Search Results (209)

Advances in sensor technology have significantly improved the efficiency and precision of agricultural spraying. Unmanned aerial vehicles (UAVs) are widely utilized for applying plant protection products (PPPs) and fertilizers, offering enhanced spatial control and operational flexibility. This study evaluated the performance of an autonomous UAV-based precision spraying system that applies variable rates based on zone levels defined in a prescription map. The system integrates real-time kinematic global navigation satellite system positioning with a proximity-triggered spray algorithm. Field experiments on a rice field were conducted to assess spray accuracy and fertilization efficacy with liquid fertilizer. Spray deposition patterns on water-sensitive paper showed that the graded strategy distinguished among zone levels, with the highest deposition in high-spray zones, moderate in medium zones, and minimal in no-spray zones. However, entry and exit deviations—used to measure system response delays—averaged 0.878 m and 0.955 m, respectively, indicating slight lags in spray activation and deactivation. Fertilization results showed that higher application levels significantly increased the grain-filling rate and thousand-grain weight (both p < 0.001), but had no significant effect on panicle number or grain count per panicle (p > 0.05). This suggests that increased fertilization primarily enhances grain development rather than overall plant structure. Overall, the system shows strong potential to optimize inputs and yields, though UAV path tracking errors and system response delays require further refinement to enhance spray uniformity and accuracy under real-world applications. Full article

Chickpea (Cicer arietinum L.) is a key legume crop of global economic and nutritional importance, yet its cultivation in Kazakhstan is constrained by a narrow genetic base and exposure to stress-prone environments. To characterize the diversity available for breeding and conservation, 27 accessions (22 kabuli and 5 desi) were evaluated for phenotypic and molecular diversity to assess its potential for use in breeding programs. Seven agronomic traits were assessed, including plant height, the first pod’s height, the number of main stems per plant, and seed yield components. The collection showed considerable variability across traits, with the plant height ranging from 37 to 75 cm and hundred-seed weight ranging from 21 to 42 g. Strong positive correlations between the number of fertile nodes, number of seeds per plant, and yield per plant (r > 0.83) highlighted their utility as indirect selection criteria. Genotyping with 28 SSR markers revealed 110 alleles (mean 3.9 ± 0.4 per locus) with moderate polymorphism (PIC = 0.493 ± 0.089). Loci CaM00495 and TAI71 were highly informative (PIC > 0.804), while two accessions showed low polymorphism, indicating genetic uniformity. Population structure analysis grouped accessions into four highly admixed clusters. Overall, Kazakh chickpea germplasm exhibits substantial phenotypic and genetic diversity under optimal conditions, providing valuable preliminary data for selecting parental lines for future breeding programs, which should include targeted stress screening to evaluate resilience. Full article

Given the demand for sustainable and cost-effective manure management in livestock systems, this study evaluated the economic feasibility of cattle manure treatment via composting and anaerobic digestion (AD) under different configurations. Five scenarios were compared: composting without solid–liquid separation, AD without separation at 20- and 30-day hydraulic retention times (HRTs), and combined systems with separation, composting the solid fraction and digesting the liquid. The analysis was based on a 200-cow herd and experimental data, with 15-year projected cash flows. Economic indicators included net present value (NPV), internal rate of return (IRR), discounted payback period (DPP), benefit–cost ratio (B/C), modified internal rate of return (MIRR), uniform annual equivalent (UAE), and profitability index (PI), supported by sensitivity analysis and Monte Carlo simulation. All scenarios were viable and posed low risk. Energy and fertilizer value were key drivers. The scenario 30-day HRT without separation had the best financial performance (NPV = 53,407.15 USD; IRR = 15.54%; DPP = 7.33 years; B/C = 1.57; MIRR = 9.28%; UAE = 5654.48 USD; PI = 1.66) and is recommended for capitalized farms seeking higher returns. Composting had lower returns (NPV = 9832.06 USD) but required the lowest investment, remaining a cost-effective alternative for smallholders. Full article

