Nutrient Levels Research Articles

The influence of endothelial metabolic reprogramming on the tumor microenvironment.

Endothelial cells (ECs) that line blood vessels act as gatekeepers and shape the metabolic environment of every organ system. In normal conditions, endothelial cells are relatively quiescent with organ-specific expression signatures and metabolic profiles. In cancer, ECs are metabolically reprogrammed to promote the formation of new blood vessels to fuel tumor growth and metastasis. In addition to EC's role on tumor cells, the tortuous tumor vasculature contributes to an immunosuppressive environment by limiting T lymphocyte infiltration and activity while also promoting the recruitment of other accessory pro-angiogenic immune cells. These elements aid in the metastatic spreading of cancer cells and contribute to therapeutic resistance. The concept of restoring a more stabilized vasculature in concert with cancer immunotherapy is emerging as a potential approach to overcoming barriers in cancer treatment. This review summarizes the metabolism of endothelial cells, their regulation of nutrient uptake and delivery, and their impact in shaping the tumor microenvironment and anti-tumor immunity. We highlight new therapeutic approaches that target the tumor vasculature and harness the immune response. Appreciating the integration of metabolic state and nutrient levels and the crosstalk among immune cells, tumor cells, and ECs in the TME may provide new avenues for therapeutic intervention.

Effects of Sugarcane/Peanut Intercropping on Root Exudates and Rhizosphere Soil Nutrient.

Intercropping can enable more efficient resource use and increase yield. Most current studies focus on the correlation between soil nutrients and crop yield under intercropping conditions. However, the mechanisms related to root exudates and soil nutrients remain unclear. Therefore, this study explored the correlation between rhizosphere soil nutrients and root exudates in sugarcane/peanut intercropping. Root extracts, root exudates, rhizosphere soil enzyme activities, and soil nutrients were analyzed and compared in monocultured and intercropped peanut and sugarcane at different growth stages. The root metabolites were annotated using the Kyoto Encyclopedia of Genes and Genomes pathways to further identify the connection between soil nutrients and root exudates. The effects of intercropping differed in peanut and sugarcane at different growth stages, and the difference between podding and pod-filling stages was significant. Intercropping generally had a great effect on peanut; it not only significantly increased the organic acid, soluble sugars, and phenolic acids in root exudates and extracts from peanuts, but also significantly increased rhizosphere soil enzyme activities and soil nutrient levels. Intercropping peanuts promoted fumaric acid secretion from roots and significantly affected the metabolic pathways of alanine, aspartate, and glutamate. Sugarcane/peanut intercropping can increase root exudates and effectively improve soil nutrients. The changes in soil nutrients are closely related to the effects of fumaric acid on alanine, aspartate, and glutamate metabolism.

Effect of Nutrient Management During the Nursery Period on the Growth, Tissue Nutrient Content, and Flowering Characteristics of Hydroponic Strawberry in 2022

The objective of a strawberry nursery is to produce numerous runners and improve the quality of the runner plants, ensuring their uniformity and health. About 80% of the strawberry nurseries in Wanju-gun, Republic of Korea, are cultivated by the growers themselves, which results in variations in the cultivation techniques. Different methods are employed to reduce the nitrogen levels to promote floral bud initiation in the later nursery stage, and these methods vary between farms. This study was conducted on the ‘Sulhyang’ cultivar (Fragaria × ananassa Dutch. cv. Sulhyang) to measure the nutrient content in runner plants obtained from eight growers using various cultivation methods, supply EC levels, nutrient solution termination times, etc., and to correlate the nutrient levels with floral bud initiation during the nursery period. Four investigations were conducted at 15-day intervals from Julian day 214 (2 August) to Julian day 259 (16 September) in 2022, focusing on nutrient management during the nursery period, runner plant growth, petiole nitrate nitrogen content (NO3-N), and soluble solid content (SSC). The NO3-N content decreased, and the SSC/NO3-N ratio increased near the transplanting period, as assessed using a rapid inorganic nutrient diagnostic device. The proportion of runner plants that had advanced to stage 3 or above in floral bud initiation was investigated using a stereomicroscope. As a result, differences in the percentage of floral bud initiation were confirmed based on the varying nutrient management among the farms. In this study, on Julian day 243 (31 August 2022), there was a strong negative correlation (r = −0.86, r2 = 0.73) between the NO3-N content in the runner plants and the percentage of floral bud initiation. These results emphasize the importance of nutrient management during the nursery period, especially for strawberry self-propagating growers, and demonstrate a strong correlation between nutrient content and floral bud initiation in strawberries.

