Spray Mixture Research Articles

Pesticide and Adjuvant Mixture Impacts on the Physical–Chemical Properties, Droplet Spectrum, and Absorption of Spray Applied in Soybean Crop

Tank mixing of pesticides, a common practice in many countries, when performed incorrectly, can negatively impact the effectiveness of the pesticides. This study aimed to investigate the physical–chemical properties, droplet spectrum, and absorption by soybean plants of mixtures of the azoxystrobin fungicide with glyphosate herbicide and different adjuvants (mineral oil, propionic acid, and orange oil). The study design was completely randomized, with five treatments (T): T1, only fungicide; T2, fungicide + glyphosate; T3, fungicide + mineral oil; T4, fungicide + propionic acid; and T5, fungicide + orange oil. The spray concentrations simulated an application rate of 160 L ha−1 using the TT110015 nozzle. The physical stability, hydrogen ion potential, electrical conductivity, surface tension, droplet spectrum, and azoxystrobin absorption in soybean plants were evaluated. To measure absorption, soybean plants were sprayed at the reproductive growth stage, and leaf samples were collected after 0, 2, and 48 h. The amount of azoxystrobin absorbed was determined using gas chromatography. The results indicated that the spray mixtures were physically compatible. All mixtures produced a medium droplet spectrum. T2 had the lowest absorption percentages, suggesting that these pesticides should not be mixed. Adjuvants increased the amount of azoxystrobin absorbed by the plants, and it took 2 h on average for the soybean leaves to absorb 72.58% of the applied spray.

A comparative study of 10% lidocaine spray versus eutectic mixture of 2.5% lidocaine and 2.5% prilocaine (EMLA) to attenuate pain of peripheral venous cannulation in children: A prospective randomized control trial at a tertiary care centre.

Eutectic mixture of local anesthetics (EMLA) (2.5% lidocaine and 2.5% prilocaine) cream is the commonly used topical anesthetic for painful intradermal procedures. Topical 10% lidocaine spray has successfully been used to anesthetize mucosal surfaces. Owing to its skin penetrative properties, this study was conducted to compare dermal analgesia between 10% lidocaine spray and EMLA cream for intravenous (IV) cannulation in children. In this prospective single-blind randomized study, ninety-nine Paediatric patients were assigned into Group A (number(n) =51) with Lignocaine 10% spray applied 10 minutes and Group B (n = 48) EMLA cream applied 1 hour prior to cannulation. Vital signs were recorded before, during, and after the procedure. The primary objective of the study was assessment of severity of pain during IV cannulation using 10 cm visual analogue scale (VAS). Secondary objectives such as ease of cannulation and adverse effects were also noted. All cannulations were performed in the first attempt with no adverse effects in both lidocaine group and EMLA group. The median (interquartile range) VAS score was 2 cm (1 to 3) in both the groups with a P value of 0.58. Topical 10% lidocaine spray applied ten minutes before venous cannulation is as effective as EMLA cream applied an hour before cannulation in children in providing dermal analgesia for intravenous cannulation with an added advantage of rapid onset of action in the former group.

A Turbidity Module to Measure Spray Mixture Concentration for Premixing In-Line Injection System

Highlights A turbidity sensor module was investigated to monitor concentrations of pesticide mixtures in real time. A flow-through measurement platform was built to calibrate the turbidity sensor and determine its accuracy. Optimal location of the turbidity sensor was determined for monitoring in-line mixture concentrations. Spray mixture uniformity reached acceptable level for the premixing in-line injection system. Abstract. Monitoring mixture concentrations for precision pesticide spray systems in real time can assure the desired amount of chemicals distributed uniformly to target areas. An in-line turbidity sensor module was investigated to monitor concentrations of spray mixtures produced with a premixing in-line injection system developed for precision variable-rate orchard sprayers. The turbidity sensor was calibrated with simulated pesticides at concentrations ranging from 0% to 30.0%. A cubic polynomial regression model was established for the relationship between sensor output voltages and mixture concentrations. Sensors were mounted at three in-line locations to detect the mixture uniformity differences in the premixing in-line injection system. The module was found to have adequate precision and accuracy to measure concentrations of spray mixtures with simulated pesticides. Relative errors of the sensor were less than 4.70% and the sensor accuracy did not vary with mixture flow rates. Mounting the turbidity sensor downstream of the buffer tank in the premixing in-line injection system would be the optimal location to monitor spray mixture uniformity for variable-rate spray applications. At this location, the relative errors of measured mixture concentrations were between 0.12% and 3.70% which agreed with previous manual measurements. Therefore, there would be a great potential to integrate the in-line turbidity sensor into the variable-rate and even conventional constant-rate sprayers to achieve uniform spray applications in the target field. Keywords: Agitation, Mixture uniformity, Pesticide concentration, Sensor calibration, Variable-rate sprayer.

