Search Results (1,163)

Innovation in cultivation methods is essential to address the growing challenges in agriculture, including abiotic and biotic stress, soil degradation, and climate change. Aeroponics, a particular type of hydroponics, presents a promising solution by improving yield and resource use efficiency, especially in controlled environments such as plant factories with artificial lighting (PFALs). Additionally, non-thermal plasma (NTP), a partially ionized gas containing reactive oxygen and nitrogen species, can affect plant development and physiology, further enhancing crop production. The objective of this study was to explore the potential of NTP as an innovative method to enhance crop production by treating the nutrient solution in aeroponic systems. During this study, three experiments were conducted to assess the effects of NTP-treated nutrient solutions on baby leaf lettuce (Lactuca sativa L.) aeroponically grown indoors. The nutrient solution was treated with ionized air in a treatment column separated from the aeroponic system by making the ionized air bubble from the bottom of the column. After 2 min of NTP application, a pump took the nutrient solution from the treatment column and sprayed it on the roots of plants. Various frequencies of NTP application were tested, ranging from 2.5% to 50% of irrigation events with nutrient solution activated with NTP. Results indicated that low-frequency NTP treatments (up to 5% of irrigations) stimulated plant growth, increasing leaf biomass (+18–19%) and enhancing the concentration of flavonoids (+16–18%), phenols (+20–21%), and antioxidant capacity (+29–53%). However, higher NTP frequencies (25% and above) negatively impacted plant growth, reducing fresh and dry weight and root biomass, likely due to excessive oxidative stress. The study demonstrates the potential of NTP as a tool for improving crop quality and yields in aeroponic cultivation, with optimal benefits achieved at lower treatment frequencies. Full article

High boron (B) concentrations in the soil can cause toxic effects to plants, so herbaceous cotton (Gossypium hirsutum latifolium Hucth) is a crop sensitive to such stress. Thus, this study aimed to evaluate the emergence, partitioning, and allocation of metabolic compounds of two herbaceous cotton cultivars subjected to B treatments. The experiment was carried out in a greenhouse, under a completely randomized design in a 2 × 4 factorial scheme, using two cultivars and four concentrations of B in the form of boric acid: 0.5 (control), 30, 60, and 120 mg dm⁻³ B. The increase in the concentration of B in the soil generated a significant toxic effect on the growth and biomass of the cotton plant. Cultivar 1—TMG 50 WS3 obtained greater emergence and shoot growth, while cultivar 2—FM 911 GLTP invested in roots; however, in both cultivars, B remained accumulated in the shoot. There was an increase in amino acids in the roots and a decrease in proteins and phenolic compounds in leaves and cotyledons. It was concluded that the seedlings presented satisfactory emergence up to 60 mg dm⁻³ B, and that among the cultivars there are distinct responses to B application. Full article

The objective of this experiment was to determine whether compound microbial inoculants could enhance the fermentation of oat and common vetch silage that were stored in the Northwest Sichuan Plateau for 60 days under extremely low temperatures. Oat and common vetch harvested from single and mixed artificially planted grassland of oat and common vetch were chopped into 2–3 cm (oat, S1; common vetch, S2; oat–common vetch = 2:1, S3), then sterile water (T1), Zhuang Lemei IV silage additive (T2), and Fu Zhengxing silage additive (T3) were added to the feed and ensiled at the local outdoor environment for 60 days. Data were analyzed as a 3 × 3 factorial arrangement of treatments with the main effects of the materials, additives, and their interaction. Interactions between the materials and additives significantly affected the fermentation quality and the content of DM, WSC, and NDF and the number of yeasts in forages. Treatments with S3 have significantly higher contents of lactic acid, acetic acid, and lactic acid bacteria in the feed than those in the S1 and S2 treatments, while the contents of AN/TN and propionic acid were significantly lower compared with the S1 and S2 treatments (p < 0.05). Concentrations of lactic acid, acetic acid, and propionic acid were significantly increased and the content of neutral detergent fiber in the T2-treated silage decreased compared with the T1 treatment (p < 0.05). The T3 treatment significantly reduced the number of yeasts in the silage but the compound lactic acid bacteria additive treatment (T1, T2) significantly decreased the butyric acid content and pH of the feed and increased the acid detergent fiber content and the number of lactic acid bacteria in the feed compared with the T1 treatment. Among them, the butyric acid content of the T3 treatment decreased by 63.64–86.05%, while that of the T2 treatment decreased by 36.36–83.33% (p < 0.05). The comprehensive analysis of the membership function revealed that the silage quality was the best after the S3T2 treatment, so the implementation of the S3T2 combination in the Northwest Sichuan Plateau can provide guarantees for the production of local high-quality forage grass and alleviate the shortage of forage grass. Full article

