Nutrient Availability Research Articles

Composting and Liquid Formulations: Panacea to Better Yield in Agriculture: A Review

Liquid formulations, including aqueous, oil, and polymer-based products, often use polysaccharides to alter fluid properties. Liquid inoculants offer cost-effective alternatives to solid carriers, particularly benefiting small producers in India by overcoming transportation and processing challenges. Ideal liquid inoculants are non-toxic, low-cost, uniform, nutrient-supplemented, and support rapid microorganism release and growth. Effective formulations stabilize organisms, ensure easy field delivery, protect against environmental factors, and enhance microbial activity. Rich in nutrients and organic matter, compost enhances the texture, structure, and moisture retention of soil, improving soil qualities and crop productivity. It boosts soil enzyme activity and microbial populations, promoting nitrogen fixation and nutrient availability. Organic manure applications increase soil fertility, water retention, and reduce bulk density. Field and horticultural crops, such as potatoes, chillies, and tomatoes, show significant yield improvements with compost, which also suppresses plant diseases and weed populations. These findings underscore the importance of adopting liquid formulations and composting as sustainable agricultural practices.

Phosphorus fertilization promotes carbon cycling and negatively affects microbial carbon use efficiency in agricultural soils: Laboratory incubation experiments

Soil organic carbon (SOC) loss from intensive agriculture represents a major global concern. Consequently, strategies to improve soil management to mitigate or abate SOC losses and enhance carbon (C) sequestration are urgently needed. Nutrient availability, especially nitrogen (N) and phosphorus (P), regulates soil C cycling and storage. While N effects are well studied, less is known about how soil P status and different fertilizer types affects SOC dynamics. This laboratory incubation assessed how two common P fertilizers, diammonium phosphate (DAP) and single superphosphate (SSP), affected microbial activity and C immobilization in the zone of soil directly around the fertilizer granule (prillosphere) across three contrasting agricultural soils (Inceptisol, Vertisol, Alfisol). Soils were amended with DAP or SSP granules and C turnover assessed with 14C-labeled glycine, malic acid or glucose, alongside unfertilized controls. After three weeks, soil pH, electrical conductivity (EC), Olsen-P and microbial C use efficiency (CUE) were measured. DAP increased pH in the Inceptisol (acidic soil), while SSP decreased pH in all soils. Both fertilizers increased EC and Olsen-P, but SSP enhanced Olsen-P more than DAP. Cumulative 14CO2 emissions were 19–20 % higher with P fertilizers compared to the control, with DAP stimulating faster initial C mineralization rates than SSP, except in the Alfisol. P addition reduced microbial CUE by 23–34 % across all soils and substrates versus the unfertilized control. We ascribe this reduction in CUE to an alleviation of nutrient limitation or a fertilizer-induced osmotic stress. The co-addition of N either in DAP or glycine did not alter the P-induced CUE response suggesting that P was more important than N in regulating microbial CUE in these soils. We conclude that P fertilization increased short-term C turnover and may lead to reduced C storage in soil, however, further long-term (>1 year) research is needed to identify optimum P management strategies to minimize C losses in agricultural soils.

Microbial community respiration kinetics and their dynamics in coastal seawater

Oxygen (O2) concentrations in coastal seawater have been declining for decades and models predict continued deoxygenation into the future. As O2 declines, metabolic energy use is progressively channelled from higher trophic levels into microbial community respiration, which in turn influences coastal ecology and biogeochemistry. Despite its critical role in deoxygenation and ecosystem functioning, the kinetics of microbial respiration at low O2 concentrations in coastal seawater remain uncertain and are mostly modeled based on parameters derived from laboratory cultures and a limited number of environmental observations. To explore microbial responses to declining O2, we measured respiration kinetics in coastal microbial communities in Hong Kong over the course of an entire year. We found the mean maximum respiration rate (Vmax) ranged between 560 ± 280 and 5930 ± 800 nmol O2 L−1 h−1, with apparent half-saturation constants (Km) for O2 uptake of between 50 ± 40 and 310 ± 260 nmol O2 L−1. These kinetic parameters vary seasonally in association with shifts in microbial community composition that were linked to nutrient availability, temperature, and biological productivity. In general, coastal communities in Hong Kong exhibited low affinities for O2, yet communities in the dry season had higher affinities, which may play a key role in shaping the relationship between community size, biomass, and O2 consumption rates through respiration. Overall, parameters derived from these experiments can be employed in models to predict the expansion of deoxygenated waters and associated effects on coastal ecology and biogeochemistry.