Methane seepage leads to a specific microplastic aging process in the simulated cold seep environment

Marine microplastics pose a significant threat to ecosystems, and deep-sea regions serve as critical sinks for these pollutants. Among these regions, cold seeps harbor relatively high concentrations of microplastics. However, research on the aging of microplastics under low-temperature, dark, methane-abundant, and high-pressure conditions remains limited. Seawater and sediment were collected from various Haima cold seepage sites to simulate seepage environments in 200-mL high-pressure reactors. Four types of microplastics at high concentrations (approximately 10 %) were cultured and monitored over two months to explore how they aged. The key findings are as follows: (1) Compared to areas of weak seepage, methane seepage accelerated microplastic aging, as evidenced by increased surface roughness, enhanced C-O and (CO)-O bond formation, increased microbial colonization, and reduced contact angles. (2) Microplastic aging is more pronounced in sediments than in seawater, with biodegradable polylactic acid (PLA) exhibiting the most significant aging characteristics and carbon contribution. (3) Aged microplastics induce greater disturbances in inorganic nutrient levels than in organic matter, impacting nitrogen cycle processes involving nitrate, nitrite, and ammonium. This study results reveal the fundamental aging characteristics of microplastics in extremely deep seas and highlight their potential ecological effects.

Effects of Straw and Green Manure Addition on Crop Yield, Soil Properties and CH4 Emissions: A Meta-Analysis

The incorporation of organic amendments is widely acknowledged for its capacity to enhance soil fertility and boost crop productivity. However, whether the addition of organic amendments can improve soil quality and crop production, simultaneously causing methane emissions in paddy fields, deserves further investigation. In this meta-analysis, the effects of different organic amendments on soil nutrient levels, rice yield and CH4 emissions were evaluated in paddy fields based on 328 observations from 77 field trial studies. Our results revealed that the addition of organic amendments significantly increased soil organic carbon (9.47%), microbial biomass carbon (21.13%), microbial biomass nitrogen (28.91%), urease (25.07%) and β-glucosidase (24.41%). Moreover, straw addition significantly increased the CH4 emissions by 152.68% and rice yield by 7.16%; green manure addition significantly increased CH4 emissions by 71.62% and rice yield by 10.09%, respectively. Although both increased the CH4 emissions, green manure had the ability to improve the availability of N, which could improve rice uptake. The regression results showed that the variation in crop yield, soil nutrients and CH4 emissions are influenced through the types and quality of organic amendments. Overall, this study suggests that organic amendments are beneficial in maintaining soil quality and improving rice yield, whereas it also increased the CH4 emissions. These meta-analysis results may provide some references for optimizing organic amendments incorporated into the soil to sustain soil fertility and crop production while mitigating soil constraints and methane emissions.

The Contribution of Siliceous Plankton to Vertical Export Flux in the Eastern Mediterranean: A Comparative Study of the North Aegean, Cretan, and Ionian Seas

This study investigates the intricate dynamics of siliceous plankton species within the open marine regions of the Greek Seas, focusing on their seasonal and spatial variability. For this purpose, vertical export fluxes of diatoms (DtF), silicoflagellates (SF), and radiolaria (RF) were analyzed in three sediment trap time series obtained from the North Aegean, Cretan, and Ionian Seas. Special attention was given to diatom assemblages, resulting in the estimation of the DtF community structure and diversity for each studied site. Diatom flux values reached 353.9 × 103 valves m−2 day−1, 77.7 × 103 valves m−2 day−1, and 42.4 × 103 valves m−2 day−1 in the North Aegean, Ionian, and Cretan Seas, respectively. SF maxima were 1309.8 × 103 skeletons m−2 day−1 in the North Aegean Sea, 35.2 × 103 skeletons m−2 day−1 in the Ionian Sea, and 11.9 × 103 skeletons m−2 day−1 in the Cretan Sea (South Aegean Sea). RF values reached 13.9 × 103 radiolaria m−2 day−1, 11.9 × 103 radiolaria m−2 day−1, and 5.4 × 103 radiolaria m−2 day−1 in the North Aegean, Ionian, and Cretan Seas, respectively. The North Aegean Sea exhibited significantly higher mean total fluxes, particularly for diatoms, driven by the north-to-south oligotrophy gradient, which was influenced by riverine inflows and the nutrient-rich Black Sea water. In the Cretan and Ionian Seas, convective mixing and atmospheric deposition, especially during increased rainfall (precipitation) events, were identified as primary drivers for the increased siliceous plankton fluxes recorded in the late winter–spring months. Diatom communities were dominated by Naviculales and Fragilariales; the prevalence of the former in the North Aegean Sea is likely linked to the higher nutrient levels in its upper photic zone, as Naviculales includes species with a high affiliation to nutrient enrichment.

