Utilization Rate Of Pesticides Research Articles

Tank-Mix Adjuvants Regulate the Deposition, Absorption, and Permeation Behavior of Pesticide Solutions on Rice Plant

Pesticide foliage treatment is used in agricultural production to protect plants from diseases, pests, or weeds. Tank-mix adjuvants added to the barrel can improve the effective utilization rate of pesticides. Herein, a comparative study was conducted to investigate the effect of three kinds of tank-mix adjuvant on the deposition, absorption, and permeation behavior of epoxiconazole and chlorantraniliprole solutions. Surface tension and contact angle results indicate that polyether-modified trisiloxane may be the best surface-active agent for pesticides, whereas methyl oleate and green-peel orange essential oil were found to be more suitable for improving pesticide deposition, absorption, and permeation in some cases. These findings indicate that various tank-mix adjuvants had different effects on pesticide application on plants. Appropriate tank-mix adjuvants need to be selected for comprehensive practical application.

Research on Methods Decreasing Pesticide Waste Based on Plant Protection Unmanned Aerial Vehicles: A Review

In plant protection, the increasing maturity of unmanned aerial vehicle (UAV) technology has greatly increased efficiency. UAVs can adapt to multiple terrains and do not require specific take-off platforms. They do well, especially in farmland areas with rugged terrain. However, due to the complex flow field at the bottom of a UAV, some of the droplets will not reach the surface of a plant, which causes pesticide waste and environmental pollution. Droplet deposition is a good indicator of the utilization rate of pesticides; therefore, this review describes recent studies on droplet deposition for further method improvement. First, this review introduces the flight altitude, speed, and environmental factors that affect pesticide utilization efficiency and then summarizes methods to improve pesticide utilization efficiency from three aspects: nozzles, electrostatic sprays, and variable spray systems. We also point out the possible direction of algorithm development for a UAV’s precision spray.

Comparison of the Effects of Chemical Topping Agent Sprayed by a UAV and a Boom Sprayer on Cotton Growth

In order to improve the spraying efficiency of cotton chemical topping agents, a field experiment was conducted to compare the effects of 250 g·L−1 mepiquat chloride aqueous solutions sprayed by a T30 unmanned aerial vehicle (UAV) and a boom sprayer. The cotton agronomic parameters, pesticide utilization rate, yield, and fiber quality were determined. The results showed that the pesticide utilization rates of the T30 UAV and the boom sprayer were 48.71% and 30.37%, respectively. After 10, 20, 30, and 40 days of T30 UAV spraying, the plant height inhibition rates of the two varieties of cotton were 12.97%, 13.78%, 20.91%, and 26.14% for Xinluzao 52 and 8.64%, 13.37%, 14.72%, and 18.03% for Huiyuan 720. After spraying with a boom sprayer, the plant height inhibition rates were 7.94%, 11.13%, 18.23%, and 23.69% for Xinluzao 52 and 6.09%, 9.98%, 11.78%, and 15.14% for Huiyuan 720 after 10, 20, 30, and 40 days of spraying. The T30 UAV spraying chemical topping agent was shown to have a significant beneficial effect on the utilization rate of the pesticides, as well as the agronomic properties, yield, and the fiber quality of the cotton.

Efficient polymer-mediated delivery system for thiocyclam: Nanometerization remarkably improves the bioactivity toward green peach aphids.

The unscientific application of synthetic pesticides has brought various negative effects on the environment, hindering the sustainable development of agriculture. Nanoparticles can be applied as carriers to improve pesticide delivery, showing great potential in the development of pesticide formulation in recent years. Herein, a star polymer (SPc) was constructed as an efficient pesticide nanocarrier/adjuvant that could spontaneously assemble with thiocyclam or monosultap into a complex, through hydrophobic association and hydrogen bonding, respectively, with the pesticide-loading contents of 42.54% and 19.3%. This complexation reduced the particle sizes of thiocyclam from 543.54 to 52.74 nm for pure thiocyclam, and 3814.16 to 1185.89 nm for commercial preparation (cp) of thiocyclam. Interestingly, the introduction of SPc decreased the contact angles of both pure and cp thiocyclam on plant leaves, and increased the plant uptake of cp thiocyclam to 2.4-1.9 times of that without SPc. Meanwhile, the SPc could promote the bioactivity of pure/cp thiocyclam against green peach aphids through leaf dipping method and root application. For leaf dipping method, the 50% lethal concentration decreased from 0.532 to 0.221g/L after the complexation of pure thiocyclam with SPc, and that decreased from 0.390 to 0.251g/L for cp thiocyclam. SPc seems a promising adjuvant for nanometerization of both pure and cp insecticides, which is beneficial for improving the delivery efficiency and utilization rate of pesticides.

