Efficiency Of Food Utilization Research Articles

Garlic-specific Fertilizer Improves Economic and Environmental Outcomes in China

Traditional methods of garlic fertilization involve large amounts of balanced fertilizer with equal proportions of N, P, and K, leading to nutrient imbalances, reduced yield and nutritional quality, and elevated risk of environmental pollution. This study for the first time measured garlic nutrient absorption and mineral elements status in garlic fields. In addition, a garlic-specific fertilizer formula and recommended rate were designed and applied in multiple garlic fields during the 2019–21 growing season. We assessed the performance of garlic-specific fertilizer in terms of yield, quality, and nutrient utilization efficiency. We showed that garlic prefers to absorb N and K, and its absorption of P was much lower. Deficiencies in Cl, Mn, S, and Fe are found in 98.7%, 56.1%, 22.8%, and 11.9% of garlic fields. Compared with farmer fertilization, the garlic-specific fertilizers increased sprout yield by 12.9% to 30.5%, bulb yield by 11.0% to 33.5%, and net income by 18.2% to 45.6%. Furthermore, it improved the nutritional quality [vitamin C (Vc), soluble sugar (SS), and soluble protein] of the garlic and reduced the accumulation of nitrate. The formula of special fertilizer was more in line with the law of garlic nutrient absorption, increasing the nutrient utilization effect, reducing the environmental risks. Application of specific fertilizer increased N, P, and K partial productivity by 26.6% to 50.1%, 82.6% to 116.5%, and 54.6% to 83.3%, respectively. These results suggest that replacing balanced fertilizers in the garlic market with garlic-specific fertilizers can improve garlic farmers' incomes and soil health.

Research on the function of CsMYB36 based on an effective hair root transformation system

ABSTRACT The hairy root induction system was used to efficiently investigate gene expression and function in plant root. Cucumber is a significant vegetable crop worldwide, with shallow roots, few lateral roots, and weak root systems, resulting in low nutrient absorption and utilization efficiency. Identifying essential genes related to root development and nutrient absorption is an effective way to improve the growth and development of cucumbers. However, genetic mechanisms underlying cucumber root development have not been explored. Here, we report a novel, rapid, effective hairy root transformation system. Compared to the in vitro cotyledon transformation method, this method shortened the time needed to obtain transgenic roots by 13 days. Furthermore, we combined this root transformation method with CRISPR/Cas9 technology and validated our system by exploring the expression and function of CsMYB36, a pivotal gene associated with root development and nutrient uptake. The hairy root transformation system established in this study provides a powerful method for rapidly identifying essential genes related to root development in cucumber and other horticultural crop species. This advancement holds promise for expediting research on root biology and molecular breeding strategies, contributing to the broader understanding and improvements crop growth and development.

Improving Primary Nutrients (NPK) Use Efficiency for the Sustainable Production and Productivity of Cereal Crops: A Compressive Review

Nutrient Use Efficiency (NUE) is the capacity of certain crops to use the available nutrients for growth, development, and productivity. Enhancing the efficiency of nutrient utilization by cereals is an admirable objective and a major problem for the fertilizer sector and agriculture as a whole. Nutrient use efficiency (NUE) is a critical concept in the evaluation of cereal production systems. Therefore, this study aimed to review methods for improving the efficiency of primary nutrient (NPK) use in cereals (Barley, Rice, wheat, Maize, Sorghum, and Sugarcane)  for sustainable production and productivity. Soil, plant water, and fertilizer management can have important impacts on the nutrient-use efficiency of cereals. Nutrient utilization aims to maximize the overall performance of cropping systems by providing the crop with the most inexpensive sustenance possible, while reducing nutrient losses from the field. The NUE takes care of some, but not all, of that performance. Thus, in addition to NUE, total productivity must is one of the aims of system enhancement. The question being posed and, frequently, the spatial or temporal scale of interest for which trustworthy data are available, dictate the most appropriate approach to NUE. For N, P, and K, the partial nutrient balance (the ratio of nutrients removed by crop harvest to fertilizer. Although opinions differ, agronomic nutrient use efficiency is the foundation for both economic and environmental efficiency. Economic and environmental efficiencies arise from increased agricultural efficiency. Therefore, different researchers have investigated ways to improve the nutrient use efficiency of cereals by using mechanisms including optimizing nutrient usage, nano-fertilizer usage, breeding for nutrient use efficiency, and precision farming.