Soil Physico-chemical Responses to Integrated Nutrient Management in Lentil Intercropped with Bhimal (Grewia optiva) in Agroforestry vs. Open Systems

The growing concern over health risks associated with the heavy use of chemical fertilizers and pesticides in India, which have been linked to rising cancer cases, underscores the need for sustainable agricultural practices. Integrated Nutrient Management offers a promising solution to enhance soil fertility and support crop health, especially for lentil cultivation within agroforestry systems. This study, conducted at Dr. Y. S. Parmar University of Horticulture and Forestry in Nauni, Solan, Himachal Pradesh, examined the effects of INM on the soil’s physical and chemical properties when lentils were intercropped within a Grewia optiva (Bhimal) agroforestry system in the mid-hills region of Himachal Pradesh. The experiment evaluated various combinations of organic and inorganic fertilizers, including T1: Recommended Dose of Fertilizer, T2: Farmyard Manure, T3: Vermicompost, T4: Goat Manure, T5: 50% Recommended dose of fertilizer + 50% Farm yard manure, T6: 50% Recommended dose of fertilizer + 50% Vermicompost, T7: 50% Recommended dose of fertilizer + 50% Goat Manure, and T8: Control. These treatments were applied in plots both under the Bhimal-based agroforestry system (S1) and in open field conditions (S2), with three replications per treatment following a factorial randomized block design. Key physical parameters such as bulk density, particle density, porosity, and soil moisture were measured alongside chemical properties, including soil pH, electrical conductivity, organic carbon content, and the availability of nitrogen, phosphorus, and potassium. Data collected over two years was analyzed using R Statistical Software, revealing that INM significantly improved soil properties in the agroforestry system compared to the control. Notably, 100% FYM emerged as the most effective treatment, enhancing soil porosity, moisture, pH, and nutrient availability (N, P, and K). Improvements in soil structure and nutrient levels were particularly evident in the second year, positively impacting lentil growth and yield. The study highlights the potential of INM to promote sustainable, chemical-free agriculture in hilly areas, offering valuable recommendations for farmers and policymakers focused on sustainable agriculture. Specifically, 100% FYM is recommended for improving soil health and crop productivity in the mid-hill region of Himachal Pradesh, providing a model for similar agro-ecological zones aiming to reduce chemical inputs and support human health.

Effects of Fresh and Composted Azolla on Soil Chemical Properties

The rise in chemical fertilizer use in Malaysia raises concerns about soil degradation and potential long-term yield reductions, highlighting the importance of using organic matter for soil restoration. Azolla has been extensively studied as an alternative soil amendment due to its high nitrogen and nutrient content, as well as its rapid growth. However, the effects of fresh and composted Azolla amendments on soil chemical properties are not yet fully understood. A soil incubation study was thus conducted to determine the effects of fresh and composted Azolla on soil chemical properties over a 3-month incubation period. The soil treatments consisted of non-amended soil (control); fresh Azolla at 3, 6, and 9% w/w; and composted Azolla at 1, 2, and 3% w/w, with soil water holding capacity maintained at 55% throughout the incubation period. The collected soil samples were analyzed for soil pH and electrical conductivity (EC), total carbon (C) and nitrogen (N), available phosphorus, exchangeable bases—potassium (K), calcium, and magnesium, using inductively coupled plasma optical emission spectrometry, and cation exchange capacity (CEC). All data were subjected to variance analysis for statistical analysis. The study revealed significant effects of interaction between soil treatments and incubation periods for all soil parameters. At the end of the incubation period, the soil treated with 3% composted Azolla exhibited higher soil EC, total C and N, exchangeable K, and CEC compared to other soil treatments. The 3% fresh Azolla treatments were also observed to improve the soil’s exchangeable calcium by the end of the incubation period. In conclusion, 3% composted Azolla is best to help restore soil nutrient levels for crop uptake.