To enhance the stability and consistency of topdressing depth during maize fertilization, an inter-row deep fertilizer application unit was designed. Through analysis of the coherence between subsurface pressure and topdressing depth stability obtained from stability performance tests, structural optimizations were implemented on the deep application unit. This resulted in an integrated vibration damping device incorporating a magnetorheological damper (MR damper fertilizer application unit). The MR damper fertilizer application unit was validated through simulation testing. Using an orthogonal experimental design approach, soil bin tests were conducted to identify the preferred parameter ensemble for this unit. Subsequent field trials under these optimized parameters enabled comparative performance evaluation of both fertilizer application units under actual operating conditions. The simulation results indicated that the MR damper fertilizer application unit achieved reductions in the standard deviation of the gauge wheel’s force on the ground by 39.6%, 41.0%, and 44.6% at three distinct operational speeds, respectively. The soil bin tests identified the optimal operational parameters as follows: MR damper current of 0.6 A, vibration damping system spring stiffness of 8 N/mm, and a working speed of 7.2 km/h. Field testing results indicated that, when utilizing the optimal parameters, the MR damper fertilizer application unit achieved a 6.9% improvement in the rate of qualified topdressing depth and a 3.8% reduction in the depth variation coefficient compared to the conventional deep fertilizer application unit. Compared to traditional fertilizer applicators, this study effectively addresses issues of poor fertilization depth uniformity and low qualification rates caused by severe gauge wheel bouncing due to uneven terrain during field operations. Full article

Cotton is one of the most important crops worldwide, having considerable economic importance in Greece. This study aimed to evaluate the fiber quality traits of partially interspecific cotton lines under contrasting irrigation and nitrogen environments within a strip-split block field design. Experiments conducted over two consecutive years include a control (commercial cultivar Celia) and four partially interspecific lines of the Pa7 generation (Gossypium hirsutum × G. barbadense). Three irrigation and two nitrogen fertilization levels were applied. Significant differences were observed among genotypes and environments for all fiber quality traits, with some year-to-year variation. Genotypic response for yellowness was influenced by fertilization. Across the two experimental years, a strong Fertilization × Environment interaction was observed, and in the second year, a Genotype × Fertilization × Environment interaction was detected for the uniformity index. Pa7 lines consistently outperformed Celia in fiber length (≈33 vs. 30 mm) and elongation (≈7.0 vs. 5.5%), while exhibiting higher yellowness values. Fiber strength, micronaire, uniformity, and reflectance varied between years but remained within acceptable ranges. Overall, Pa7 lines demonstrated superior fiber quality and stability under variable conditions, highlighting their potential for breeding programs. These findings support the importance of integrating interspecific germplasm with suitable irrigation–nitrogen management to improve cotton fiber performance and resilience under diverse cultivation environments. Full article

To address the challenges of layered fertilization in orchards and the lack of dedicated equipment, this study proposes a layered fertilization technique based on the three-dimensional distribution characteristics of jujube root systems and develops an orchard layered fertilizer applicator. First, the agronomic advantages of layered fertilization were systematically elucidated by analyzing the spatial distribution patterns of jujube roots, as well as the mechanisms of fertilizer nutrient transport and uptake. Second, parametric design was conducted for key components (e.g., trenching–fertilizing unit), with emphasis on the structural design of the fertilizer-dividing box and the augerless spiral conveying mechanism. A three-factor, three-level experiment based on response surface methodology was implemented, where the coefficient of variation (CV) of fertilization uniformity and row consistency were selected as evaluation indices to optimize key parameters (forward speed, augerless spiral speed, and fertilizer gate opening). The optimal operational combination was determined as follows: forward speed of 2.62 km/h, augerless spiral speed of 29.87 r/min, and fertilizer gate opening of 3.49 cm. Field tests demonstrated that the CVs of fertilization uniformity and row consistency reached 7.77% and 8.46%, respectively, meeting the agronomic requirements for orchard fertilization. This study provides a reference for the development of orchard fertilization technologies and machinery. Full article

