−1 soil) and pH (3.6–6.9), providing a unique research platform for future studies on interactions between liming and P fertilization on coarse sand soils. We present a selection of studies that have used the Jyndevad Experiment to illustrate the research potential of the experiment.

Innovative Tillage Practices to Establish Productive and Sustainable Forage Production Systems in Degraded Alfalfa Pastures in Semiarid Regions

ABSTRACTTillage management practices play a critical role in maintaining sustainable forage production systems in degraded alfalfa (Medicago sativa L.) pastures. However, climate change leads to the precipitation exhibits greater variability, the impacts of tillage practices on alfalfa productivity and forage quality as well as the relationships between water consumption and soil properties remain poorly understood. The field trial conducted from 2018 to 2020 aimed to investigate the impacts of different tillage treatments (i.e., no tillage [CK], strip subsoiling tillage [ST], strip rotary tillage [RT], and strip rotary tillage after strip subsoiling [SRT]) on soil properties, water use efficiency (WUE), and forage productivity. Compared with CK, tillage practices significantly increased forage biomass and crude protein yield (CPY), particularly in the case of the SRT treatment, in which the increase was 20.8% and 25.3% higher, respectively (p &lt; 0.05). Meanwhile, the net income in the SRT treatment exhibited the greatest value (US $1922.0 ha−1), showing a 17.0% increase compared with that in the CK treatment. The relationship of soil structure and crop water consumption became evident when tillage practices were applied in the degraded alfalfa pasture. The soil bulk density under the ST, RT, and SRT treatments decreased by 6.9%, 5.4%, and 8.6%, whereas the soil porosity increased by 8.6%, 6.7%, and 10.7% in the 0–60 cm soil layer, respectively (p &lt; 0.05). Furthermore, the soil water content at a depth of 0–60 cm increased by 12.1% in the SRT treatment compared with the CK treatment at the harvesting stage, and the SRT treatment obtained the highest WUE of dry matter (16.9 kg ha−1 mm−1) and precipitation use efficiency of dry matter (15.8 kg ha−1 mm−1). In addition, total nitrogen in the ST, RT, and SRT treatments increased significantly by 21.4%, 11.1%, and 27.0%, respectively, and soil organic carbon in the ST, RT, and SRT treatments also increased significantly by 5.5%, 3.3%, and 10.4%, respectively, compared with those in the CK treatment (p &lt; 0.05). Our study has demonstrated that tillage practices can optimize soil structure, improve water utilization, and increase soil fertilizer for enhancing forage productivity. The SRT practice could be a preferable approach for sustainable agricultural production of degraded alfalfa grassland in the semiarid region of China.

Potential to Ensure Safe Production of Water Spinach in Heavy Metals-Contaminated Soil by Substituting Chemical Fertilizer with Organic Fertilizer

Organic fertilizers are widely used to improve soil quality. However, their potential for ensuring the safe production of vegetables in soils with varying levels of heavy metals pollution remains inadequately explored. Here, we conducted a pot experiment to investigate the effects of substituting chemical fertilizers with organic fertilizer on the HMs accumulation in water spinach by simulating soils with different levels of HMs pollution. The results showed that the organic fertilizer significantly increased the soil pH, cation exchange capacity (CEC), and organic matter (OM). Furthermore, it led to a reduction in the soil DTPA–Cd and DTPA–Pb levels by 3.3–20.6% and 22.4–47.3%, respectively, whereas the DTPA–As levels increased by 0.07–7.7 times. The organic fertilizer effectively reduced the Cd and Pb content in water spinach below the safety limits when the added Cd content in the soil was less than 2 mg/kg and the Pb content was equal to or less than 90 mg/kg. However, its efficacy in reducing As accumulation in water spinach was limited, emphasizing the need for caution when using organic fertilizers in As-contaminated soils. Our results provide valuable insights for the scientific and precise utilization of organic fertilizers, thereby contributing to the safe production of vegetables.