The Synergistic Impact of a Novel Plant Growth-Promoting Rhizobacterial Consortium and Ascophyllum nodosum Seaweed Extract on Rhizosphere Microbiome Dynamics and Growth Enhancement in Oryza sativa L. RD79

This study investigated the combined effects of novel plant growth-promoting rhizobacteria (PGPR)—Agrobacterium pusense NC2, Kosakonia oryzae WN104, and Phytobacter sp. WL65—and Ascophyllum nodosum seaweed extract (ANE) as biostimulants (PGPR-ANE) on rice growth, yield, and rhizosphere bacterial communities using the RD79 cultivar. The biostimulants significantly enhanced plant growth, shoot and root length, and seedling vigour; however, seed germination was not affected. In pot experiments, biostimulant application significantly increased the richness and evenness of bacterial communities in the rhizosphere, resulting in improvements in rice growth and yield, with increases in plant height (9.6–17.7%), panicle length (14.3–17.9%), and seeds per panicle (48.0–53.0%). Notably, biostimulant treatments also increased post-harvest soil nutrient levels, with nitrogen increasing by 7.7–19.2%, phosphorus by 43.4–161.4%, and potassium by 16.9–70.4% compared to the control. Principal coordinate analysis revealed distinct differences in bacterial composition between the tillering and harvesting stages, as well as between biostimulant treatments and the control. Beneficial bacterial families, including Xanthobacteraceae, Beijerinckiaceae, Acetobacteraceae, Acidobacteriaceae, and Hyphomicrobiaceae, increased in number from the tillering to harvesting stages, likely contributing to soil health improvements. Conversely, methanogenic bacterial families, such as Methanobacteriaceae and Methanosarcinaceae, decreased in number compared to the control. These findings highlight the dynamic responses of the rhizosphere microbiome to biostimulant treatments and underscore their potential benefits for promoting sustainable and productive agriculture.

Effect of temperature, nutrients and growth rate on picophytoplankton cell size across the Atlantic Ocean

The cell size of picophytoplankton populations affects their ecology and biogeochemical role, but how different environmental drivers control its variability is still not well understood. To gain insight into the role of temperature and nutrient availability as determinants of picophytoplankton population mean cell size, we carried out five microcosm experiments across the Atlantic Ocean (45°N-27°S) in which surface plankton assemblages were incubated under all combinations of three temperatures (in situ, 3 °C cooling and 3 °C warming) and two nutrient levels (unamended and addition of nitrogen and phosphorus). The overall range of variability in cell volume was 5-fold for Prochlorococcus, 8-fold for Synechococcus and 6-fold for the picoeukaryotes. We observed, in all the treatments and in the control, a consistent trend toward larger mean cell sizes over time for both Prochlorococcus and Synechococcus, which was likely the result of sample confinement. Changes in temperature and nutrient status alone did not cause clear changes in cell size, relative to the control, but the combination of warming and nutrient addition resulted in an increase in Prochlorococcus and Synechococcus cell size. The largest increases in cell volume were associated with slow or negative population net growth rates. Our results emphasize the importance of considering changes in biovolume to obtain accurate estimates of picophytoplankton biomass and suggest that the inverse relationship between growth rate and population mean cell size may be a general pattern in marine phytoplankton.