Liriope muscari is a medicinal and ornamental herbaceous plant with significant economic value, as its tuberous roots are used for medicinal purposes. However, the current production of medicinal plants is characterized by wasteful use of resources and ecological risks caused by the unreasonable application of nitrogen fertilizers. In this study, based on uniform application of phosphorus and potassium fertilizers, six nitrogen application levels were set in pot experiments (expressed as N): N0: 0 kg/ha, N1: 208.33 kg/ha, N2: 416.66 kg/ha, N3: 625 kg/ha, N4: 833.33 kg/ha, N5: 1041.66 kg/ha). The morphological characteristics, photosynthetic physiology, tuber yield and quality, and seven nitrogen fertilizer utilization indices of L. muscari were analyzed and measured. Correlation analysis and structural equation modeling (SEM) were employed to investigate the mechanism by which nitrogen influences its growth and development, photosynthetic characteristics, tuber yield and quality, and nitrogen fertilizer utilization efficiency. The results showed that (1) nitrogen significantly promoted plant height, crown width, tiller number, and chlorophyll synthesis, with the N3 treatment (625 kg/ha) reaching the peak value, and the crown width and tiller number increasing by 26.44% and 38.90% compared to N0; the total chlorophyll content and net photosynthetic rate increased by 39.67% and 77.04%, respectively, compared to N0; high nitrogen (N5) inhibited photosynthesis and increased intercellular CO₂ concentration; (2) Fresh weight of tuberous roots, polysaccharide content, and saponin C content peaked at N3 (34.67 g/plant, 39.89%, and 0.21%), respectively, representing increases of 128.69%, 28.37%, and 33.66% compared to N0; (3) Nitrogen uptake, nitrogen fertilizer utilization efficiency, agronomic utilization efficiency, and apparent utilization efficiency were optimal at N3, while high nitrogen (N4–N5) reduced nitrogen fertilizer efficiency by 40–60%; (4) SEM analysis indicated that tiller number and transpiration rate directly drive yield, while stomatal conductance regulates saponin C synthesis. Under the experimental conditions, 625 kg/ha is the optimal nitrogen application rate balancing yield, quality, and nitrogen efficiency. Excessive nitrogen application (>833 kg/ha) induces photosynthetic inhibition and “luxury absorption”, leading to source-sink imbalance and reduced accumulation of secondary metabolites. This study provides a theoretical basis and technical support for the precise management of nitrogen in Liriope-type medicinal plants. It is expected to alleviate the contradictions of “high input, low output, and heavy pollution” in traditional fertilization models. Full article

This paper reviews technological advances in precision fertilizer application from 2020 to 2025, addressing the need for a systematic synthesis of recent innovations to support agricultural sustainability. With precision fertilization critical for efficient resource use, rapid technological progress in this field has highlighted a gap in consolidated overviews of post-2020 developments. The review focuses on three core areas: device innovation, intelligent control optimization, and simulation-driven parameter refinement. Key advancements include structural improvements in fertilizer applicators (e.g., multi-segment arc and variable-diameter designs) enhancing discharge uniformity and accuracy; integration of algorithms like PSO, fuzzy logic, and RBFNN (e.g., PSO-RBF-PID reducing flow control errors) boosting control precision; and DEM/CFD simulations optimizing device parameters. These technologies, applied in scenarios from drone-based unmanned operations to automatic targeting systems, have shown potential in reducing fertilizer use and increasing crop yields. This synthesis clarifies recent progress, offering insights for green agricultural development. Note that a few pre-2020 references are included for foundational context, ensuring completeness. Full article

China ranks as the world’s leading potato (Solanum tuberosum L.) producer, while the poor seeding machinery performance limited a higher input–output ratio in potato cultivation and impeded sustainable development. We developed an advanced air-suction mulai-arm potato planter (ASPP) that incorporated integrated side-deep fertilization, automated seed feeding, negative-pressure seed filling, seed transportation, positive-pressure seed delivery, soil covering, and compaction. The study proposes a Negative-pressure seed extraction mechanism that minimizes seed damage by precisely controlling suction pressure, and the near-zero-speed seed delivery mechanism synchronizes seed release with ground speed, reducing bounce-induced spacing errors. Furthermore, the structural configuration and operation principle of ASPP were systematically elucidated, and key performance parameters and optimal values were identified. We conducted a randomized complete block design plot trial comparing the spoon-belt potato planter (SBPP) and spoon-chain potato planter (SCPP), evaluating sowing quality, seedling emergence rate (ER), potato yield (PY), and comprehensive economic benefits. The results revealed that plant spacing index (PSI), missed-seeding index (MI), re-seeding index (RI), and coefficient of variation (CV) of ASPP were 90.05%, 3.78%, 2.32%, and 7.93%, respectively. The mean ER values for ASPP, SBPP, and SCPP were 94.76%, 85.42%, and 83.46%, respectively, with the ASPP showing improvements of 10.93% and 13.54% over SBPP and SCPP. However, the SBPP and SCPP exhibited greater emergence uniformity than ASPP. The mean PY value was 37,205.25, 32,973.75, and 34,620 kg·ha⁻¹ for ASPP, SBPP, and SCPP. The ASPP outperformed the SBPP and SCPP by 12.83% and 7.47%. Overall, ASPP demonstrated balanced and superior performance across the above-mentioned indicators, demonstrating its potential to enable precision agriculture in tuber crop cultivation. Full article