This study investigates the formation of cold air pools during calm, anticyclonic winter nights in a topographic basin bounded by a medium-sized mountain to the east and near-flat terrain elsewhere. The main objective is to understand how local topography drives unique topoclimatic conditions—specifically cold air lakes and an inversion layer at approximately 100/120 m altitude—in a peri-urban depression where a major cement factory and several residential areas are located. To achieve this, the research design combined surface measurements (collected at 10:00 p.m., 3:00 a.m., 7:00 a.m., and 3:00 p.m.) using a motorized vehicle, with vertical measurements (at 7:00 a.m.) collected via two unmanned aerial vehicles (UAVs), with the three vehicles equipped with Tinytag data loggers. The Empirical Bayesian Kriging tool in ArcGIS Pro was employed to generate the surface temperature cartograms. The results show that shortly after sunset, a cold air layer of approximately 100–120 m thickness forms, with nocturnal air temperature variations of up to 8 °C on the night measurements. An inversion layer was detected at around 120–130 m, while near-zero wind speeds in the basin’s core facilitate the retention of cold air. Surface spatialization confirms earlier findings of a cold air lake and thermal belts on the basin’s perimeter, forming in the early evening and dissipating by late morning. A 3D visualization underscores the influence of the mountain in directing cold air downslope, leading to stabilization and stratification within the lower atmospheric layers. These findings carry significant health implications: air pollutants released by the cement plant tend to accumulate within the cold air pool and beneath the inversion layer, posing potential risks to nearby populations. Full article

Land use change is associated with both higher fossil fuel usage and global cement production, significantly impacting environmental sustainability. Cement dust emission is the third-largest source of anthropogenic CO₂ emissions, right behind fossil fuel usage due to intense agricultural practices like aggressive tillage management. This study’s aim is to determine cement dust emissions impacts on various tillage management methods and the formation of cement dust-affected CO₂ emissions, soil pH, soil organic matter content, total nitrogen content, available phosphorus, CaCO₃ content, bacteria and fungi populations, and enzyme activities. The target of this study is to evaluate how cement dust emissions impact the soil properties and sustainability of different tillage practices. Composite soils from wheat–sugar beet (potato)–fallow cropping sequences under conventional tillage (CT) and no-till (NT) management were collected (0–30 cm depth) with three replications at varying distances from a cement factory (1, 2, 4, 6, 8, and 10 km). To find differences among individual treatments and distances, a two-way ANOVA was employed along with Duncan’s LSD test comparing the various effects of tillage techniques. The associations between soil chemical and biological properties and CO₂ fluxes under the impact of cement dust were examined using Pearson’s correlation analysis. There were notable relationships between soil microbial population, enzyme activities, pH, CaCO₃, and CO₂ fluxes. The sampling distance from the cement plant had a substantial correlation with soil organic carbon, urease activity, pH, CaCO₃, and bacterial populations. According to the study, different tillage methods (CT and NT) affected the diversity and abundance of microorganisms within the soil ecosystem. CT was more beneficial for the microbial population and for sustainable management. Full article

This study was conducted to assess the antioxidant potential of polyphenolic extracts from Rhizophora mucronata and Avicennia marina as natural preservatives in comparison with synthetic butylated hydroxytoluene (BHT) and rosemary extract. Antioxidant activities were assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC), and total phenolic content (TPC). Extracts were blended into linseed oil and evaluated for oxidative stability using a 15-day Schaal oven test. Physicochemical analyses, including peroxide value (PV), acid index (AI), p-anisidine value (p-AnV), and thiobarbituric acid reactive substances (TBARS), showed that mangrove-treated oils exhibited the highest stability against oxidation compared to the negative and positive controls. R. mucronata mature leaves presented the highest DPPH inhibition (93.40%) and the lowest TBARS value (0.33 ± 0.0 mg MDA/kg of oil) on day 11. Fluorescence spectroscopy provided complementary and valuable information. Statistical analysis using factorial discriminant analysis (FDA) achieved a classification accuracy of 91.43%, underlining the different oxidative profiles of the treated samples. These findings demonstrated the potential of extracts from mangrove plants as a sustainable alternative to synthetic antioxidants for food preservation. Future studies should explore broader food applications using advanced analytical techniques to optimize their efficiency and performing a series of toxicity evaluations. Full article