Abstract PR009: mascRNA directs nutrient-insensitive activation of the LARS-mTOR pathway in breast cancer

Abstract Cellular growth and metabolism are tightly regulated by nutrient availability, yet cancer cells frequently lose these controls, enabling unchecked proliferation even in the absence of sufficient nutrients. While non-coding RNAs are known to regulate metabolic enzyme expression, their direct role in nutrient-sensing pathways in cancer remains unclear. MALAT1-associated small cytoplasmic RNA (mascRNA) is a 61-nucleotide small RNA with a tRNA-like structure, cleaved from the 3’ end of the long non-coding RNA MALAT1. mascRNA has been shown to promote hepatocellular carcinoma proliferation and enhance protein translation in HEK293 cells, though its underlying molecular mechanism is not fully understood. We assessed mascRNA levels in over 70 human breast cancer patient samples using BaseScope assays and found that mascRNA is detectable in the cytoplasm of tumor cells, but not in normal mammary tissues or stromal cells adjacent to tumors. However, the levels of mascRNA varied significantly among patient samples, irrespective of molecular subtypes or tumor stages, suggesting that mascRNA is associated with other aspects of tumor biology. Functional studies in breast cancer cell lines revealed that mascRNA overexpression promotes cell proliferation, invasion, and metabolic pathways linked to ATP generation. Specifically, mascRNA increases basal glycolysis and mitochondrial oxidative phosphorylation and significantly enhances mitochondrial spare capacity, particularly in triple-negative breast cancer (TNBC) cell lines. We also found that mascRNA overexpression activates both mTORC1 and AMPK, indicating a deviation from the normal negative feedback loop between these two pathways. To dissect the molecular mechanism, we performed mascRNA pull-down assays and mass-spectrometric analyses. We identified RNA splicing factors, tRNA-modifying enzymes, and several aminoacyl-tRNA synthetases as mascRNA-interacting proteins. Among these, leucyl-tRNA synthetase (LARS), a component of the multi-tRNA synthetase complex, is known for its non-canonical role in activating mTORC1 at the lysosomal membrane. We found that, in MDA-MB-231 TNBC cells, mascRNA overexpression led to increased LARS localization to the lysosomal membrane where it can activate mTORC1. Interestingly, while control MDA-MB-231 cells responded to glucose and leucine availability to regulate the lysosomal localization of LARS and mTOR, mascRNA- overexpressing cells constitutively maintained LARS and mTOR localization to the lysosome, as well as mTORC1 phosphorylation, regardless of nutrient status. In summary, our data demonstrate that mascRNA aberrantly activates the LARS-mTORC1 axis in breast cancer cells independent of nutrient levels, likely through direct interaction with LARS, promoting its localization to the lysosome. This suggests that mascRNA enables breast cancer cells, and possibly other cancer types, to sustain uncontrolled growth even in nutrient-deprived conditions. Elevated mascRNA levels may thus represent a highly efficient metabolic adaptation of cancer cells. Citation Format: Bohye Park, Joshua K Stone, Steve Lim, Shuko Harada, Erin Ahn. mascRNA directs nutrient-insensitive activation of the LARS-mTOR pathway in breast cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: RNAs as Drivers, Targets, and Therapeutics in Cancer; 2024 Nov 14-17; Bellevue, Washington. Philadelphia (PA): AACR; Mol Cancer Ther 2024;23(11_Suppl):Abstract nr PR009.

Optimizing Nutrient Management for Enhanced Performance in Kadiri Lepakshi Groundnut

The study was conducted to determine the optimal fertilizer levels for Kadiri Lepakshi groundnut. The experiment consists of eight treatments and was laid out in randomized complete block design with three replications. The present investigation was conducted at Integrated Farming System demonstration plot, ZARS, UAS, GKVK, Bengaluru Karnataka, during the summer of 2022 and Kharif 2023. Five plants from the sampling area were randomly selected and observations on growth and yield parameters were recorded at 30, 60 and 90 days after sowing (DAS) and at harvest. The results revealed that among the various nutrient levels, application of 100 % RDF combined with Phosphogypsum @ 750 kg ha-1 and Borax @ 10 kg ha-1 resulted in significantly higher values for plant height (32.95 cm), number of branches per plant (12.60) and dry matter production at harvest. This treatment also led to a substantial increase in the total number of pods per plant (59) and filled pods per plant (48) in groundnut, performing on par with the treatment that included 100% RDF, Gypsum @ 750 kg ha-1 and Borax @ 10 kg ha-1 (with 57 and 44 pods, respectively) when compared to other treatments. The similar trend was observed with respect to pod yield (2327 kg ha-1), kernel yield (1580 kg ha-1), and haulm yield (3594 kg ha-1). So, the application of 100% RDF with Phosphogypsum @ 750 kg ha-1 and Borax @ 10 kg ha-1 significantly enhanced growth attributes (plant height, branches per plant, and dry matter production) and yield parameters (pods per plant, filled pods, pod yield, kernel yield, and haulm yield) in groundnut. This indicates that Phosphogypsum is an effective source of calcium and sulfur for boosting groundnut yield.