Effect of Different Fertilization Strategies on Infestation of Brown Wheat Mite and Wheat Productivity

The brown wheat mite, Petrobia tritici, poses a significant threat to wheat fields. While fertilizers can increase crop productivity, imbalanced application may exacerbate plant susceptibility to pests. This study aimed to evaluate the impact of various NPK fertilization programs on P. tritici infestations over two consecutive cropping seasons. The results revealed significant differences in mite infestation among the treatment groups (p &lt; 0.001). The lowest populations (1.1 and 3.0 mites/leaf) were observed in the treatments sprayed with phosphoric acid (at 0.75 and 1.00 cm/L), where the infestation appeared approximately 120 days after sowing; in contrast, it appeared early at 75 days in the other treatments. Conversely, treatments lacking potassium fertilizer presented the greatest degree of mite injury levels (49.5–57.7 mites/leaf). Although these treatments provided moderate leaf nutrition and crop yield, the highest nutritional content and total yield (10.49 and 9.71 1 t/ha for the two years) were observed in the treatment that received 224:70:100 kg fad−1 commercial fertilizers (=178:25:114 kg ha−1 NPK units) as soil fertilization, which was followed by the treatment with a foliar application of phosphoric acid (1.00 cm/L) with a total yield of 9.34 and 8.53 1 t/ha for the two years. In this treatment, the P. tritici density was moderately high at 9.40 and 6.32 mites/leaf over the two years, respectively. The consistency of P. tritici density and total yield ranking across both years indicated reliable estimates of the impact of fertilization. This study suggests that potassium sulfate application is crucial for reducing P. tritici density and that foliar phosphoric acid application instead of soil application reduces the number of P. tritici and delays its occurrence.

Recovering of Olive Groves Infected by Xylella fastidiosa subsp. pauca in Apulia (Italy) Through a Sustainable Management Strategy

Abstract Xylella fastidiosa subsp. pauca , listed as a quarantine bacterium in the European Union, has spread in Salento (Apulia, Southern Italy) landscape causing severe damage to the olive cultivation. X. fastidiosa is the causal agent of the “olive quick decline syndrome” (OQDS). Through a series of multidisciplinary studies, it has been possible to assess and set up an effective management strategy for maintaining the traditional olive germplasm of Salento. For this aim, a systemic biocomplex containing zinc (4%), copper (2%) and citric acid is sprayed to the tree canopy, once per month, from spring to early autumn. The strategy also includes sustainable vector control through agronomical techniques as well as the regular tree pruning and soil fertilization. Quantitative real-time polymerase chain reaction (PCR) assessments showed a significant reduction of X. fastidiosa subsp. pauca concentration in the xylem tissue of the leaves upon the treatments, thus allowing the olive trees to normally yield. Both 1 H-NMR metabolomic and mass-spectrometry lipidomic analyses of leaf extracts revealed the occurrence of biomarkers linked to the disease or tree restoration. After the spray treatment, a rapid re-programming in the metabolic tree activity has been observed. Multi-scale satellite imagery monitoring confirmed the robustness of the strategy for several years in both experimental and productive olive groves. Currently, the strategy is applied in many olive groves of Salento. Some aggressive fungal species belonging to the Neofusicoccum genus have been found to be associated with olive trees that show symptoms very similar to OQDS and that are also co-infected by X. fastidiosa subsp . pauca . Information © The Author 2024

Optimization of an aerated fertilizer irrigation application scheme for tomato photosynthesis, yield and quality in Xi'an, China

Soil aeration is known to alleviate root zone hypoxia, improve root growth environment, and enhance crop yield and water and fertilizer use efficiency. However, the specific effects of coupled soil aeration and fertilization on photosynthesis, chlorophyll content, yield, and quality of tomato remain unclear. To address this knowledge gap, greenhouse experiments were conducted for 2 years on tomato in Xi'an, China. In preliminary experiments, it was observed that the combination of venturi and two dispersers treatments could enhance air transfer distance within the drip irrigation system over a range of 0–25 m. Subsequently, in the planting experiments, 3 levels of aeration (A) were established: A1 (no aeration), A2 (7.50 % air-to-water ratio), and A3 (15.00 % air-to-water ratio), along with 3 fertilizer (F) levels: F1 (no additional fertilizer), F2 (N- P2O5-K2O fertilizer application rate of 120-60-78 kg ha−1), and F3 (N- P2O5-K2O fertilizer application rate of 240-120-150 kg ha−1). The study revealed that aeration significantly increased the photosynthetic rate, chlorophyll content, and dry matter content of tomatoes, resulting in a substantial improvement in both yield and quality. Additionally, aeration was found to enhance fertilizer use efficiency (FUE) and water use efficiency (WUE). In 2021, fertilizer increased the Chl. b content and improved photosynthesis, ultimately enhancing the yield, vitamin C, and total soluble sugars in tomatoes. Under the A3F1 treatment, FUE was the highest, while WUE was the highest under the A3F3 treatment. The A1F1 treatment resulted in the lowest tomato yield, with 37.22 t/ha in 2021 and 39.85 t/ha in 2022. The A3F3 treatment consistently produced the highest yield, achieving 50.53 t/ha in 2021 and 51.11 t/ha in 2022. The A1F3 treatment exhibited the highest return on investment. These findings are of paramount importance for optimizing tomato cultivation practices, improving fertilizer efficiency, and promoting sustainable agricultural production.