The biotechnological production of carotenoids offers a promising alternative to their chemical synthesis or extraction from plants. Mycolicibacterium species have shown potential as pigment-producing microorganisms. However, bacterial strains typically exhibit lower productivity compared to fungal and yeast strains. Earlier, we enhanced the β-carotene biosynthesis in M. neoaurum strain VKM Ac-3067D by modifying the cultivation medium. Key changes included replacing glucose with glycerol and soybean meal with skimmed milk powder (SMP) and increasing the urea content from 0.5 to 1.0 g/L. To further optimize β-carotene yield, a steepest ascent method was applied combining factorial design with a gradient-based optimization (Wilson–Box method). The resulting regression model showed that the most influential factors were the glycerol concentration and SPM use. The in-flask fermentation of the Ac-3067D strain in a medium containing 25.5 g/L of glycerol (carbon source) and 12.80 g/L of SMP (nitrogen source) increased β-carotene yield to 318.4 ± 8.3 mg/kg. In a 15 L bioreactor, β-carotene yield increased to 432.3 ± 10.4 mg/kg, while the biomass concentration reached 23.2 ± 1.2 g/L. The further scaling up to a 100 L bioreactor increased both β-carotene yield (450.4 ± 8.2 mg/kg) and biomass concentration (25.2 ± 1.1 g/L). Thus, β-carotene production technology using the M. neoaurum strain AC-3067D was successfully scaled up from 750 mL flasks to a 100 L bioreactor, confirming its potential for industrial-scale application. Full article

Coffee intercropped with Urochloa decumbens modifies nutrient uptake, and consequently the yield and quality of coffee, by the greater release of nutrients and efficient nutrient cycling. There is little information about the increasing nutrient content in Arabica coffee plants intercropped with Urochloa decumbens. The objective of this study was to evaluate the effect of Urochloa decumbens intercropped with two coffee cultivars (Coffea arabica L.) on the levels of macro- and micronutrients and coffee crop yield. The experiment was conducted at Embrapa Cerrados, Planaltina-DF, and was arranged in a completely randomized block design with three replications, in a factorial design. The first factor consists of two management systems: with (WB) and without (NB) Urochloa decumbens intercropped; the second factor is composed of Arabica coffee cultivars ‘IPR-103’ and ‘IPR-99’. There was no significant difference in yield of the coffee cultivars with and without Urochloa decumbens intercropped between the rows. The treatment with ‘IPR-99’ coffee cultivar intercropped with Urochloa decumbens achieved 400 kg ha⁻¹ (8 bags) more than the other treatments. The presence of Urochloa decumbens increased leaf nutrient contents of the macronutrients Ca and Mg and micronutrients Mn and Fe. Thus, the Arabica coffee–Urochloa decumbens intercropping system is an efficiency management strategy which improves nutrient content for the main crop with consequent yield gains. Full article

Light is a key factor influencing the growth and quality of crops in plant factories. To explore the optimal light quality for pakchoi production, five light formulations were applied to ‘Youguan NO.3’ pakchoi: white LEDs (W; CK); white/red = 4:1 (WR); white/blue = 4:1 (WB); white/red/blue = 3:1:1 (WRB); and white/green = 4:1 (WG), all with a light intensity of 250 ± 10 µmol·m⁻²·s⁻¹. The results showed significant variations in growth indices, nutritional quality, enzyme activity, and other parameters under different light qualities. The best growth results were observed under the WRB treatment. Chloroplasts under WRB treatment appeared well-developed, with clear grana lamellae. The thylakoids in the chloroplast grana of the WRB plants were densely stacked, and a large number of starch grains were detected. The contents of total sugar, soluble sugar, soluble protein, and protein nitrogen were significantly higher under the WB, WRB, and WR treatments compared to the CK treatment, along with a significant reduction in nitrate content. Among all the treatments, WRB treatment resulted in the highest levels of total sugar, starch, free amino acids, soluble protein, total nitrogen, protein nitrogen, and ascorbic acid (AsA). Enzyme activity assays revealed that the activities of sucrose phosphate synthetase (SPS), nitrate reductase (NR), glutamine synthetase (GS), glutamate synthetase (GOGAT), and glutamate dehydrogenase (GDH) were highest under WRB treatment. Therefore, supplemental red-blue mixed light can effectively improve the growth and nutritional properties of pakchoi grown under white light. This supplementary lighting strategy provides a new way to enhance the nutritional value of leafy vegetables in plant factories. Full article