Soil test crop response nutrient prescription equations for improving soil health and yield sustainability-a long-term study under Alfisols of southern India.

Enhancing soil health and nutrient levels through fertilizers boosts agricultural productivity and global food security. However, careful fertilizer use is essential to prevent environmental damage and improve crop yields. The soil test crop response (STCR) is a scientific approach to fertilizer recommendation that ensures efficient use, supporting higher crop production while protecting the environment and preserving resources. A long-term field experiment on the STCR approach was initiated in 2017 at the Zonal Agriculture Research Station, University of Agricultural Sciences, Bangalore, India. The experiment aimed to study the impact of STCR-based nutrient prescription along with farmyard manure (FYM) for a targeted yield of soybean (Glycine max), sunflower (Helianthus annuus), dry chili (Capsicum annuum), aerobic rice (Oryza sativa L.), foxtail millet (Setaria italica), okra (Abelmoschus esculentus), and kodo millet (Paspalum scrobiculatum) on yield and changes in soil health in comparison with other approaches of fertilizer recommendation. The results showed a significant and positive impact of the integrated use of fertilizer with FYM based on the STCR approach on the productivity of all the crops and soil fertility. Significantly higher yields of soybean (23.91 q ha-1), sunflower (27.13 q ha-1), dry chili (16.67 q ha-1), aerobic rice (65.46 q ha-1), foxtail millet (14.07 q ha-1), okra (26.82 t ha-1), and kodo millet (17.10 q ha-1) were observed in the STCR NPK + FYM approach at yield level 1 compared to the general recommended dose and soil fertility rating approach. This approach outperformed the standard recommendations, enhancing nutrient uptake and efficiency across various crops. Utilizing the principal component analysis, the soil quality index effectively reflected the impact of nutrient management on soil properties, with the STCR NPK + FYM treatment at yield level 1 showing the highest correlation with improved soil physical and chemical parameters. The STCR approach led to improved yield, nutrient uptake, utilization efficiency, and soil health, thanks to a balanced fertilization strategy. This strategy was informed by soil tests and included factors like crop-induced nutrient depletion, baseline soil fertility, the efficiency of inherent and added nutrients through fertilizers and farmyard manure, and the success of yield-targeting techniques in meeting the nutritional needs of crops.

The Range of the Colonial Microcystis’ Biomass for Shift to Diatom Aggregates Under Aeration Mixing and Low Light

In order to investigate non-cyanobacteria dominance succession from Microcystis blooms, particularly to diatom dominance, an experiment using varying colonial Microcystis biomasses expressed as bulk concentrations of 2.0, 4.0, 6.0, 8.0, 10.0, 12.0, 14.0, 16.0, 18.0, 20.0, 22.0, and 24.0 mL L−1 was undertaken under continuous aeration mixing in a greenhouse during a hot summer where shading had reduced light level by 97%. The results showed that the algal shift process was affected by the initial biomass of the colonial Microcystis, and the algal community diversified. When the Microcystis bulk concentration was between 2.0 and 16.0 mL L−1, the bloom became dominated by diatom Nitzschia palea, which aggregated on the mucilage sheathes of the Microcystis colonies. The diatom density at bulk concentration biomass of 2.0 mL L−1 reached a maximum at 2.8 × 105 cells mL−1 on day 27. When the bulk concentration was at 18.0–24.0 mL L−1, no diatom dominance appeared. The shift from a Microcystis bloom to diatom dominance was affected by the initial Microcystis biomass, and the most suitable bulk concentration biomass for colonial Microcystis was at 2–12 mL L−1, in which the chlorophyll-a level was about from 285 to 1714 μg L−1. The mechanism underlying this algal shift may be that the low light and nutrient levels in the Microcystis bloom promoted diatom aggregation growth on the mucilage sheaths of Microcystis colonies under continuous aeration mixing.