Choosing appropriate tillage methods and nitrogen application are important steps in the management of wheat production for obtaining high-yield and high-quality products, as well as managing the level of weed infestation. The aim of this research was to examine the impacts of three different tillage practices (conventional tillage—CT, mulch tillage—MT, and no tillage—NT), and two top dressing fertilization nitrogen levels (rational—60 kg ha⁻¹ and high—120 kg ha⁻¹) on the grain yield and quality of winter wheat, as well as on weed infestation. The present study was carried out in field experiments on chernozem luvic type soil at the Faculty of Agriculture Belgrade-Zemun Experimental field trial “Radmilovac”, in the growing seasons of 2020/2021–2022/2023. The C/N ratio in the soil was also assessed on all plots. The results showed that the number of weeds and their fresh and air-dry weights were higher on the MT and NT plots, compared to the CT plots. Therefore, the CT system has better effects on the yield (5.91 and 5.36 t ha⁻¹) and the protein content (13.3 and 13.1%). Furthermore, the grain weight per spike and the 1000-grain weight were higher in the wheat from the CT system (41.83 and 42.75 g) than from the MT (40.34 and 41.49 g) and NT (40.26 and 41.08 g) systems. Also, the crops from the CT system had higher values of grain density and grain uniformity compared to the crop from the MT and NT systems. Fertilization with a high nitrogen level (120 kg ha⁻¹) causes higher grain yield and more weediness compared with the rational level (60 kg ha⁻¹). Top dressing fertilization in each tillage system resulted in an increase in the number of weeds, but, at the same time, it also resulted in stronger competitive ability of the wheat crop against weeds. The most favorable C/N ratio occurred on the NT plots, and the least beneficial one on the CT ones. A correlation analysis showed strong negative correlations of number (r = −0.82) and fresh weed mass (r = −0.72) with yield. It is concluded that the conventional tillage practice with a low nitrogen dose manifests its superior performance in minimizing weed infestation and maximizing crop productivity. Full article

Variable-rate nitrogen (VR-N) application allows farmers to optimize nitrogen (N) input site-specifically within field boundaries, enhancing both economic efficiency and environmental sustainability. In this study, VR-N technology was applied to durum wheat in two small-scale commercial fields (3–4 ha each) located in distinct agro-climatic zones of Thessaly, central Greece. A real-time VR-N application algorithm was used to calculate N rates based on easily obtainable near-real-time data from unmanned aerial vehicle (UAV) imagery, tailored to the crop’s actual needs. VR-N implementation was carried out using conventional fertilizer spreaders equipped to read prescription maps. Results showed that VR-N reduced N input by up to 49.6% compared to the conventional uniform-rate N (UR-N) application, with no significant impact on wheat yield or grain quality. In one of the fields, the improved gain of VR-N when compared to UR-N was 7.2%, corresponding to an economic gain of EUR 163.8 ha⁻¹, while in the second field—where growing conditions were less favorable—no considerable VR-N economic gain was observed. Environmental benefits were also notable. The carbon footprint (CF) of the wheat crop was reduced by 6.4% to 22.0%, and residual soil nitrate (NO₃⁻) levels at harvest were 13.6% to 36.1% lower in VR-N zones compared to UR-N zones. These findings suggest a decreased risk of NO₃⁻ leaching and ground water contamination. Overall, the study supports the viability of VR-N as a practical and scalable approach to improve N use efficiency (NUE) and reduce the environmental impact of wheat cultivation which could be readily adopted by farmers. Full article

Natural mating colony cages are crucial in poultry breeding, yet breed-specific management requires further investigation. We evaluated the effects of sex ratios, stocking densities, and cohabitation age on Lohmann Pink-shell breeders’ performance. A total of 6126 birds were randomly allocated to experimental groups with varying ratios (1:8–1:13), densities (582–748 cm²/bird), and cohabitation ages (120/140 days), each containing six replicates. We monitored male mating frequencies at 50 weeks in 1:8 and 1:10 ratio groups. All 120-day-old groups showed delayed production onset and superior male weight compliance (p < 0.01), with reduced egg breakage and increased healthy chick output (p < 0.01). Lower stocking densities (748/694 cm²/bird) showed lower breakage rate and uniformity than 582 cm²/bird (p < 0.05). The 1:10 sex ratio achieved optimal egg production and fertilization rate (p < 0.05). Male mating peaked between 16:00 and 18:00. Optimal parameters were 120-day age of cohabitation, 694 cm²/bird density, and 1:10 sex ratio, providing theoretical guidance for natural mating colony cage development in layer breeding. Full article