Effects of Aquatic Physicochemical Parameters Variation on the Phytoplankton Abundance and Diversity in the Babon River, (Semarang, Central Java, Indonesia)

The Babon River is an integral component of Semarang City's drainage system, which is heavily impacted by the influx of waste, leading to elevated water temperatures caused by global warming and decreased pH levels due to acid rain. The two main environmental factors that affect phytoplankton growth and productivity are temperature and nutrient availability. Nutrients can change the balance of the natural food webs of aquatic ecosystems. Meanwhile, metals are toxic and can accumulate in biota tissues. This study examined how nutrients, pH, temperature, and heavy metals in water affected the diversity and abundance of phytoplankton. Water samples and phytoplankton were collected from 7 observation stations representing the upstream, middle, and downstream rivers. Observations at each station were made 3 times in the months of April-May, June-July, and August-September. Temperature and pH were measured in situ with the HORIBA Water Checker. Analysis of nitrate, phosphate, and heavy metals was carried out with an AAS. The results showed that the dominant phytoplankton in the Babon Rivers consisted of Bacillariophyceae, Chlorophyceae, and Cyanophyceae. There is no diversity against all independent variables (temperature, pH, nitrate, phosphate, Cd, Total Cr, Pb concentrations) and dependent variables (number of genera, abundance, and diversity index of phytoplankton) due to the sampling station's location. However, sampling time caused diversity in nitrate, phosphate, Cd, Total Cr, and Pb concentrations, the sampling location effect was more dominant than sampling time, so the results showed that all independent variables did not contribute significantly to the dependent variables.

Analysis of the General Situation of Organic Fertilizer in China

Organic fertilizers are crucial to China's agriculture, significantly enhancing soil fertility and sustainability. Derived from sources like livestock manure, crop residues, and green manure, these fertilizers improve soil structure, water retention, and nutrient availability, thus boosting crop yields and soil health. Despite their benefits, challenges such as variability in quality, application efficiency, and balancing with inorganic fertilizers remain. Government policies and ongoing research are addressing these issues to optimize the use of organic fertilizers and support sustainable agricultural practices.

Modeling the Effects of Temperature and Limiting Nutrients on the Competition of an Invasive Floating Plant, Pontederia crassipes, with Submersed Vegetation in a Shallow Lake.

The potential for a non-native plant species to invade a new habitat depends on broadscale factors such as climate, local factors such as nutrient availability, and the biotic community of the habitat into which the plant species is introduced. We developed a spatially explicit model to assess the risk of expansion of a floating invasive aquatic plant species (FAV), the water hyacinth (Pontederia crassipes), an invader in the United States, beyond its present range. Our model used known data on growth rates and competition with a native submersed aquatic macrophyte (SAV). In particular, the model simulated an invasion into a habitat with a mean annual temperature different from its own growth optimum, in which we also simulated seasonal fluctuations in temperature. Twenty different nutrient concentrations and eight different temperature scenarios, with different mean annual amplitudes of seasonal temperature variation around the mean of the invaded habitat, were simulated. In each case, the ability of the water hyacinth to invade and either exclude or coexist with the native vegetation was determined. As the temperature pattern was changed from tropical towards increasingly cooler temperate levels, the competitive advantage shifted from the tropical FAV to the more temperate SAV, with a wide range in which coexistence occurred. High nutrient concentrations allowed the coexistence of FAV, even at cooler annual temperatures. But even at the highest nutrient concentrations in the model, the FAV was unlikely to persist under the current climates of latitudes in the Southeastern United States above that of Northern Alabama. This result may have some implications for where control efforts need to be concentrated.