Functionalized halloysite nanotubes as chlorpyrifos carriers with high adhesion and temperature response for controlling of beet armyworm

Intelligent responsive pesticide delivery systems have been used in agricultural applications to improve pesticide utilization. To improve the bioavailability of pesticides for combating the growth of beet armyworm (which grows fastest at 35°C), we constructed a halloysite nanotubes (Hal)-based sustained release system with intelligent temperature-responsive release properties and strong adhesion to leaves. Hal, N-isopropylacrylamide (NIPAm), dopamine (DA, polydopamine is abbreviated as PDA) and chlorpyrifos (CPF) were used as the raw materials to prepare (PNIPAm-g-Hal)@CPF@PDA (PHCP). PHCP had excellent thermosensitive release performance, and the average release rate at 35°C was approximately 2.5 times higher than that at 25°C. Through a simulated rainwater scour experiment, the retention rate of PHCP on corn leaves was 83.52% (2.25 times higher than that of (PNIPAm-g-Hal)@CPF) (PHC). The continuous release time of CPF from PHCP was more than 60 h. PHCP improved the UV-shielding performance of CPF, and it took 12 times longer than the original CPF to reach the same degradation rate. This study demonstrates a strategy to design pesticide carriers according to the characteristics of the target, which is widely applicable to protect crops, improve the utilization rate of pesticides, and protect the environment.

Polylactic acid nanoparticles for co-delivery of dinotefuran and avermectin against pear tree pests with improved effective period and enhanced bioactivity

Pesticide compounding technology for disease and pest control emerges as an effective way to increase the effectiveness of pesticides while reducing pesticides resistance. Nanomaterials and encapsulation technology have offered a new insight into preparing efficient pesticide formulations, especially constructing a co-delivery nanoparticle for synergistic pesticides. In this study, a dinotefuran/avermectin co-delivery nanoparticles (DACNPs) against pear tree pests with polylactic acid (PLA) as the wall material were constructed by double-emulsion method combined with high-pressure homogenization technique. The drug content of the DACNPs was 39.1% with an average size of 245.7 ± 4.2 nm and the mean polymer dispersity index (PDI) value was 0.123. The DACNPs showed high foliar retention and good spread performance on target leaves due to the nanoscale effect. The obtained DACNPs showed a better control effect on Grapholitha molesta Busck and Psylla chinensis Yang et Li compared with the commercial formulations, which could significantly prolong the effective duration and enhance the bioactivity with lower amounts and application frequency of pesticides. This study may provide new insights into developing novel pesticide formulations to improve the utilization rate of pesticides, reduce environmental pollution and minimize the cost of farming.

Feedback regulation system for spraying parameters based on online droplet mass deposit measurements

In order to effectively optimize and regulate spraying parameters based on actual spraying performance and improve pesticide utilization rate, in this research, a feedback regulation system for the regulation of spraying parameters was designed based on droplet mass deposit online measurement. The system consisted of an online droplet mass deposit measurement module, wireless transmission module, decision module, and spraying parameters regulation module. First, the droplet mass deposits on the sampling points were measured. Based on the deviation between the measured and expected droplet mass, the expected spraying parameters were determined by the decision module. The spraying parameter was regulated to the expected value by regulating the pulse duty cycle on the pump motor using a micro control unit and a relay. Evaluation tests were conducted indoors using an indoor spraying platform and outdoors using an unmanned aerial vehicle. The results showed that the relative errors between the expected and measured droplet mass deposit after regulation were 6.84% and 11.48% for the indoor and outdoor tests, respectively. Therefore, an optimal spraying performance was observed after regulation. This research provided an experimental platform to quickly optimize spraying parameters and also provided technical references for precision spraying. Keywords: spray, droplet mass deposit, online measurement, wireless transmission, duty cycle, feedback regulation DOI: 10.25165/j.ijabe.20221502.6118 Citation: Sun C D, Qiu W. Feedback regulation system for spraying parameters based on online droplet mass deposit measurements. Int J Agric & Biol Eng, 2022; 15(2): 25–29.