Air-Pinch PWM Valve to Regulate Flow Rate of Hollow-Cone Nozzles for Variable-Rate Sprayers

Highlights Air-pinch PWM valve was investigated as an alternative to electric PWM valves to manipulate hollow-cone nozzles. Air-pinch and electric PWM valves performed comparable accuracy in flow rate modulations. Droplet sizes from hollow-cone nozzles with both PWM valves were comparable across DUCs ranging from 20% to 100%. Air-pinch PWM valve had great potential of use due to its capacity to isolate the internal parts of the valve from chemicals. Abstract. Electric pulse width modulation (PWM) solenoid valves are commonly used to regulate nozzle flow rates to achieve precision variable-rate spray applications. However, some pesticide formulations, such as wettable powders and adhesive additives, can potentially cause a malfunction such that the valve cannot completely shut off during flow rate modulation if spray lines are not cleaned thoroughly after spray applications. An air-pinch PWM valve was evaluated as a potential alternative to conventional PWM valves to modulate the flow rates of hollow-cone nozzles used on air-assisted orchard sprayers. With the air-pinch valve, spray mixtures only passed through a flexible tube to avoid chemicals directly contacting the moving components inside the valve chamber. The flow rate modulation was performed by pinching and releasing the tube back and forth with air-pilot PWM actions. Evaluations included the flow rate modulation capability along with droplet size distributions from three disc-core hollow-cone nozzles coupled with the PWM pinch valve and compared with a conventional electric PWM valve. Both air-pinch and electric PWM valves performed comparably in the flow rate modulation accuracy and droplet size distribution for hollow-cone nozzles operated at 414 and 827 kPa pressures across the duty cycles (DUCs) ranging from 10% to 100%, except for the air-pinch valve that could not activate at 10% DUC. The flow rates of nozzles modulated with both PWM valves at all DUCs were 5.3% greater on average than the target flow rates, while the flow rates were similar at 90% and 100% DUCs. Droplet size classifications based on ASABE Standard S-572.3 were generally consistent across DUCs ranging from 20% to 100% for the same nozzle and pressure with the air-pinch PWM valve and from 10% to 100% with the conventional electric PWM valve. The consistency of droplet sizes across DUCs and accuracy of flow rate modulations demonstrated the potential advantage of using the air-pinch PWM solenoid valve as an alternative for precision variable-rate sprayers to accurately apply different chemicals. Keywords: Droplet size, Flow rate control, Pesticide, Pinch valve, Precision farming, Pulse width modulation.

Agronomic assessment of the herbicides application on winter wheat crops

In modern conditions of agricultural production, it is important to obtain a high yield of good quality, which may be limited by a high degree of contamination of crops. At the same time, it is necessary to search for new approaches to the weed control problem, which involves solving a number of issues: determining and analyzing the floral composition of weeds with constant monitoring of contamination to make forecasts and make operational decisions. This work is devoted to the study of these issues. It reveals the features of winter wheat agrophytocenosis formation with the analysis of weed species composition, and shows the effectiveness of the use of herbicides recommended on the basis of mapping. The biological efficiency of the spray mixture of herbicides Verdict + Dinat was 84.1% (by the number of weeds) and 94.9% (by air-dry weight). The agronomic effectiveness of herbicides was expressed in obtaining an increase in yield of 2.67 t/ha, and the profitability level was above the threshold of economic feasibility of the weed management and amounted to 141.8%.

Pilot diesel-ignited ammonia dual fuel low-speed marine engines: A comparative analysis of ammonia premixed and high-pressure spray combustion modes with CFD simulation

Decarbonization of global shipping plays an important role in avoiding the worst impacts of climate change, and ammonia is a promising sustainable and zero-carbon fuel in the maritime sector. The dual-fuel mode has the potential to compensate for the poor combustion property of ammonia, but the existing studies are mainly focused on automotive medium- and high-speed engines, researches on marine low-speed engines are rarely reported. In this paper, the numerical models of pilot diesel-ignited ammonia dual fuel engine under both the premixed and high-pressure spray combustion modes are established using a commercial low-speed marine diesel engine as the prototype, and verified against the experimental data of the spray mixture formation, ignition delay, in-cylinder pressure and pollutant emissions. Then, the engine performance and emissions of both two modes are studied and optimized. The results show that under the diesel replacement ratio of the commercial methane/diesel dual-fuel marine engine (i.e. around 98%–99%), both two modes can achieve an indicated thermal efficiency (ITE) of over 50%. At the optimized ammonia premixed combustion point, the ITE is increased by 5.1% owing to the significantly reduced cooling loss, but at the expense of 140.6% higher NOx emissions compared to the diesel-only mode. The optimized ammonia high-pressure spray combustion point can achieve a similar ITE and reduce the NOx emissions by around 47% compared to the diesel-only mode. For both the optimum points, the GHG emissions (i.e. CO2 + 300 × N2O) are reduced by around 97%, while the unburned NH3 emissions are negligibly small.