Assessment of soil chemical characteristics in the context of Bangladesh: A comprehensive review

This study presents a thorough examination of the chemical properties inherent to soil, with a focus on the unique context of Bangladesh. Soil functions are intricately linked to its chemical composition, which plays a vital role in determining agricultural productivity and ecological vitality. The soil within Bangladesh's geographical boundaries is characterized by its richness and fertility, contributing significantly to its agricultural output and overall ecosystem health. By delving into the chemical properties of Bangladeshi soil, this review aims to enhance our understanding of this dynamic ecosystem. Insights gained from this exploration can shed light on factors influencing soil fertility, nutrient availability, and overall ecosystem health, thereby informing strategies for sustainable land management and agricultural practices in Bangladesh and beyond.

An Overview of the Soil Acidity Causes in Ethiopia, Consequences, and Mitigation Strategies

Soil acidity is a serious land degradation problem and worldwide danger, impacting approximately 50% of the world's arable soils and limiting agricultural yield. Soil acidification is a complicated series of events that lead to the production of acidic soil. In its widest sense, it can be defined as the total of natural and human processes that reduce the pH of soil solutions. Soil acidity affects around 43% of agricultural land in Ethiopia's humid and sub humid highlands. The main objective of this seminar is to highlight different literatures on the concepts of soil acidity and to give a wealth of knowledge on the causes of soil acidity, the effects it has on agricultural production, and management strategies for reducing soil acidity and raising crop yield. Acid soils in western Ethiopia are mostly caused by topsoil erosion caused by heavy rains and high temperatures. This results in the loss of organic matter and the leaching of exchangeable basic cations (Ca<sup>2+</sup>, Mg<sup>2+</sup>, Na<sup>+</sup>, and K<sup>+</sup>). Because ammonium-based fertilizers are easily converted to nitrate and hydrogen ions in the soil, they play a significant role in acidification. One of the reasons of soil acidity is inefficient nitrogen usage, which is followed by alkalinity exports in crops. Soil acidity in Ethiopian highlands is mostly caused by the clearance of crop residues, continuous crop harvest without sufficient fertilization, cation removal, and usage of acid-forming inorganic fertilizers. Acid soil reduces nutrient availability and produces Al and Mn toxicity. In addition to these effects, soil acidity may rapidly degrade soil physicochemical qualities such as organic carbon (OC), cation exchange capacity (CEC), soil structure, porosity, and texture. Liming, the use of organic materials as ISFM, and the adoption of crop types that are resistant to Al toxicity are all alternatives for correcting acid soils. Liming can minimize toxicity by lowering concentrations, improving the availability of plant nutrients like P, Ca, Mg, and K in the soil, and reducing heavy metal solubility and leaching. Application of organic matter has a liming impact because of its abundance in alkaline cations (such Ca, Mg, and K) that were released from OM during mineralization. The pH of the soil is raised by soil organic matter, which helps with soil acidity supplements.

Multi-scale hybrid modeling of plant growth in response to environmental conditions and soil nutrients availability

Crop modeling plays a crucial role in agriculture, aiding our understanding and prediction of crop growth and yield in diverse environmental conditions. This study aims to develop a comprehensive mathematical model describing plant growth in response to environmental conditions and soil nutrient availability. To achieve this, we relied on a field experiment with lettuce plants under varying environmental conditions. Employing growth models such as logistic, Gompertz, Aikman & Scaife, and Scaife, Cox & Morris, we assessed the influence of time, day-degrees, and effective-day-degrees across different plant densities and during distinct periods throughout the year. In general, describing plant growth in terms of day-degrees or effective-day-degrees yielded an improved model fit and more precise estimations of growth parameters. As a result, we described the growth of plant length in terms of effective-day-degrees instead of time in the equations of the Bessonov-Volpert system. Additionally, we modified the equation describing plant length growth using previously fitted functions. By incorporating these adjustments, we characterized the one-dimensional growth of plant weight under varying environmental conditions without branching, using the Bessonov-Volpert model. This study contributes valuable insights into crop modeling techniques, refining our understanding of optimizing plant growth under different environmental conditions.