Exploring the potential of enhanced organic formulations for boosting crop productivity, nutrient utilization efficiency, and profitability in baby corn-kabuli gram-vegetable cowpea cropping system

The preparation of enriched formulation by integrating of agricultural wastes such as paddy husk ash (PHA) and potato peel with organic fertilizer such as farmyard manure (FYM), compost can enrich the soil with essential plant nutrients, leading to higher yields in subsequent crops and potentially reducing the dependence on farmyard manure/compost alone. However, there is lack of adequate research findings regarding the impact of different formulations generated from agricultural waste on productivity, nutrient utilization efficiency and profitability of baby corn-kabuli gram-vegetable cowpea cropping system. Therefore, a two-year field experiment (2020–2022) was conducted ICAR-IARI, New Delhi with baby corn-kabuli gram-vegetable cowpea cropping system. Seven nutrient sources were tested in Randomized Block Design and replicate thrice.The results showed that treatment T4 (100% recommended dose of nitrogen (RDN) through PHA based formulation) had significant effect on crop yield grown in rotation, followed by treatment T6 (100% RDN through potato peel compost (PPC) based formulation) and T2 (100% RDN through FYM). The increase in yield was 75.0, 44.3 and 33.1% during first year and 72.6, 45.9 and 31.0% during second year, respectively, over control. Treatment T4 also significantly enhanced system uptake of N, P and K as well as system gross returns and net returns, resulting in 65.6, 84.9, 69.5, 50.7 and 55.2% higher returns during first year and 68.6, 80.5, 73.9, 50.0 and 54.2% higher returns during second year, respectively, over control. Furthermore, treatment T4 significantly improved agronomic nitrogen use efficiency and apparent recovery by 151.6 and 2.0% in baby corn, 74.2 and 1.5% in kabuli gram, 55.7 and 13.9% in veg cowpea over T7, respectively, averaged across two years of study. Based on these results, it is recommended to adopt (T4) 100% RDN through PHA based formulation, and (T6) 100% RDN through PPC based formulation in the area with a shortage of FYM but with the availability of rice husk ash or pototo peels for sustainable utilization of the agricultural wastes and improving the agricultural sustainability.

1H-NMR-Based Plasma Metabolomic Profiling of Crossbred Beef Cattle with Divergent RFI Phenotype

This study focused on exploring the metabolomic profiles of crossbred beef cattle with varying levels of residual feed intake (RFI), a measure of feed efficiency in beef cattle. Sixty-seven crossbred growing beef steers (BW = 277 ± 29.7 kg) were subjected to a high-forage total mixed ration for 64 days to determine their RFI phenotypes. At the end of the 64d feeding trial, beef steers were divided into two groups based on their RFI values: low (or negative)-RFI beef steers (n = 28; RFI = −1.08 ± 0.88 kg/d) and high (or positive)-RFI beef steers (n = 39; RFI = 1.21 ± 0.92 kg/d). Blood samples were collected, and plasma samples were analyzed using Nuclear Magnetic Resonance spectroscopy, resulting in the identification of 50 metabolites. The study found a distinct metabolomic signature associated with RFI status. Eight metabolites, including amino acids (tyrosine, glycine, valine, leucine, and methionine) and other compounds (dimethyl sulfone, 3-hydroxy isovaleric acid, citric acid, creatine, and L-carnitine), showed differential abundance between low- and high-RFI groups. Specifically, tyrosine, glycine, and dimethyl sulfone exhibited significant specificity and sensitivity, which produced a discriminatory model with an area under the receiver operating characteristic (ROC) curve of 0.7, making them potential markers for RFI. A logistic regression model incorporating these biomarkers effectively distinguished between high- and low-RFI steers, with a threshold cutoff point of 0.48, highlighting a distinctive metabolite profile associated with efficient nutrient utilization in low-RFI cattle. The logistic regression model, incorporating these biomarkers, holds promise for accurately categorizing RFI values, providing insights into the metabolic basis of feed efficiency in beef cattle.

Patterns and drivers of plant carbon, nitrogen, and phosphorus stoichiometry in a novel riparian ecosystem.