Design and Test of a Jet Remote Control Spraying Machine for Orchards

Aimed at issues associated with the poor air supply and poor automatic targeting accuracy of existing orchard sprayers, this paper designs a jet-type orchard remote control sprayer with automatic targeting which is suitable for standardized orchards in hilly and mountainous areas. By optimizing the structure of the diversion box, the uniformity of deposition and penetration ability of the pesticide droplets to the fruit tree canopy are improved, and a uniform wild field distribution is realized simultaneously. An accurate positioning of the fruit tree canopy space orientation is achieved through automatic targeting and azimuthal adjustment systems. When the target is detected, the solenoid valve is controlled to open, and vice versa, and the distance from the nozzle to the fruit tree canopy is adjusted in real time to improve the utilization rate of pesticides. The test results show that the effective range of the jet-type orchard remote control sprayer is no more than 3.5 m, and the maximum flow rate range is 6~6.5 L/min. Within the effective spraying range, the farther the distance is, the higher the automatic targeting accuracy. The pesticide droplets sprayed by the spraying machine have a certain penetration ability, and the uniformity of the droplets is good, which solves solidification problems caused by the penetration of pesticide into the soil. This research provides a reference for jet spraying operation and automatic targeting spraying structure design.

Dinotefuran nano-pesticide with enhanced valid duration and controlled release properties based on a layered double hydroxide nano-carrier

A dinotefuran layered double hydroxide (D-LDH) nano-pesticide is designed via a supramolecular self-assembly method. It improved the utilization rate of pesticide and enhanced the valid duration.

An efficient organosilane-modified polycarboxylate dispersant with excellent dispersing performance and superior wettability for tebuconazole suspension concentrate

The dispersion stability and wettability of suspension concentrates are beneficial for improvement of the utilization rate of pesticides.

Optimization Design of Online Mixing Apparatus and Mixing Performance Experiment for Crop Protection Equipment

At present, the premixing method is used in the operation of plant protection machines. Premixing and dispensing often lead to uneven proportioning and mixing, thereby reducing the utilization rate of pesticides. There is a great potential safety hazard. In order to improve the effective utilization rate of pesticides in spray operations, an online hybrid system is designed. Based on the theory of computational fluid dynamics, the static mixer model with built-in spoiler was established, and the numerical analysis was carried out by using FLUENT software. The simulation results were analyzed by evaluating the coefficient of variation of mixing uniformity and consistency. Under pressure, the coefficient of variation of pesticide solution mixing was 3.2%. Then carmine solution was used to replace pesticide, and UV spectrophotometry was used to test. The results show that the maximum relative error of mixing stability at the nozzle of the mixing system is 4.301% and the maximum coefficient of variation of pesticide solution is 3.989% under pressurized condition. The experimental coefficient of variation is basically consistent with the simulation results. Practice has proved that the designed online hybrid system has good mixing effect and can be used for the later stage variable spray test of plant protection equipment.

Application of imidacloprid controlled-release granules to enhance the utilization rate and control wheat aphid on winter wheat

During winter wheat production, aphids need to be controlled with pesticides for the entire growth period. Controlled-release technology has been regarded as an alternative method for the improvement of pesticide efficiency. This study investigated two types of imidacloprid controlled-release granule (CR-GR): 2% imidacloprid CR-GR and 0.2% imidacloprid pesticide-fertilizer controlled-release granule (PF-CR-GR) when wheat was sown in winter. The release performance, utilization rate, terminal residues in edible parts, control effect on aphids, and achieved winter wheat yield were evaluated for both laboratory experiments and field application. Imidacloprid PF-CR-GR released more quickly in aqueous medium than CR-GR because of its good water solubility. After CR-GR treatments, the concentrations in wheat roots and soil were similar throughout the entire sampling period, and the concentrations in shoots were about 10–20% of those in roots. Imidacloprid was better absorbed when CR-GR was used as root treatment, compared with foliar treatment. Field application showed that imidacloprid CR-GR and PF-CR-GR controlled aphids throughout the entire growth period of winter wheat and improved the wheat yield. These findings identified application of imidacloprid CR-GR and PF-CR-GR on winter wheat as an effective way to enhance the pesticide utilization rate and ensure adequate yield. This paper provides a theoretical basis for the scientific use of pesticides and guides scientific pesticide application.

Analysis of Spray Uniformity of Sprayers Based on Deep Belief Network

Improving spray quality has a important practical significance for controlling the drift of harmful substances, increasing the effective utilization rate of pesticides and reducing environmental pollution. The influence of factors on spray quality is analyzed, and the nozzle wear is regarded as one of the influencing factors for the first time in this paper. It also constructs the relationship between spray distribution uniformity and influencing factors Model by proposes a soft measurement method based on deep belief network. Besides, when the distribution coefficient of variation and another influencing factors is given, the pressure value corresponding to them can get by neural network inverse modeling method, And the pressure can be used as the controlled variable in the spraying process. Compared to BP, the DBN model has stronger nonlinear mapping capabilities, higher prediction accuracy, and high practical value.