Ecosystem Size Drives Patterns and Control Mechanisms of Mixotrophs Success Across Tropical Lakes: A Large-Scale Assessment of the Grand Écart Hypothesis

Mixotrophy, a physiological trait combining autotrophy and heterotrophy in one organism, significantly contributes to energy and matter transfer in aquatic ecosystems. However, understanding how environmental factors influence mixoplankton success across freshwater ecosystems has been uncertain. The grand écart hypothesis (GEH) posits that light and nutrient availability are key components of mixotrophs' niche, suggesting that ecosystem properties determine opposing gradients of light and nutrients, creating environmental filtering for mixotrophs. We hypothesized that ecosystem size, a property of lake ecosystems, mediates the prevalence of patterns and control mechanisms predicted by the GEH on mixoplankton relative biomass (MRB). Using data from 98 tropical lakes, we demonstrated that lake size mediates the inverse relationship between light and nutrient availability across ecosystems. Larger lakes have more light but low nutrients, while smaller lakes have more nutrients but greater shading. Light availability better explains MRB in small lakes, and nutrients better explain MRB in large lakes, with MRB values being higher in small lakes, with secondary influence from zooplankton herbivory. Our results validate the GEH as a significant framework for explaining patterns and control mechanisms of mixoplankton across tropical lakes. This study highlights the significance of lake size as an ecosystem property that generates opposing light and nutrient gradients, further emphasizing its importance for understanding mechanisms regulating freshwater phytoplankton community structure and functioning. Integrating lake size within the conceptual framework of the GEH could aid in explaining mixoplankton success over macroecological scales.

Body-size reductions in dacryoconarid tentaculitoids during Late Devonian warming

Body size is an essential factor in an organism’s survival, and when paired with paleoenvironmental proxies, size trends can provide insights into a lineage’s evolutionary responses to changing environmental conditions. This study explores the diversity and body-volume trends of dacryoconarid tentaculitoids, globally abundant marine zooplankton, in the Devonian of the Appalachian Basin (eastern United States), spanning the late Givetian through the middle Frasnian punctata carbon isotope excursion. Using statistical approaches to model trends, we find evidence of a gradual, within-lineage reduction in styliolinid adult body sizes starting at the Givetian-Frasnian boundary. This reduction is followed by a significant decrease in both adult and initial chamber volumes during the punctata excursion. At the Givetian-Frasnian boundary, annulated forms (nowakiids) become rare and smooth forms (styliolinids) begin to dominate the assemblage. Using pre-existing geological and geochemical data sets, we consider environmental factors, including sea level, anoxia, nutrient availability, and temperature, as potential drivers of body-size reductions. Bottom-water anoxia most likely did not influence body-size trends of this pelagic group, but frequent water-column overturning in the Frasnian or other exchange between deep and shallow water may have affected taxonomic composition, favoring styliolinids. Sea-surface temperature correlates inversely with body size, suggesting that warming beginning in the early Frasnian may have contributed to gradual, long-term size reductions. Rising temperatures through the middle Frasnian may have led to the disappearance of dacryoconarids in the northern Appalachian Basin after the excursion.

Multifunctional fluorescent Pseudomonas: effects on maize development and tools for their selection

Maize is one of the most cultivated cereals worldwide. Despite the low nutrient availability in the soil, high amounts of fertilizers are applied causing economic and environmental impacts. Then, Plant Growth Promoting Rhizobacteria (PGPR) as Fluorescent Pseudomonas can be utilized as an alternative. The present work aims to analyze the effect of Pseudomonas isolates on maize development and production and verify the relationship between growth mechanisms and IAA production. Sixteen Pseudomonas isolates were tested in vitro to produce IAA, ACC deaminase, siderophores, and solubilize Fe and Al phosphates. Three isolates (CBSAL02, CBSAL05, and CBSAL06) were selected for the field experiment, in which an A. brasilense inoculant was the control, generating five treatments with four replications. More than 50% of the isolates demonstrated the tested mechanisms. Only CBSAL05 did not produce siderophore or could fix N. Inoculations with A. brasilense and Pseudomonas isolates increased leaf N content among the selected isolates. The CBSAL06 isolate increased productivity, thus demonstrating the potential use as an inoculant.