Carbon (C), nitrogen (N), and phosphorus (P) stoichiometry serve as valuable indices for plant nutrient utilization and biogeochemical cycling within ecosystems. However, the allocation of these nutrients among different plant organs and the underlying drivers in dynamic riparian ecosystems remain inadequately understood. In this study, we gathered plant samples from diverse life forms (annuals and perennials) and organs (leaves, stems, and roots) in the riparian zone of the Three Gorges Reservoir Region (TGRR) in China-a novel ecosystem subject to winter flooding. We used random forest analysis and structural equation modeling to find out how flooding, life forms, plant communities, and soil variables affect organs C, N, and P levels. Results showed that the mean concentrations of plant C, N, and P in the riparian zone of the TGRR were 386.65, 19.31, and 5.27 mg/g for leaves respectively, 404.02, 11.23, and 4.81 mg/g for stems respectively, and 388.22, 9.32, and 3.27 mg/g for roots respectively. The C:N, C:P and N:P ratios were 16.15, 191.7 and 5.56 for leaves respectively; 26.98, 273.72 and 4.6 for stems respectively; and 16.63, 223.06 and 4.77 for roots respectively. Riparian plants exhibited nitrogen limitation, with weak carbon sequestration, low nutrient utilization efficiency, and a high capacity for nutrient uptake. Plant C:N:P stoichiometry was significantly different across life forms and organs, with higher N and P concentrations in leaves than stems and roots, and higher in annuals than perennials. While flooding stress triggered distinct responses in the C, N, and P concentrations among annual and perennial plants, they maintained similar stoichiometric ratios along flooding gradients. Furthermore, our investigation identified soil properties and life forms as more influential factors than plant communities in shaping variations in C:N:P stoichiometry in organs. Flooding indirectly impacts plant C:N:P stoichiometry primarily through alterations in plant community composition and soil factors. This study underscores the potential for hydrologic changes to influence plant community composition and soil nutrient dynamics, and further alter plant ecological strategies and biogeochemical cycling in riparian ecosystems.

Paecilomyces variotii (PEKILO®) in novel feeds for Atlantic salmon: Effects on pellet quality, growth performance, gut health, and nutrient digestibility and utilization

Filamentous fungi have potential as an alternative protein source for use in aquafeeds due to their high protein content and bioactive components. Paecilomyces variotii (PEKILO® mycoprotein) is a β-glucan- and nucleotide-rich filamentous fungi with a crude protein (CP) content of 60–70%. A 9-week feeding trial was conducted to evaluate the effects of P. variotii in diets for Atlantic salmon (initial average body weight of 24 g fish−1) reared in freshwater. Four experimental diets were formulated. Diet 1 was a control diet based on fish meal, soy protein concentrate, and wheat gluten meal. Diets 2, 3, and 4 were formulated so that P. variotii replaced 5, 10, and 20% of the CP content of the diets, respectively. Results showed that dietary inclusion of P. variotii was associated with changes in physical pellet quality, including significant linear (p < 0.0001) and/or quadratic (p < 0.01) decreases in pellet length, width, expansion, and durability. Conversely, significant linear (p < 0.0001) and quadratic (p < 0.025) increases in water activity, bulk density, and water stability index were associated with increasing replacement of the CP content of the diets with P. variotii. There were no significant differences in weight gain, growth rate or feed intake among fish fed the experimental diets (p > 0.05), but a significant linear improvement (p < 0.025) in feed conversion ratio (FCR) with increasing dietary inclusion of P. variotii was observed. The apparent digestibility coefficients for CP and gross energy of the experimental diets decreased linearly (p < 0.01) with increasing dietary levels of P. variotii. Similar results were observed for the essential and non-essential amino acids. Despite reduced digestibility, linear increases in nitrogen (p < 0.01), energy (p < 0.025), and mineral (p < 0.001) retention efficiencies were associated with increasing dietary levels of P. variotii. In the distal intestine, dietary inclusion of P. variotii resulted in significant (p < 0.05) upregulation of several cytokines (ifng, il10, and tgfb), effector molecules (inos, arg1, sod), and transcription factors (irf4), suggesting both activation and control of the inflammatory response in this key mucosa-associated lymphoid tissue. Overall, replacement of 20% of the CP content of the diet with P. variotii reduced digestibility of the experimental diets, but did not affect growth performance and improved FCR and nutrient utilization efficiency of salmon. Thus, P. variotii is a promising ingredient with potential for use in salmonid aquafeeds to improve fish performance and health.