Enzymatic Biosensors: Advanced Tools for Soil and Plant Health Monitoring

Soil health is the potential of the soil to support the productivity of organisms, preserve the environment, and improve the health of plants and animals. Healthy soil is vital for agricultural sustainability and environmental resilience. The presence of high concentrations of toxic chemicals (pollutants and contaminants) in the soil poses a significant risk to human health and the ecosystem. Plant health is influenced by various factors, including the surrounding environment. To minimize constraints such as low nutrient levels, ecosystem contamination/pollution, and pest and disease incidences in crops, and to maximize productivity and ensure agricultural sustainability, advanced detection and management strategies are urgently needed. Diagnosis, prediction, and monitoring are essential for managing agricultural practices to mitigate these harmful impacts. The development of improved biosensing devices has been driven by the demand for quick, accurate, sensitive, real-time, and fast instruments for screening and identifying contaminants. Specific enzymes are used as the biological sensing element in an enzyme-based biosensor, which is combined with a transducer to transform the signal from the enzymatic reaction into a quantifiable response proportionate to the analyte concentration. Enzymatic biosensors need to possess high specificity, selectivity, reproducibility, stability, a low limit of detection, a low limit of quantification, and a rapid response time. They have a diverse array of uses, such as soil quality monitoring, water monitoring, food quality monitoring, pathogen detection, drug discovery, disease identification, and environmental research.

Low-cost nano biochar: a sustainable approach for drought stress mitigation in faba bean (Vicia faba L.).

This study tends to reach some objectives of the sustainable development goals, which call for responsible consumption and production and climate action. Long-term global food security is affected by drought and the optimal use of water in agricultural areas under climate change scenarios. Our approach aims to amend soil for cultivation under drought stress and improve plant growth to contribute to food security. In this context, a biochar was prepared from peanut shell and thoroughly examined as a soil enhancer for broad bean cultivation during drought stress. The produced biochar exhibited 0.307 g cm-3 bulk density, 9.6 cmol kg-1 cation exchange capacity, -15.5 mV zeta potential, and an average diameter of 21.86 nm. Surprisingly, the application of biochar increased soil water holding capacity and organic matter by 66% and 220%, respectively. Moreover, its application under drought improved plant growth as indicated by stem height, leaf area index, pod number/plant, pod weight, protein level, chlorophyll content, nutrient levels in leaves, and reduced lipid peroxidation and electrolyte leakage. The principal component and factorial analysis of the current study demonstrated correlations between the physiological response of faba bean plants and soil physiochemical parameters after the application of peanut shell-derived biochar. This study presents promising nano biochar that could be an effective sustainable practice for disposing residual materials.

Correlation between Woody Species and Environmental Variables in a Tropical Forest in Central Laos

The tropical forest biome serves as a significant focal point for conservation endeavors. However, understanding the variations in woody plant composition and the underlying driving factors remains limited. The vegetation gradient within Phou Khao Khouay (PKK) National Park in central Laos presents an intriguing environmental model for investigating these patterns. This study, conducted within PKK National Park, aims to classify woody plant communities of three different forest types: mixed deciduous forest (MDF), dry evergreen forest (DEF), and mixed coniferous forest (MCF), utilizing both the phytosociology approach and multivariate analysis. Data from 32 permanent plots (each measuring 50 m × 50 m) were analyzed, revealing 5,477 tree individuals with a diameter at breast height (DBH) ≥ 5 cm, representing 194 woody species from 64 families and 133 genera. The results indicate significant diversity at the family and genus levels, identifying four distinct plant communities and 44 indicator species based on Tichy and Chytry's phi coefficient method. Stability characterizes the MCF forest type, while the stands of DEF and MDF exhibit differentiation into three communities each. Notably, high heterogeneity in species composition and environmental conditions is evident, with elevation and soil nutrient levels (specifically total phosphorus and total potassium) emerging as primary influencers on species coexistence. The study also highlights correlations between woody plant species composition and topographic and soil variables. These findings underscore the importance of identifying microhabitats conducive to growing and conserving woody plant species within PKK National Park for future research and conservation efforts.

Site-specific effects of fertilizer on hay and grain yields of oats: evidence from large-scale field experiments.