Numerical Simulation on Deposition of Atomization Droplet of Air-assist Boom Spraying in Air Flow

Air-assist Boom Spraying is a crucial technique and spray method of plant protection which has a significant effect on improving the efficiency of pesticide application and reducing droplet drift. Spraying drift is the main reason for the low utilization rate of pesticides, at the same time, the interaction of natural wind and the air bag wind is the main cause of spray drift. But at present, the regularity of spray droplet deposition and motion trajectory under the common influence of natural wind and air bag wind is not yet clear. The kinematics characteristics of the droplets deposition of air-assist boom spraying in the plants is investigated with numerical simulation method. The Phase Doppler Particle Analyzer (PDPA) is used to validate the numerical simulation results and it indicates that the deposition process can be well reproduced. The results show that the bigger droplets (>150 μm) get more kinetic energy from the vertical airflow and locate in windward side. These droplets are not sensitive to the horizontal airflow and are easier to deposit within a short time. The droplets with smaller size (<150 μm) are minimally influenced by the vertical airflow and suspend in the upside of the flow field. The vertical airflow not only prevents the horizontal airflow drift the droplets, but also introduces a vortex region near the canopy of the plants, which rotates the plant canopy and increases the droplet deposition on backside of the leaves. This study improves the understanding of the droplets deposition under the multi-wind fields and provides the theoretical basis for the innovation of the air-assist boom spraying system.

An eco-friendly MIL-101@CMCS double-coated dinotefuran for long-acting active release and sustainable pest control

Long-acting release systems of pesticide have been shown great potential in agricultural production, as well as environmental protection. However, the current systems for pesticide controlled-release are still many problems, such as the fast drug release in the early stages, and insufficient drug release in late periods, which cannot actively and efficiently control pests. Herein, an eco-friendly active controlled-release system, dinotefuran@FeCl2(H2O)2O(BDC)3@carboxymethyl chitosan (DNF@MIL-101@CMCS) was successfully prepared by chemical crosslinking. In which, take CMCS as the outer layer, MIL-101 as the inner layer, double layer coated DNF. Its properties of active controlled-release and sustainable anti-pest activity were investigated. As a result, the loading capacity of MIL-101@CMCS to DNF was as high as 24.5%. The DNF of 14.3% was firstly released from the outer layer (CMCS) to achieve early preliminary release. In the late period, the DNF of 83.1% was active released from the inner layer (MIL-101) stimulated by citric acid to achieve long-acting active release. Subsequently, the soil pot experiment results showed that the combination of long and short effect of DNF@MIL-101@CMCS could achieve a long-acting anti-pest activity within 41 days of the entire pest outbreak. Besides, under UV irradiation, the anti-photolysis capacity of DNF protected by MIL-101@CMCS was improved 3.4 times higher than that of uncoated DNF. Therefore, this work provided a promising approach to change the traditional passive release for the active release and improve the utilization rate of pesticide, which is completely consistent with the purpose of cleaner production in agriculture.

Experimental evaluation of UAV spraying for peach trees of different shapes: Effects of operational parameters on droplet distribution

Small-scale plant protection Unmanned Aerial Vehicles (UAVs) are finding a wide range of appli cations in modern agriculture management (including aerial spraying) due to their high efficiency and flexibility, low labour/water requirement and no damage to crops and soils, which substantially increase agricultural productivity and sustainability. UAV operational parameters, however, have remarkable effects on droplet distribution in UAV spraying, which significantly affect pesticide utilization rate and treatment effectiveness. Therefore, this work aimed to evaluate the effects of UAV operational parameters on droplet distribution for orchard trees. In particular, peach, an important orchard tree worldwide, is investigated in this study, and two typical tree shapes were considered including Y-shape and Central Leader (CL)-shape. Specifically, UAV spraying experiments were performed in Shandong Institute of Pomology, Shandong Province, China, and gas powered helicopter 3WQF120-12 was chosen as the spraying platform. The UAV operational parameters under consideration include flight route (intra-row, inter-row), flight velocity (four levels: 2, 3, 4, 5 m/s), number of spray times (1 vs 2) and nozzle flow rate. Droplet coverage rate at different positions and layers, obtained by water sensitive papers, was chosen as the metric to evaluate spraying performance. Experimental results show that: (1) the spraying uniformity is different between Y-shape and CL-shape peach tree, where Y-shape exhibits uniformity for positions at inner or outer layers. CL-shape results in a higher droplet coverage at top layer while with uniformity at lower three layers; (2) for Y-shape peach, intra-row route obtained a higher droplet coverage rate; while for CL-shape peach inter-row not only saved spraying volume but also results in a higher droplet coverage rate; (3) for both tree shapes, the increase in flight velocity (2–5 m/s) significantly decreased the droplet coverage rate; (4)for Y-shape peach with doubling the number of spraying times decreased the spraying performance for unit area.(5) for CL-shape peach with intra-row route, increasing the nozzle flow rate from 1.8 to 2.2 L·min-1 can significantly improve the droplet coverage rate at top and bottom two layers. It is envisioned that this study can provide some fundamental guidance of the operation of small UAVs for the aerial spraying of peach trees and similar orchards.