Effect of four host plants on the life history and nutritional indices of Spodoptera Littoralis

AbstractThe Egyptian cotton leafworm Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae) is a pervasive and highly polyphagous insect pest. As S. littoralis has developed resistance to major classes of conventional insecticides and the use of these insecticides has caused negative impacts on the ecosystems, it is necessary to search for eco-friendly, cost-effective, and sustainable agents to control. This can be achieved by identifying the preferred host plant. The present study aimed at evaluating the impacts of four host plants– castor bean, tomato, potato, and cucumber on the various life-history traits and nutritional indices of S. littoralis. The concentrations of nitrogen, potassium, and phosphorous in the tested host plants were quantified. Newly hatched larvae were divided into four groups. Each group was fed only on one type of the four tested host plants until pre-pupal stage. Then, the life-history traits and nutritional indices were determined. Larvae fed on castor bean showed the highest adult emergence, weight of full-grown larvae, number of eggs per female, and egg-hatch percent, food consumption, relative growth rate, and food utilization efficiencies. Whereas, larvae fed on cucumber showed the lowest egg-hatch percent, food consumption, relative growth rate, and food utilization efficiencies. There was a positive correlation between nitrogen and phosphorous concentrations in the tested host plants and larval weight, with the highest concentrations in castor bean. Castor bean was the most preferred host plant.

Nanotechnology in plant nutrition: Ensuring sustainable agriculture through nanofertilizers

AbstractFertilizers play a crucial role in enhancing the productivity of plants. However, low nutrient use efficiencies of conventional fertilizers (CFs) associated with several losses have led to widespread multi‐nutrient deficiencies in the soil and lower productivity. Furthermore, their excess application has caused serious damage to the soil and environment. Recently, nanotechnology has broadened its applicability in plant nutrition and has paved a way for the production of nanoparticle‐induced fertilizers. Therefore, nanofertilizers stand out as promising alternative to CFs for sustainable agriculture. Nanofertilizers are composed of nanoparticles that contain macro‐ and micronutrients and deliver them in a controlled way to the plant's rhizosphere. This contributes to the enhanced nutrient utilization efficiency. This review delves into the effect of nanotechnology‐based nanofertilizers in different forms and dosages on soil properties and plant development. Additionally, the mechanism underlying absorption of nanofertilizers and their advantages and limitations have also been discussed. A thorough comparison between conventional and nanofertilizers has also been made in this review in terms of their nutrient delivery mechanism, efficiency and application. As the use of nanoparticle‐embedded fertilizers in plant nutrition is still in its infancy, this review can serve as a guide for future investigations to enhance the knowledge of the use of nanoparticles in the mineral nutrition of different crops.

Temporal Synchronization of Nitrogen and Sulfur Fertilization: Impacts on Nutrient Uptake, Use Efficiency, Productivity, and Relationships with Other Micronutrients in Soybean

Nitrogen (N) and sulfur (S) are essential nutrient elements, and their deficiency affects crop growth, productivity, and nutrient uptake due to their multifaceted role in plant metabolism, which has been well documented. Therefore, agricultural management strategies that can overcome these deficiencies are the need of the hour. In this context, a study was undertaken with the objective to assess the impacts of N and S applications, either basally or through split application (12.5, 25 and 50 kg ha−1), on the nutrient uptake, productivity, use efficiency, and micronutrient content status in soybean seeds, and also the change in soil nutrient zinc (Zn) and iron (Fe) content at different critical stages of soybean crop growth. The field trial was conducted utilizing a randomized complete-block design, and comprised fourteen treatments with varying N and S quantities. N and S were applied through basal and split applications in different combinations. The salient findings indicated that the highest seed, straw yield, N, and S uptake were obtained with the application of N25+25, S25+25, and did not significantly vary with N25+25, S12.5+12.5, N50, and N25+S50. The highest N use efficiency was recorded with the application of N25+S50, and S use efficiency with the application of N25+25, S25+25. The split application of N and S as N25+25, S25+25 significantly increased soil Zn and Fe content at R2 and R5 stages of soybean crop growth, as well as seed Zn and Fe uptake. It can be concluded that the basal and split application of N and S at the rate of 25 kg ha−1 can improve soybean productivity through increased mobilization and assimilation by plants. The findings indicated that applying N and S separately, with 25 kg ha−1 each basally and at the R2 stage resulted in the highest nutrient uptake, and seed and straw yields. The nutrient use efficiencies, along with Zn and Fe uptake by seeds, exhibited noticeable improvements with this split application approach compared to the control. Furthermore, the soil Zn and Fe contents also experienced enhancements due to the split application of both Nand S fertilizers. These results underscore the potential benefits of temporally adopting optimized fertilizer application strategies to maximize agricultural productivity while ensuring efficient nutrient utilization and soil health maintenance. Further research and field trials could provide deeper insights into the long-term impacts and scalability of this approach across different crop varieties and environmental conditions.