Satureja rechingeri is a valuable medicinal plant, but its growth can be significantly impacted by water deficit stress. To investigate the effects of biochar (BC) and hydroretentive polymers (HPs) on various eco-physiological traits of savory under a water deficit, an experiment was conducted over two consecutive cropping seasons (2017–2019). A randomized complete block design with a split-plot factorial arrangement and three replications was used. The treatments consisted of three levels of irrigation (95 ± 5, 75 ± 5, and 55 ± 5% FC), which were applied to the main plots, and combinations of two levels of biochar and two levels of HPs, which were applied to subplots. The results show that a water deficit reduced the relative water content (RWC), chlorophyll content, and dry matter yield of the shoots. Furthermore, the activity of catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), and malondialdehyde (MDA) increased in two-year-old plants. The MDA content significantly decreased by 15.6% in the second year compared to in the first year under a water deficit. The application of HPs caused a decrease of 26.4%, 32.5%, and 27.5% in POD, CAT, and APX enzyme activities, respectively, compared to their control levels. In the biochar treatment, there was a significant reduction in the activity of POD, APX, and CAT in the leaves. Full article

The growing integration of renewable energy sources, particularly photovoltaic (PV) and wind power, presents challenges such as reduced system inertia and increased susceptibility to inter-area oscillations. These issues, coupled with stricter regulatory demands for grid stability, highlight the urgent need for effective damping solutions. This study proposes a novel method for detecting and mitigating inter-area oscillations using a power oscillation damping (POD) controller enhanced by applying a Fast Fourier Transform (FFT). The controller’s parameters are optimized through the Nobel Bat Algorithm (NBA) and fully implemented in DIgSILENT PowerFactory (DSPF). Simulations conducted on the New England IEEE-39 power system model under varying levels of renewable energy penetration demonstrate the model’s capability to dynamically detect, mitigate, and deactivate oscillations once stability is achieved. This work addresses emerging regulations requiring oscillation damping systems and offers a framework for certifying POD controllers for real-world implementation, ensuring their adaptability to diverse energy systems and regulatory contexts. Full article

This study evaluated the effects of various supplemental lighting conditions on the growth and rhizome production of Wasabia japonica, a high-value crop. Its cultivation poses challenges due to specific environmental requirements, including cool temperatures and high humidity. By tailoring light spectra, we aimed to optimize photosynthetic efficiency and biomass accumulation. Seedlings (cv. ST1) were grown in a controlled plant factory (18 ± 2 °C, 90 ± 5% RH) using a Yamazaki tri-leaf nutrient solution (EC 1.5–2.0 dS/m, pH 5.8–6.8). Lighting was designed to convert blue (450 nm) to red (630–680 nm) wavelengths at 70–40% ratios, maintaining a photosynthetic photon flux density (PPFD) of 50 ± 5 μmol·m⁻²·s⁻¹ during a 12 h photoperiod. In the greenhouse, supplemental lighting (40% blue-to-red conversion) was applied for 4 h daily to complement natural light. After 140 days, the optimized 40% blue-to-red conversion lighting significantly improved plant length (34.4 cm), leaf length (15.3 cm), and photosynthetic rates (2.21 μmol·m⁻²·s⁻¹). When tested in the greenhouse, it increased rhizome fresh weight to 75.6 g compared to 30.0 g under natural light. These results indicate that supplemental lighting with specific spectral ratios and controlled intensities can enhance photosynthesis and rhizome production, providing a sustainable approach to wasabi cultivation. Full article