Biochar Production From Plastic‐Contaminated Biomass

ABSTRACTAnaerobic digestion and composting of biowastes are vital pathways to recycle carbon and nutrients for agriculture. However, plastic contamination of soil amendments and fertilizers made from biowastes is a relevant source of (micro‐) plastics in (agricultural) ecosystems. To avoid this contamination, plastic containing biowastes could be pyrolyzed to eliminate the plastic, recycle most of the nutrients, and create carbon sinks when the resulting biochar is applied to soil. Literature suggests plastic elimination mainly by devolatilization at co‐pyrolysis temperatures of &gt; 520°C. However, it is uncertain if the presence of plastic during biomass pyrolysis induces the formation of organic contaminants or has any other adverse effects on biochar properties. Here, we produced biochar from wood residues (WR) obtained from sieving of biowaste derived digestate. The plastic content was artificially enriched to 10%, and this mixture was pyrolyzed at 450°C and 600°C. Beech wood (BW) chips and the purified, that is, (macro‐) plastic‐free WR served as controls. All biochars produced were below limit values of the European Biochar Certificate (EBC) regarding trace element content and organic contaminants. Under study conditions, pyrolysis of biowaste, even when contaminated with plastic, can produce a biochar suitable for agricultural use. However, thermogravimetric and nuclear magnetic resonance spectroscopic analysis of the WR + 10% plastics biochar suggested the presence of plastic residues at pyrolysis temperatures of 450°C. More research is needed to define minimum requirements for the pyrolysis of plastic containing biowaste and to cope with the automated identification and determination of plastic types in biowaste at large scales.

VERMICULTURE AND VERMICOMPOSTING: TWIN EARTHWORM TECHNOLOGIES, SUITABLE FOR HOUSEHOLDS AND SMALLHOLDER FARMERS TO CONVERT WASTES TO WEALTH – A NARRATIVE REVIEW

Many smallholder farmers in developing countries face interconnected challenges, including poor soil fertilisation, low agricultural output, and inefficient conversion of agricultural wastes into biofertilisers, all of which can be sustainably addressed through vermiculture and vermicomposting—twin earthworm-based technologies. This review aims to explore vermiculture and vermicomposting, their interconnections, and key optimisation factors, while also guiding smallholder farmers on setting up simple vermiculture and vermicomposting units using locally sourced materials. A wide literature search was conducted across databases such as Google Scholar, Scopus, and Web of Science, focusing on vermiculture, vermicomposting and earthworm utilisation in waste management. From an initial pool of articles, 35 studies were selected for their relevance, empirical data, and rigorous methodology. Findings show that earthworms' natural behaviours, such as burrowing, soil ingestion, excretion and rapid reproduction, are exploited by vermiculture and vermicomposting to produce both earthworm mass and vermicompost, a sustainable and efficient biofertilizer. Vermiculture focuses on maximising earthworm harvest, with vermicompost as a secondary product, while vermicomposting aims to maximise vermicompost production, often resulting in increased earthworm mass. Vermicomposting units can be constructed from locally available materials, including wood, organic and agricultural wastes, and earthworm food sources, like fermented cow and sheep dung. The review assesses the potential of these technologies for small-scale farms, emphasising their feasibility and benefits in resource-limited settings. Since low agricultural output by smallholder farmers is partly traceable to unaffordable costs of chemical fertilisers, this review will draw attention to the use of vermicompost as a cheap and sustainable alternative