Ageing and mating status affect food utilization efficiencies and assimilation of macronutrients in adults of Parthenium beetle, Zygogramma bicolorata Pallister

AbstractInvestigations of age‐based food conversion and utilization efficiencies in phytophagous insects are very few. Studies examining the effects of age, sex and mating status on biochemical assimilation of macronutrients by phytophagous insects are scarce as well. Hence, we designed the present study to evaluate the combined effect of age, sex and mating status on food consumption and utilization efficiencies, and the assimilation of macronutrients by the Parthenium beetle, Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae), on the invasive weed, Parthenium hysterophorus Linnaeus (Asterales: Asteraceae). We hypothesized that mated adults would consume and utilize more food than unmated adults, that assimilation of nutrients by old adults would be lower than young adults and that females would consume and utilize food more efficiently than males. However, our results revealed that as adults aged, their food consumption and utilization efficiencies decreased, and they assimilated less proteins and glucose in their body. Despite that, their mean body biomass and assimilation of triglycerides increased. While mated adults had higher food utilization efficiencies and increased assimilation of triglycerides and glucose, unmated adults assimilated more proteins. Females had higher food consumption rates and increased assimilation of nutrients, whereas males had higher food conversion efficiencies and growth rates. Furthermore, middle‐aged adults had higher food utilization efficiencies and they assimilated more nutrients than young and old adults. Our results therefore suggest compensatory feeding in adults of Z. bicolorata with ageing. We also recommend the release of more numbers of mated middle‐aged females to control P. hysterophorus in agro‐ecosystems.

Evaluating the Varied Impacts of Conventional Versus Nano Fertilizers on Soil Nutrient Levels, Utilization Efficiency and Biological Activity in Acidic Soil

A two-season field experiment was conducted at zonal agricultural research station, GKVK, Bengaluru during Kharif season in 2021 and 2022 with test a crop sunflower. The soil was sandy loam (Alfisol) in texture and experiment was laid out in RCBD with 3 replications and comprised of 14 treatments. Results revealed that the available soil nutrients like nitrogen (307.25 kg ha-1), sulphur (13.28 mg kg-1) and zinc (1.23 mg kg-1) content differed significantly, with treatment T2 (Package of practice). However, all other major, secondary and micro nutrients did not vary significantly. Nutrients use efficiency of nitrogen (72.01 kg kg-1), phosphorus (26.47 kg kg-1) and potassium (35.29 kg kg-1) were recorded higher with nano fertilizers than conventional one. Urease activity (22.42 µg NH4-N g-1 hr-1) was found to be significantly higher in treatment T2 (Package of practice) and enzyme activity like dehydrogenase activity and acid phosphatase activity not significantly varied, the numerical difference was regulated by pH of soil. Combination of conventional and nano fertilizers can be effectively utilized in enhancing the nutrients use efficiency while sustainably managing the soil properties.

Water-Retaining Agent as a Sustainable Agricultural Technique to Enhance Mango (Mangifera indica L.) Productivity in Tropical Soils

Reducing fertilizer doses under sustainable agricultural management is possible by increasing nutrient utilization efficiency, which will decrease crop production costs and boost economic return. Soil amendments known as water retention agents (WRAs) are added to the soil to enhance crop growth conditions. We hypothesize that the addition of WRAs may support the soil-retaining nutrients given through fertilization and prevent them from leaching into tropical soils characterized by severe rainfall due to WRAs’ exceptional capacities to absorb and store water. Mango trees (Mangifera indica L. cv Tainong No. 1) aged 18 years were fertilized with 100% or 80% of the recommended doses of nitrogen (N), phosphorus (P), and potassium (K). The experimental design included three treatments, i.e., complete recommended doses of N, P, and K (CRF), 80% of the complete recommended doses (RRF), and water-retaining agent (40 kg ha−1) + 80% of the complete recommended doses (WRARRF). Reducing the fertilization doses by 20% for mango trees in the studied tropical soil significantly (p &lt; 0.05) minimized the nutrient availability in the soil compared to the complete fertilization doses. WRARRF compensated for the nutrient reduction by increasing the availability of N, P, and K. The addition of WRARR increased N, P, and K in mango leaf by 11%, 4%, and 7% in the first year and by 11%, 6%, and 7% in the second year, respectively, compared to CRF. The addition of WRARR increased the partial fertilizer productivity (PFP) value by 36% and 41% in the first and second years, respectively. The highest mango fruit output was achieved by the addition of WRARRF, which resulted in increases in mango fruit yield of 11.9% and 16.5% in the first and second years, respectively, compared to RRF. Fruit quality traits showed the descending order: WRARRF &gt; RRF &gt; CRF. WRARRF produced the maximum economic benefit (USD 7372 per hectare) compared to CRF and RRF. The polyacrylamide/attapulgite water-retaining agent exhibited remarkable improvement in mango fruit yield and economic profit by regulating the release of nutrients in tropical soils. Water-retaining agents are an effective strategy for overcoming the extensive fertilization used in mango orchards, which has resulted in numerous environmental contaminations and the inefficient use of fertilizers.