Unlocking higher yields in Urochloa brizantha: the role of basalt powder in enhancing soil nutrient availability

This study investigates the effect of basalt powder on soil fertility through changes in its chemical characteristics and the response of Urochloa brizantha to different application doses. The experiment was conducted in a greenhouse using two distinct soil types: Oxisol (OX) and Typic Quartzipsamment (TQ). Basalt powder dosages were determined based on the calcium levels required to adjust calcium contents in each soil (Ca2+) to recommended levels for the U. brizantha,ranging from 0 to 4 times the recommended amount. After 170 days of incubation, soil samples were collected for analysis to evaluate soil attributes. U. brizantha was then planted to assess the efficiency of basalt powder, which was harvested at 40 days after sowing (first cut) and 70 days after sowing (second cut). The accumulation of nutrients and shoot dry mass (SDM) production were subsequently measured. The findings revealed that applying the highest dose of basalt powder (96 Mg ha−1) substantially elevated pH, and increased concentrations of phosphorus (P), potassium (K+), calcium (Ca2+), magnesium (Mg2+), copper (Cu), boron (B), and silicon (Si) in Oxisol (OX), while decreasing aluminum (Al3+) contents in the same soil. Furthermore, an average increase in the SDM of both U. brizantha harvests was observed, with a 6% increase in TQ and a 27% increase in OX. Additionally, an increase in the accumulation of P, K, Ca, Mg, and sulphur (S) in the shoot dry mass of the plants was observed with the basalt powder doses. These findings suggest that basalt powder has the potential to be an environmentally friendly alternative for soil fertilization, with positive impacts on soil chemical attributes and plant growth and nutrition.

Effects of Rotary and Deep Tillage on Soil Environment and Melon Root Development.

Tillage practices significantly influence crop yield and soil quality. This study investigated the impact of rotary tillage (RT) and deep tillage (DT) on soil properties, microbial diversity, and melon (Cucumis melo L.) root growth and yield. RT involved breaking up the topsoil to a depth of 15 cm using a rotary tiller, while DT employed a rotary tiller followed by a moldboard plow to turn the soil layer over to a depth of 35 cm. The melon variety "Nasimi" was used as the material. Our findings revealed a remarkable response of soil phosphorus to tillage practices. High-throughput sequencing results revealed a significant impact of tillage practices on the soil fungal composition, richness, and diversity but little impact on the bacterial communities. Compared to RT, DT markedly enhanced melon root length, root surface area, root volume, and mean root diameter by 47.42%, 56.70%, 58.83%, and 27.28%, respectively. Additionally, DT treatments significantly increased melon yield (53.46%) compared to RT. The results indicate that DT improves soil nutrient availability, affects soil fungal community characteristics, and optimizes root distribution in soil, thereby improving melon yield. The findings offer valuable theoretical insights for the implementation of effective tillage practices in open-field melon cultivation.

Interaction Effects of Nutrient and Water on Crop Production System under Dry and Irrigated Agriculture System

Many areas in India, including dryland areas, are under stress from two main obstacles to agricultural output, namely, inadequate soil nutrients and a scarcity of water. In most rainfed regions, except for a few places that can conduct irrigation, low precipitation levels and their erratic distribution usually result in soil water deficiency which leads to water as well as the instances of nutritional stress. Hence, in sustainable agricultural production systems, soil water and nutrient stress are major concerns. In crop production systems, the interplay between water and nutrients might yield favourable results, contingent on the growth stages, volumes, combinations, and balance of the crops. In irrigated areas, water and nutrients have interdependent effects. Efficient water management can enhance nutrient availability and transformation in soil or fertilizers. Water boosts plant nutrient content, uptake, and overall efficiency. Water scarcity stresses plants, impeding root growth and nutrient absorption. Additionally, it has been discovered that there is typically a strong, nearly linear correlation between crop yield and nutrient and water management techniques. Water availability and nutrient efficiency are therefore intimately related. The water state of the soil should be taken into consideration when applying nutrients in a balanced manner, taking into account their types, ratios, amounts, timing, and methods, in addition to their capacity to give nutrients. Therefore, determining the best time or growth stage to add water and nutrients to various crops, as well as how water and nutrients interact, are essential for a sustainable crop production system.