Aiming at the existing fertilizer distributor’s lack of stability of fertilizer discharge and uniformity of fertilizer discharge, which affects the precise application of fertilizer, a design and testing of a multi-row spiral quantitative fertilizer distributor was designed. The design principle and working principle of the fertilizer distributor are described, and the parameter ranges of centrifugal cone discs’ cone angle, cone disc inclination, cone disc rotation speed, etc., are determined. The Elementary Discrete Element Method (Referred to as EDEM in the following) simulation analysis software was adopted to carry out the simulation analysis of the fertilizer discharge process of the fertilizer discharger, to study the influence of each parameter on the fertilizer discharge performance and the optimal combination parameters of the fertilizer discharger. Taking the coefficient of variation for the consistency of fertilizer application amount among rows and the coefficient of variation for the consistency of fertilizer application amount within the same row as the evaluation indicators, and taking the cone angle of the centrifugal cone disk, the cone disk inclination angle, and the cone disk rotational speed as the test factors, multi-factor and multi-level experiments were carried out. The simulation test results show that the optimal parameter combination of the fertilizer discharger is the rotational speed of the centrifugal cone disk at 95 r/min, the cone angle of the cone disk at 16.7°, and the blade inclination angle of the cone disk at 2.7°. Using potassium sulphate compound fertilizer as the test material, the bench test on the fertilizer discharge performance and adaptability of the fertilizer distributor when the speed of centrifugal cone discs was 30~110 r/min was carried out to verify the fertilizer discharge performance of the fertilizer distributor. The results of the validation test showed that the coefficient of variation for the consistency of fertilizer application amount among rows of fertilizer distributor at different rotational speeds was lower than 4.25%, the coefficient of variation for the consistency of fertilizer application amount within the same row was lower than 3.21%, which meets the requirement of fertilizer discharge quality. The research provides technical support for enhancing the performance of fertilizer distributors and achieving precise fertilizer application, thereby playing an active role in improving fertilization efficiency and promoting sustainable agricultural development. Full article

Water scarcity in Brazil’s semi-arid region necessitates the agricultural reuse of aquaculture effluents, although emitter clogging remains a challenge. This study evaluated clogging mitigation in drip irrigation systems using liquid anti-clogging fertilizer. The experiment employed a split–split–plot scheme with three water treatments (supply water, aquaculture effluent, and effluent with liquid fertilizer) and three emitter types (ST, SL, and GA), assessing performance over 360 h. A water quality analysis at 0, 160, and 360 h complemented hydraulic evaluations of the average flow rate variation and Christiansen uniformity coefficient measured every 40 h. Energy-dispersive X-ray spectroscopy, X-ray diffractometry, and scanning electron microscopy were used to characterize biofouling. The results showed that the liquid fertilizer mitigated the clogging by biofouling in the three types of emitters, but only the ST emitter presented acceptable hydraulic performance rates. There are relationships between the anti-clogging effect of the liquid fertilizer, the structural characteristics of the emitters, and the flow velocity inside the labyrinths. The SL dripper applying only aquaculture effluent presented the highest clogging rate due to biofouling. Agricultural reuse is a strategy for the rational use of water resources that is of great relevance for arid and semi-arid regions and can insert aquaculture into the circular economy. Full article

The bivariate fertilizer applicator (BAF) is a crucial device for precision agriculture, and the optimization of the control sequence optimization (CSO) significantly impacts the performance of variable-rate fertilization (VRF). This study investigates the CSO problem as a multi-objective optimization problem (CSO-MOP) for BFA through the lens of balanced trade-offs among conflicting objectives, including fertilization accuracy, uniformity, and adjustment rapidity. We employed three multi-objective evolutionary algorithms (MOEAs), including NSGA-III, MOEAD-D, and AR-MOEA. To investigate the problem, we solved several instances for different target fertilization rates and selected appropriate evaluation metrics. Finally, we obtained the Pareto set (PS) from each MOEA and conducted a comparative analysis, including the performance of each algorithm in addressing the CSO-MOP, the conflicts between each pair of objectives, and the effects of the optimized control sequences derived from each algorithm on the three objectives. Full article