The Role of Deadwood in Forests between Climate Change Mitigation, Biodiversity Conservation, and Bioenergy Production: A Comparative Analysis Using a Bottom–Up Approach

Recent literature highlights the crucial role of deadwood in forests, emphasizing its contribution to biodiversity conservation, soil fertility, climate change mitigation, and bioenergy production. However, managing deadwood presents challenges as decision-makers must balance trade-offs and synergies between these ecological benefits. A participatory approach, incorporating user opinions, can support effective decision-making. This study surveyed 1207 university students from Iran, Italy, and Türkiye to explore their perceptions of deadwood’s role and the potential trade-offs among climate change mitigation, biodiversity conservation, and bioenergy production. Results indicate a high level of awareness among students regarding deadwood’s ecological functions, but preferences vary significantly across cultural and regional contexts. Results show that for students of all three countries, the most important function related to the deadwood in forests is the provision of microhabitats for wildlife, while in second place for Iranian students, there is bioenergy production, and for Turkish and Italian students, soil fertilization. In addition, results highlight that students prefer the management strategies based on leaving both standing dead trees and lying deadwood in the forest. This study reinforces existing literature on deadwood’s importance for biodiversity and underscores the need for informed policies that balance ecological values with practical management considerations.

Biochemical Parameters of Fallow Light Soil Enriched with Sewage Sludge

One way to manage sewage sludge, which is consistent with the assumptions of the European Green Deal, is to use it in agriculture. The study focused on the possibility of using soil enzyme activity and the GMea index (the geometric mean of enzyme activities) in connection with the total organic carbon (TOC) and the total nitrogen (TN) content to assess the quality of fallow light soil after exogenous organic matter (EOM) fertilization. Exogenous organic matter in the form of stabilized municipal sewage sludge was introduced into the soil. The experiment included five variants: one control site and four sites with 30, 75, 150, and 300 Mg ha−1 of sewage sludge added to the soil. The contents of TOC, TN and heavy metals (Zn, Cu, Pb, Cd) in the soil material were assayed. In addition, the activity of soil enzymes, i.e., neutral phosphatase, urease, protease and dehydrogenase, was examined, and the geometric mean of the enzyme activities (GMea index) was calculated. Fertilization of light soil with sewage sludge resulted in an increase in TOC and TN proportionally to the EOM dose. The addition of sewage sludge increased the content of tested heavy metals in the soil and did not exceed the levels considered acceptable. The introduction of sewage sludge contributed to the stimulation of biological life in the soil. This was evidenced by an intensification of soil enzyme activity. However, individual enzymes showed a different response to EOM fertilization, while GMea showed a significant increase in the quality of the fallowed soils as the EOM rate increased to 150 Mg ha−1.

The role of proton excreted by Advenella kashmirensis DF12 during ammonium assimilation in phosphate solubilization.

Phosphate-solubilizing bacteria (PSB) can solubilize soil fixed phosphorus (P) to plant available forms. In previous studies, the mechanisms of inorganic phosphate solubilization by PSB mostly focused on the acidolysis of organic acids. Here we screened a highly efficient PSB, Advenella kashmirensis DF12, with the maximum P solubilization of 590 mg L- 1 at 6 days. In addition to its P solubilizing ability, DF12 also showed a tolerance to pH from 5 to 10 and a nitrogen fixation potential. The multiple functions of DF12 and its wide adaptability to various environmental conditions make it a promising biofertilizer candidate. The combined analysis of extracellular metabolites and intracellular metabolome data revealed that the production of organic acid (mainly gluconic acid) is not the only mechanism of P solubilized by DF12, the solubilized P content was not correlated with the gluconic acid concentration but was in a highly significant positive correlation with proton concentration, extrusion of proton during NH4+ assimilation plays a key role in phosphate solubilization. Moreover, the contribution of NH4+ assimilation to phosphorus solubilization is generally present in PSB. Therefore, we proposed that applying ammonium fertilizer in P-deficient soil is more appropriate, it can not only supplement nitrogen fertilizer, but also enhance P use efficiency, which contributes to worldwide fertilizer use reduction and efficiency improvement.