Control of Cyanobacterial Algal Blooms and Soluble Reactive Phosphorus Using PAK-27 and Phoslock®

Cyanobacterial harmful algal blooms (cHABs) can pose a threat to human health and aquatic ecosystems when they release cyanotoxins in water. This research used samples from two northeastern reservoirs in Ohio and assessed (i) the effectiveness of two PAK-27 dosages, (ii) the potential interference of natural organic matter (NOM) on PAK-27 effectiveness, and (iii) the ability of Phoslock® to adsorb phosphorus released during cell lysis to prevent future bloom formation. PAK-27 was applied in either a quarter (15 mg) or full (58 mg) dose in 1.6 L. Two sets of jars were amended with 200:1 Phoslock®:phosphorus 24 h after PAK-27 application to assess the adsorption of phosphorus released upon cell lysis. A final set of jars was amended with 5 mg NOM to evaluate if NOM would interfere with PAK-27 effectiveness. Quarter and full doses of PAK-27 significantly decreased total phycocyanin content within 2 days of application (p < 0.05). However, the addition of 5 mg NOM influenced nutrient availability and algal response. All jars that received algaecide had increased extracellular microcystin levels (p < 0.05). Although Phoslock® adsorbed soluble reactive phosphorus (SRP), jars treated with only PAK-27 or amended with 5 mg NOM reduced more SRP than Phoslock®.Graphical

Potential nutrient, carbon and fisheries impacts of large-scale seaweed and shellfish aquaculture in Europe evaluated using operational oceanographic model outputs

Large-scale seaweed and shellfish aquaculture are increasingly being considered by policymakers as a source of food, animal feed and bioproducts for Europe. These aquacultures are generally thought to be low impact or even beneficial for marine ecosystems as they are ‘extractive’ – i.e., growing passively on foodstuff already available in seawater, and with potential habitat provision, fisheries, climate mitigation and eutrophication mitigation benefits. At some scale however, over-extraction of nutrients or chlorophyll could potentially have a negative effect on natural systems. Understanding the likely impacts of aquaculture production at scale is important to identify when safe limits are being approached. Taking seaweed aquaculture as the primary focus, this work uses operational oceanographic model outputs to drive prognostic growth models to predict the likely optimal distribution of seaweed farms across European waters to meet different production scenarios. A novel nutrient transport scheme is then used to model the interacting ‘footprints’ of nutrient drawdown from aquaculture facilities to demonstrate the likely spatial impact of large-scale aquaculture. Evaluation of both seaweed and shellfish contributions to CO2 balance under large scale production, and the potential impact on fisheries are also considered. The study finds that the impact of intensive seaweed aquaculture on nutrient availability could be significant where many farms are placed close together; but at the regional/basin scale even the highest level of production considered does not significantly impact total nutrient budgets. Seaweed aquaculture has the potential to extract large amounts of carbon dioxide, but the impact on carbon budgets depends on the end-use of the extracted seaweed. Shellfish aquaculture is a net source of CO2 due to the impact of calcification of shells on the carbonate system (i.e., alkalinity removal). However, gram-for-gram the CO2 impact of shellfish production is likely to be less than the impact of land-based meat production. Whilst operational oceanographic models are useful for taking a ‘broad brush’ approach to likely placement and impacts of aquaculture, reliable yield predictions for individual locations across European waters would require models integrating more physical and biogeochemical factors (wave environment, local currents, riverine inputs) at a finer scale than currently achievable.

Response of Integrated Nutrient Management (INM) Practice on Growth, Yield and Quality Parameters of Fenugreek (Trigonella corniculate L.)