Analyses of plasma metabolites using a high performance four-channel CIL LC-MS method and identification of metabolites associated with enteric methane emissions in beef cattle.

Reducing enteric methane (one greenhouse gas) emissions from beef cattle not only can be beneficial in reducing global warming, but also improve efficiency of nutrient utilization in the production system. However, direct measurement of enteric methane emissions on individual cattle is difficult and expensive. The objective of this study was to detect plasma metabolites that are associated with enteric methane emissions in beef cattle. Average enteric methane emissions (CH4) per day (AVG_DAILYCH4) for each individual cattle were measured using the GreenFeed emission monitoring (GEM) unit system, and beef cattle with divergent AVG_DAILYCH4 from Angus (n = 10 for the low CH4 group and 9 for the high CH4 group), Charolais (n = 10 for low and 10 for = high), and Kinsella Composite (n = 10 for low and 10 for high) populations were used for plasma metabolite quantification and metabolite-CH4 association analyses. Blood samples of these cattle were collected near the end of the GEM system tests and a high performance four-channel chemical isotope labeling (CIL) liquid chromatography (LC) mass spectrometer (MS) method was applied to identify and quantify concentrations of metabolites. The four-channel CIL LC-MS method detected 4235 metabolites, of which 1105 were found to be significantly associated with AVG_DAILYCH4 by a t-test, while 1305 were significantly associated with AVG_DAILYCH4 by a regression analysis at p<0.05. Both the results of the t-test and regression analysis revealed that metabolites that were associated with enteric methane emissions in beef cattle were largely breed-specific whereas 4.29% to 6.39% CH4 associated metabolites were common across the three breed populations and 11.07% to 19.08% were common between two breed populations. Pathway analyses of the CH4 associated metabolites identified top enriched molecular processes for each breed population, including arginine and proline metabolism, arginine biosynthesis, butanoate metabolism, and glutathione metabolism for Angus; beta-alanine metabolism, pyruvate metabolism, glycolysis / gluconeogenesis, and citrate cycle (TCA cycle) for Charolais; phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, arginine biosynthesis, and arginine and proline metabolism for Kinsella Composite. The detected CH4 associated metabolites and enriched molecular processes will help understand biological mechanisms of enteric methane emissions in beef cattle. The detected CH4 associated plasma metabolites will also provide valuable resources to further characterize the metabolites and verify their utility as biomarkers for selection of cattle with reduced methane emissions.

Enhancing maize resilience to drought stress: the synergistic impact of deashed biochar and carboxymethyl cellulose amendment

Drought stress poses a significant challenge to maize production, leading to substantial harm to crop growth and yield due to the induction of oxidative stress. Deashed biochar (DAB) in combination with carboxymethyl cellulose (CMC) presents an effective approach for addressing this problem. DAB improves soil structure by increasing porosity and water retention and enhancing plant nutrient utilization efficiency. The CMC provides advantages to plants by enhancing soil water retention, improving soil structure, and increasing moisture availability to the plant roots. The present study was conducted to investigate the effects of DAB and CMC amendments on maize under field capacity (70 FC) and drought stress. Six different treatments were implemented in this study, namely 0 DAB + 0CMC, 25 CMC, 0.5 DAB, 0.5 DAB + 25 CMC, 1 DAB, and 1 DAB + 25 CMC, each with six replications, and they were arranged according to a completely randomized design. Results showed that 1 DAB + 25 CMC caused significant enhancement in maize shoot fresh weight (24.53%), shoot dry weight (38.47%), shoot length (32.23%), root fresh weight (19.03%), root dry weight (87.50%) and root length (69.80%) over control under drought stress. A substantial increase in maize chlorophyll a (40.26%), chlorophyll b (26.92%), total chlorophyll (30.56%), photosynthetic rate (21.35%), transpiration rate (32.61%), and stomatal conductance (91.57%) under drought stress showed the efficiency of 1 DAB + 25 CMC treatment compared to the control. The enhancement in N, P, and K concentrations in both the root and shoot validated the effectiveness of the performance of the 1 DAB + 25 CMC treatment when compared to the control group under drought stress. In conclusion, it is recommended that the application of 1 DAB + 25 CMC serves as a beneficial amendment for alleviating drought stress in maize.