Pearl millet (Pennisetum glaucum (L.) R. BR.) is a C4 plant adapted to semi-arid climates and is one of the primary staple foods in Sub-Saharan Africa, including in Namibia. The decline in yields associated with water scarcity over the years has been a national concern in the country. An experimental field trial was conducted at the Mannheim Crop Research Station, Namibia, during the 2023 and 2024 cropping seasons to investigate the response of two local pearl millet cultivars (Kangara and Okashana 2) to different water regimes (100%, 75%, and 50% crop evapotranspiration [ETc]) according to morpho-physiological and yield parameters. Pearl millet was planted in a split-plot factorial design with four rows per plot under the three water regimes, and the genotypes were planted in subplots. The results revealed that the water regime had a significant effect on plant height, number of leaves, tillers, chlorophyll content, stomatal conductance, leaf temperature, stem thickness, number of productive tillers, panicle diameter, panicle length, dry panicle weight, biomass, grain weight, and 1000-seed weight of the two pearl millet cultivars (p < 0.001). At 50% ETc, the water regime significantly reduced the growth and yield parameters compared with the 75% ETc and 100% ETc water regimes, highlighting the significance of water in plant development and growth. The findings highlighted that both cultivars responded similarly to water stress. Seventy-five percent of ETc is recommended to be applied in pearl millet systems in semi-arid conditions. This research has significant implications for the planning and producing of pearl millet under water-limited environments under changing climatic conditions. Full article

Maize planting configuration remains a critical area for increased understanding and optimization, particularly in the context of advancing yield potential and management technologies. A field experiment was conducted in Tifton, Georgia in 2018 to characterize the grain yield and yield components relative to comprehensive ranges of row spacings and seeding rates and to explore the potential merit of alternative parameterizations of space per plant. Treatments comprised a complete factorial arrangement of four row spacings (38, 51, 76, and 91 cm) and four seeding rates (6.9, 8.4, 9.9, and 11.4 seeds m⁻²). Additional metrics evaluated were an inter-plant distance (IPD) and a measure of squareness (SQ) of space per plant. The narrowest row spacing (38 cm) resulted in greater (p < 0.05) ear density and grain yields (8.74 ears m⁻² and 16.3 Mg ha⁻¹) than 76 and 91 cm rows (means = 7.90 m⁻² and 14.3 Mg ha⁻¹) across seeding rates. Increasing the seeding rate also increased ear density and decreased kernels row⁻¹, but did not affect the yield. Among all parameters assessed, the IPD and SQ were most influential on both ear density and the ultimate grain yield, indicating positive yield associations not only with crowdedness (greater density), but also with maximum squareness (or balance) of space per plant. These findings warrant continued experimentation and careful integration of reduced maize row spacing in high-yield environments. Full article

Panax notoginseng (Burkill) F. H. Chen, as a traditional Chinese medicinal herb with significant therapeutic effects, is highly sensitive to environmental factors during its growth process, particularly light and water conditions. Under traditional field conditions, natural limitations make it difficult to achieve optimal yield and quality. This study aimed in the past to determine the optimal light–water interaction model for the year-round cultivation of P. notoginseng in a controlled plant factory environment. The experiment used one-year-old, uniformly grown P. notoginsen seedlings. At the beginning of the experiment, the light source, without any shading treatment, provided a photosynthetically active radiation (PAR) intensity of 200 μmol·m⁻²·s⁻¹, measured at a distance of 30 cm from the plant canopy. A total of 18 treatment combinations were established, specifically two different light quality treatments (A Treatment with a red-to-blue light ratio of 4:1 and B Treatment with a red-to-blue light ratio of 5:1) were each combined with three irrigation levels (field water capacities of 40%, 50%, and 60%) and three shading levels (one layer of 60% shading net, two layers of 60% shading net, and three layers of 60% shading net). Each light quality treatment was combined with all three irrigation levels and all three shading levels, resulting in 18 distinct treatment combinations. The effects of different light–water interactions on P. notoginseng growth were evaluated by measuring key agronomic traits, chlorophyll fluorescence parameters, and ginsenoside content. The results indicate that light–water interactions significantly affect the agronomic traits, chlorophyll fluorescence parameters, and ginsenoside content of P. notoginseng (light treatment had a more significant impact on the growth of P. notoginsen than water treatment). The best performance in terms of plant height (15.3 cm), stem diameter (3.45 mm), leaf length (8.6 cm), fresh weight (3.382 g), and total ginsenoside content (3.8%) was observed when the red-to-blue light ratio was 4:1 (A Treatment), the field water capacity was 50%, and the shading level was three layers. Based on this, the Pearson correlation analysis was used to identify eight highly correlated indicators, and the entropy-weighted TOPSIS model was applied to comprehensively evaluate the cultivation schemes. The evaluation results show that the optimal cultivation scheme for P. notoginseng is under the conditions of a red-to-blue light ratio of 4:1 (A Treatment), field water capacity of 50%, and three-layer shading. Full article