Integrated nutrient management methods assist improve fenugreek (Trigonella corniculate L.) development and yield by integrating the use of organic and inorganic fertilizers. These methods enhance soil fertility, increase nutrient availability, and improve plant health, all of which lead to increased crop yield, growth and quality. Future policies must place a high priority on the economical, sustainable, and efficient use of nutrient resources for the purpose to increase agricultural output. Thus, proper crop, water, soil, and land management along with integrated nutrient management are necessary for sustainable agriculture. Improved soil qualities and increased nutrient availability for agricultural plants come from the use of organic manures in conjunction with inorganic fertilizers. This enhances fenugreek growth, yield, and quality measures. The synthesis of carbohydrates, phytohormones, and even biofertilizers is enhanced by a nutritious diet. It also builds up the soil's organic status, which raises the availability of other nutrients and contributes to the maximum growth of crops. Vermicompost, farmyard manure, rhizobium, phosphorus- and potassium-soluble bacteria (PSB) are among the materials used in methi cultivation that support sustainable agriculture by enhancing soil fertility, nutrient availability, and general crop health, all of which lead to higher methi yields and quality. Organic matter is a storehouse of nutrients; applying both organic and inorganic fertilizer together can boost yields, improve soil fertility, raise crop input-use efficiency, and reduce the need for expensive fertilizers. This crop responds effectively to N provided through a combination of organic and inorganic sources. Majority of the nitrogen applied from different sources is not used by the first crop and is always reflected in the crop that follows. Therefore, it is necessary to assess how integrated nutrition management affected fenugreek's yield and nutrient uptake.

Change in leaf C:N:P stoichiometry and its correlations with soil available nutrients and dry matter yield in common vetch/oat intercropping under N fertilization

AbstractC, N, and P concentrations and stoichiometric ratios of the leaf are important for adaptive plant growth and nutrient utilization. However, our knowledge of how these traits change with N fertilization in intercropping systems remains limited. Hence, a 2‐year experiment was conducted with four cropping patterns, including two‐row common vetch (Vicia sativa L.) intercropping with one‐row oat (Avena sativa L.), one‐row common vetch intercropping with two‐row oat as well as sole oat and common vetch cropping with 0, 50, and 100 kg N/ha fertilization. Leaf total nitrogen (LTN) and phosphorus (LTP) concentrations and C:N:P stoichiometric ratios were measured and their linkages with soil nutrient availability were analysed. N fertilization significantly increased LTN, N:P, and C:P, while significantly decreasing LTP and C:N. Intercropping affected leaf nutrient concentrations and stoichiometric ratios, which were affected by N fertilization, basic soil fertility, and crop species. Intercropping and N fertilization affected soil nitrate nitrogen (SNN), available phosphorus (SAP) content, and dry matter (DM) yield. There were strong correlations between the leaf nutritional traits of oats and SNN, SAP, and DM, but few correlations were observed with common vetch. In conclusion, intercropping led to contrasting changes in leaf nutrient concentrations and stoichiometric ratios, which varied with N fertilization and crop species. We failed to reveal solid and direct effects of intercropping ratio on leaf nutritional traits. These findings contribute to a better understanding of crop nutritional traits and the link between leaves and soil in response to intercropping and N fertilization.

Circadian Regulatory Networks of Glucose Homeostasis and Its Disruption as a Potential Cause of Undernutrition.

The circadian clock system, an evolutionarily conserved mechanism, orchestrates diurnal rhythms in biological activities such as behavior and metabolism, aligning them with the earth's 24-hour light/dark cycle. This synchronization enables organisms to anticipate and adapt to predictable environmental changes, including nutrient availability. However, modern lifestyles characterized by irregular eating and sleeping habits disrupt this synchrony, leading to metabolic disorders such as obesity and metabolic syndrome, evidenced by higher obesity rates among shift workers. Conversely, circadian disturbances are also associated with reduced nutrient absorption and an increased risk of malnutrition in populations such as the critically ill or the elderly. The precise mechanisms of these disturbances in leading to either overnutrition or undernutrition is complex and not yet fully understood. Glucose, a crucial energy source, is closely linked to obesity when consumed excessively and to weight loss when intake is reduced, which suggests that circadian regulation of glucose metabolism is a key factor connecting circadian disturbances with nutritional outcomes. In this review, we describe how the biological clock in various tissues regulates glucose metabolism, with a primary focus on studies utilizing animal models. Additionally, we highlight current clinical evidence supporting the association between circadian disturbance and glucose metabolism, arguing that such disruption could predominantly contribute to undernutrition due to impaired efficient utilization of nutrients.