Numerical Simulation and Experimental Verification of the Deposition Concentration of an Unmanned Aerial Vehicle

Abstract. To analyze the droplet deposition under the influence of the flow field of an unmanned aerial vehicle (UAV), a hand-held three-dimensional (3D) laser scanner was used to scan 3D images of the UAV. Fluent software was used to simulate the motion characteristics of droplets and flow fields under the conditions of a flight speed of 3 m/s and an altitude of 1.5 m. The results indicated that the ground deposition concentration in the nonrotor flow field was high, the spray field width was 2.6 m, and the droplet deposition concentration was 50 to 200 ug/cm2. Under the influence of the rotor flow field, the widest deposition range of droplets reached 12.8 m. Notably, the droplet deposition uniformity worsened, and the concentration range of the droplet deposition was 0 to 500 ug/cm2. With the downward development of the downwash flow field, the overall velocity of the flow field gradually decreased, and the influence interval of the flow field gradually expanded. In this article, the droplet concentration was verified under simulated working conditions by a field experiment, thereby demonstrating the reliability of the numerical simulation results. This research could provide a basis for determining optimal UAV operating parameters, reducing the drift of droplets and increasing the utilization rate of pesticides. Keywords: Unmanned aerial vehicle (UAV), Aerial application, Downwash flow field, Droplet deposition, Simulation analysis.

Natural green-peel orange essential oil enhanced the deposition, absorption and permeation of prochloraz in cucumber.

Pesticides have long been used in agricultural production and will continue to be used long into the future. Enhancing their efficient use in agricultural production is an effective method to avoid their loss to non-target areas, such as soil, water and air. Here natural green-peel orange essential oil (GOEO) was used as a spray adjuvant to improve the efficient use of pesticides. A comparative study between a conventional formulation and a conventional formulation with GOEO was conducted. Conventional formulations of prochloraz were chosen as control groups. It was obvious that the concentrations of prochloraz and its metabolite in cucumber leaves treated by conventional formulations with GOEO were much higher than those treated without GOEO. The data also showed, for both emulsifiable concentrate (EC) and suspension concentrate (SC), that the spreading and penetration performance were improved when GOEO was used as a spray adjuvant, but with SC the impact was more significant. GOEO improved the deposition, absorption and degradation performance of prochloraz on cucumber leaves. It was more applicable to those pesticide formulations without a good wetting and spreading effect, such as SC. As a plant source extract, GOEO is much safer for crops and more friendly to the environment than other synthetic adjuvants. The application of GOEO as a spray adjuvant has great potential to increase the pesticide utilization rate.

Enhancement of Spirotetramat Transfer in Cucumber Plant Using Mesoporous Silica Nanoparticles as Carriers.

Pesticides will be used for a long period of time, and their use may cause environmental contamination and adverse effects on human health. The aim of this study was to improve the utilization rate of pesticides and reduce the risk to the environment using mesoporous silica nanoparticles (MSNs) as carriers. Compared to the conventional formulation, spirotetramat-loading MSNs improved deposition, uptake, and translocation performance in cucumber plants. MSNs may hold spirotetramat in their mesoporous structure and prevent its degradation in plants. The final residue of spirotetramat and its metabolites demonstrated that spirotetramat-loading MSNs had low risk to the edible parts of plants under foliar application. This study added our knowledge of MSNs controlling pesticide release and transfer in plant.

Preparation of MSNs-Chitosan@Prochloraz Nanoparticles for Reducing Toxicity and Improving Release Properties of Prochloraz

Nanotechnology-based pesticide formulations can improve the utilization rate of pesticides and reduce their negative effects on the environment. In this work, prochloraz was encapsulated within the...