Oat (Avena sativa L.) is a valuable crop due to its strong adaptability to marginal environments, making it an important component of agricultural systems in regions where other cereals may not thrive. The application of chemical fertilizer can influence oat hay and grain yield significantly. However, large-scale meta-analytical studies of the size and variability of oat hay and grain yields in response to fertilizer addition are still lacking. Based on 83 studies worldwide, this meta-analysis quantifies the impact of the addition of fertilizer on oat hay and grain yields under varying environmental conditions (e.g., soil nutrient levels, texture, and climate). The results confirmed that the fertilizer application increased oat hay yield by 48.9% and grain yield by 36.2%. This study demonstrated that balanced fertilization with nitrogen, phosphorus, and potassium generally enhances oat hay and grain yield despite large temporal and spatial variations. Boosted regression tree (BRT) models suggest that changes in hay and grain yield were primarily dominated by soil pH and nitrogen fertilizer. The response ratio (the natural logarithm of the mean values of hay yield or grain yield with and without fertilization, respectively) of hay yield declined linearly with soil pH. Elevation was the second most important factor affecting the change in response ratio of hay yield and the third most important factor affecting the change in response ratio of grain yield but climatic conditions were not the dominant factors affecting changes in oat hay or grain yield. Overall, these results will benefit producers considering site-specific fertilization management of oat. They could increase yields and save investment in fertilizer, and help to facilitate the genetic breeding of oat varieties with high nutrient use efficiency. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Rice Production and Nitrogen Use Efficiency by Diverse Forms of Fertilization in Rice-Based Crop Rotation Systems

The rising demand for climate change mitigation has brought attention to agricultural systems focused on carbon farming and reducing emissions. Composting food wastes and livestock manure not only mitigates environmental concerns but also boosts soil fertility and crop yields as an alternative fertilizer. In this experiment, we investigated the effects of different fertilizer types (chemical and organic waste compost) and crop rotations (rice–fallow, rice–Italian ryegrass, and rice–potato) on rice production, nitrogen use efficiency, and soil carbon stocks. In this experiment, soil carbon and nitrogen retention were more influenced by compost nutrient levels than by crop rotation types. Overall, as the nitrogen levels increased, the rice yields improved with both chemical and organic waste fertilizers. Among the crop rotations, the rice–Italian ryegrass rotation showed a higher nitrogen use efficiency. Optimal fertility levels, balancing nitrogen use efficiency, yield, and soil carbon were observed between 523 and 582 kg N ha−1 when combined with specific crop rotations. Moreover, soil total carbon and soil total nitrogen varied among crop rotation systems. Our results indicate that organic waste compost can be a potential alternative to chemical fertilizers, while crop rotations offer a viable approach for maximizing the environmental benefits.

Assessing the impact of tillage practices and nutrient levels on the growth and productivity of Ethopian mustard (Brassica carinata L.) - soybean (Glycine max (L.) Merr.) cropping system

BackgroundAn importance of tillage, inorganic and organic nutrient sources in the mustard - soybean cropping system lies in their ability to enhance soil fertility, improve nutrient availability, optimize crop growth and yield, and promote sustainable agricultural practices. Any cropping system’s sustainability could be increased by implementing better management techniques like zero and reduced tillage with residue retention and better nutrient sources.ResultsA field experiment was conducted for four consecutive seasons (Winter 2019 to Rainy 2021) to compare the two enhanced management practices, zero and reduced tillage to conventional tillage across four levels of nutrient sources: 75 and 100% recommended dose of nitrogen through FYM and 75 and 100% recommended dose of fertilizers through urea, single super phosphate and muriate of potash in a two years experiment. Experiment results were evaluated in terms of nutrient status, profitability and productivity of Mustard-Soybean cropping system. The results show a substantial improvement in yield, nutrient status, and overall yield performance of mustard and soybean when using the full recommended dose of fertilizers combined with reduced tillage and mulching, compared to other treatment methods. The implementation of reduced tillage practices recorded significantly higher yield of mustard and soybean over conventional and zero tillage.ConclusionSystem productivity and profitability i.e. mustard equivalent yield, productivity, gross returns, net returns, profitability and B: C (benefit: cost) was found to be improved with reduced tillage and 100% recommended dose of fertilizer under reduced tillage practices. To enhance cropping system productivity in various sub-humid regions worldwide, farmers can adopt reduced tillage techniques combined with the full recommended dose of fertilizers (100% RDF).