Dynamics of plant nutrient signaling through compost

Nutrient signaling is a fundamental aspect of plant growth and development, encompassing intricate pathways that govern nutrient uptake, allocation, and utilization. Plant growth hormones, root exudates, soil microbes intricately coordinate these processes, responding to nutrient availability and environmental cues. These hormones regulate the expression of transporters, enzymes, and ion channels involved in nutrient acquisition and distribution. Furthermore, plant nutrient signaling pathways interface with hormonal pathways, forming a dynamic regulatory network that allows plants to adapt to changing nutrient conditions and stressors. Additionally, these pathways impact secondary metabolism, root architecture, and nutrient homeostasis, influencing crop yield and quality. Complementing nutrient signaling, through compost application enriches soils, enhancing nutrient availability and soil microbial communities, ultimately optimizing nutrient mobilization and uptake. Understanding these mechanisms is vital for sustainable agriculture and improved crop management, promising increased plant growth, yield, and nutrient utilization efficiency.

Examining the effects of elevated CO2 on the growth kinetics of two microalgae, Skeletonema dohrnii (Bacillariophyceae) and Heterosigma akashiwo (Raphidophyceae)

Carbon dioxide (CO2) serves as the primary substrate for the photosynthesis of phytoplankton, forming the foundation of marine food webs and mediating the biogeochemical cycling of C and N. We studied the effects of CO2 variation on the Michaelis-Menten equations and elemental composition of Skeletonema dohrnii and Heterosigma akashiwo. CO2 functional response curves were conducted from 100 to 2000 ppm. The growth of both phytoplankton was significantly affected by CO2, but in different trends. The growth rate of S. dohrnii increased as CO2 levels rose up to 400 ppm before reaching saturation. In contrast to S. dohrnii, the growth rate of H. akashiwo increased with CO2 increasing up to 1000 ppm, and then CO2 saturated. In addition, H. akashiwo showed a slower growth rate than S. dohrnii for all CO2 concentrations, aside from 1000 ppm, and the Michaelis-Menten equations revealed that the half-saturation constant of H. akashiwo was higher than S. dohrnii. An increase in CO2 concentration was seen to significantly affected the POC: Chl-a of both S. dohrnii and H. akashiwo, however, the effects on their elemental composition were minimal. Overall, our findings indicate that H. akashiwo had a more positive reaction to elevated CO2 than S. dohrnii, and with higher nutrient utilization efficiency, while S. dohrnii exhibited higher carbon fixation efficiency, which is in line with their respective carbon concentrating mechanisms. Consequently, elevated CO2, either alone or in combination with other limiting factors, may significantly alter the relative relationships between these two harmful algal blooms (HAB) species over the next century.

A Response Surface Methodology Study for Chlorella vulgaris Mixotrophic Culture Optimization.

Glycerol is a carbon source that produces good biomass under mixotrophic conditions. Enhancing the composition of culture media in algae biomass production improves growth rates, biomass yield, nutrient utilization efficiency, and overall cost-effectiveness. Among the key nutrients in the medium, nitrogen plays a pivotal role. Urea can be effectively used as a nitrogen source and is considered a low-cost form of nitrogen compared to other sources. Urea metabolism releases some CO2 in photosynthesis, and magnesium plays a major role in urea uptake. Magnesium is another key nutrient that is key in photosynthesis and other metabolic reactions. To maximize glycerol consumption in the mixotrophic system and to obtain high biomass and lipid productions, the variations in MgSO4·7H2O and urea concentrations were evaluated in the growth medium of the microalgae. A response surface methodology (RSM) using a central composite design (CCD) was designed to maximize glycerol consumption at the initial cellular growth rates (up to four days). The magnesium and urea supply varied from 0.3 to 1.7 g L-1. Response surface methodology was utilized to analyze the results, and the highest glycerol consumption rate, 770.2 mg L-1 d-1, was observed when C. vulgaris was grown at 1.7 g L-1 urea, 1.0 g L-1 MgSO4·7H2O. Using the optimal urea and magnesium concentrations with acetate, glucose, and glycerol as carbon sources, the same lipid content (10% average) was achieved on day 4 of mixotrophic C. vulgaris culture. Overall, the results show that mixotrophic growth of C. vulgaris using urea with an optimum magnesium concentration yields large amounts of fatty acids and that the carbon source greatly influences the profile of the fatty acids.

Carbon nanotube reinforced nanohybrid urea-hydroxyapatite fertilizer for an improved nutrients utilization efficiency and reducing environmental pollution

An upgraded technology is needed in the agricultural sector in order to adopt sustainable practice to maintain high yield as well as reducing environmental pollution due to ammonia emissions attributed to mineral nitrogen fertilization. This study reports a modified urea-hydroxyapatite nanohybrids fertilizers incorporated with carbon nanotube for more efficient sustainable nutrients utilization and reduction of ammonia emissions from fertilizers application. The urea-hydroxyapatite fertilizer was mixed with carbon nanotube at varying ratio by mass percentage (Sample A = 1:0.5. B = 1:1, C = 1:2, and D = 1:3) using simple liquid immersion method. The assessment of all the samples and the control specimen (sample E) was conducted by subjecting them to the analysis of thermogravimetric at intervals of 20 min to 200 min, to determine their nitrogen release behaviour activities. The morphological properties of urea-hydroxyapatite fertilizer with and without carbon nanotubes were compared using spectroscopic analysis (SEM, FTIR and XRD). The mechanical tests were conducted to examine the tensile and compressive strengths of the urea-hydroxyapatite fertilizer with carbon nanotubes using diametral tensile strength technique. The data obtained reveals that the control sample (urea-hydroxyapatite fertilizer) released 70 to 80 % urea within first 50minutes while the samples with carbon nanotubes retained urea for longer and 76 to 90 % amount of nitrogen release was recorded in the first 150minutes. It is revealed that the sample C with mixing ratio 1:2 exhibited best slow-release nitrogen properties. The sample C displayed a moderately large amount of nitrogen in form of urea in the initial phase and followed by slow-release even until the last minutes (200minutes). In the contrary, urea-hydroxyapatite fertilizer (control sample) which released heavily in the initial phase followed by the release of low and non-uniform quantities until its last drop towards 150minutes. SEM result demonstrated that chemical reaction occurred between urea-hydroxyapatites particles and carbon nanotubes. XRD patterns of urea-hydroxyapatites nanohybrid structures with carbon nanotubes demonstrate that the samples show the hydroxyapatite properties with monocrystalline structure. It is confirmed from the FTIR spectra that chemical functionalization cropped up between urea-hydroxyapatites nanohybrid and carbon nanotubes particles. A remarkable increase in the mechanical strength (150 % for the tensile strength and 100 % for the compressive strength) of the sample C structures confirms that introduction of carbon nanotubes improved its strength properties for the purpose of prolong stability while discharging its role as a nutrients slow-release fertilizer. Thus, the designed nano-fertilizer formulation of sample C mixing ratio can therefore be used as alternative way of improving the nutrients usage efficiency for the plants growth as well as to reduce the ammonia emission to the environment as pollutant.

Slow-release hydroxyapatite fertilizer from crab shells waste for sustainable crop production

Slow-release fertilizer (SRF) is an alternative to more efficient fertilization. SRF can gradually release nutrients in fertilizer, hence the nutrients needed by for the plant growth will be available for a more extended period. In this study, SRF was made by mixing single fertilizer (urea and ammonium sulfate) with hydroxyapatite particles from crab shell biowaste. Slow-release hydroxyapatite fertilizer synthesized with a ratio between single fertilizer and hydroxyapatite powder of 6:1, then applied to grow Capsicum annuum pepper plants. The result showed that applying hybrid fertilizer affected the growth and yield of Capsicum annuum pepper plant, by enhancement of plant height up to 150 %, stem diameter up to 168 %, number of leaves up to 167 %, number of fruits up to 449 %, fruit diameter up to 200 % and fruit weight up to 234 %, compared with unfertilized plant. The SRF fertilization slightly affect the soil acidity, however the pH changed showed no effect to the plant growth. The use of HA as fertilizer promotes more sustainable crop production, by efficient nutrient uptake and utilization calcium-rich biowaste.