Enhanced virulence of Beauveria bassiana against Thrips tabaci by the addition of bacterial metabolites derived from Xenorhabdus hominickii

• Immunosuppressive agents are supposed to enhance the virulence of microbial pathogens against insect pests. • The culture broth of Xenorhabdus hominickii inhibited immune responses of Thrips tabaci . • The addition of the bacterial broth to Beauveria bassiana enhanced the fungal insecticidal activity. Xenorhabdus and Photorhabdus are two bacterial genera specifically symbiotic to Steinernema and Heterorhabditis , which are the entomopathogenic nematode genera, respectively. These bacteria are well known to produce potent secondary metabolites suppressing insect immune responses. This study aimed to develop a potent microbial insecticide against the onion thrips, Thrips tabaci , using the bacterial metabolites. Among the chemical insecticides that have been used to control the thrips, spinosad was highly effective against both larvae and adults of T. tabaci . Three different entomopathogenic fungi were also effective to kill the thrips. However, the fungal virulence was much less than the control efficacy of the chemical insecticide, spinosad. To enhance the fungal virulence of Beauveria bassiana (Bb), the bacterial culture broth of Xenorhabdus / Photorhabdus was added to suppress the thrips immune defense. Among six different bacterial species, X. hominickii (Xh) produced highly potent metabolites to enhance the fungal virulence. Indeed, four different bacterial metabolites (GameXPeptide, benzylideneacetone, oxindole, and 3-ethoxy-4-methoxyphenol) of the bacteria suppressed the gene expressions of an antimicrobial peptide, lysozyme , which was highly inducible to the fungal infection. To optimize the mixture ratio of fungal and bacterial pathogens, the fungal conidia and bacterial culture broth were freeze-dried and mixed in different ratios. Laboratory and field assays showed that a mixture spray of freeze-dried Xh culture broth (3 g) and Bb conidia (1.17 × 10 9 conidia) in a liter was effective to control T. tabaci infesting welsh onion.

Impact of volatility reduction agents on dicamba and glyphosate spray solution pH, droplet dynamics, and weed control.

Regulations in 2021 required the addition of a volatility reduction agent (VRA) to dicamba spray mixtures for postemergence weed control. Understanding the impact of VRAs on weed control, droplet dynamics, and spray pH is essential. Adding glyphosate to dicamba decreased the solution pH by 0.63 to 1.85 units. Across locations, potassium carbonate increased the tank-mixture pH by 0.85 to 1.65 units while potassium acetate raised the pH by 0.46 to 0.53 units. Glyphosate and dicamba in tank-mixture reduced Palmer amaranth control by 14 percentage points compared to dicamba alone and decreased barnyardgrass control by 12 percentage points compared to glyphosate alone 4 weeks after application (WAA). VRAs resulted in a 5-percentage point reduction in barnyardgrass control 4 WAA. Common ragweed, common lambsquarters, and giant ragweed control were unaffected by herbicide solution 4 WAA. Dicamba alone produced a larger average droplet size and had the fewest driftable fines (% volume < 200 μm). Potassium acetate produced a larger droplet size than potassium carbonate for Dv0.1 and Dv0.5 . The addition of glyphosate to dicamba decreased droplet size from the entire spray droplet spectrum (Dv0.1 , Dv0.5 , Dv0.9 ). A reduction in spray pH, droplet size, and weed control was observed from mixing dicamba and glyphosate. It may be advisable to avoid tank-mixtures of these herbicides and instead, apply them sequentially to maximize effectiveness. VRAs differed in their impacts on spray solution pH and droplet dynamics, but resulted in a minimal negative to no impact on weed control. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Efficiency of the autonomous modular system in the implementation of the spray application process in the vineyard

Autonomous modular system mounted on a conventional (CON) sprayer operating on the principle of pulse-width modulation (PWM) control of electromagnetic valves represents state-of-the-art technology for implementation controlled application of spray mixture without changing the operating parameters of the sprayer (e.g. spray pressure, nozzle size). In accordance with the principles of precision viticulture, the pulse width modulation control is the primary technology, which allows the application of the required amount of spray mixture exclusively to the target areas of the vine without changing the droplet size spectrum and allows for even deposit quality and reducing the drift outside the target areas. In the vineyard, we tested an autonomous axial sprayer prototype throughout the entire spraying season in 2021 on which we have installed an autonomous modular system with enabled pulse-width control. We tested two modes of operation of the sprayer prototype, namely autonomous (continuous duty cycle control (DC: 0 to 100%)) and conventional (nozzle fully open at all time), at a steady spray speed of 6 kmh-1. We compared the amount of PPP expressed as a percentage between autonomous and conventional mode of operation of the sprayer through individual nozzles on the sprayer. The maximum saving of the spray mixture of 69.8%, through an individual nozzle was measured at phenological stage of the vine BBCH 55. A comparative analysis between the CON and PWM mode of the spray mixture application showed that we saved 626.24 l per year in the automated mode of operation.

Effects of Low Pressure Injection on Fuel Atomization and Mixture Formation for Heavy Fuel Engines

The application of direct injection (DI) technology can effectively improve the atomization effect of heavy fuel to reduce the fuel loss of heavy fuel engines (HFE). The fuel spray characteristics directly affect the combustion performance of the engine. To investigate the atomization process and evaporation characteristics of heavy fuel in-cylinder for an air-assisted direct injection (AADI) engine, a simulation calculation model of AADI HFE was established with the use of a computational fluid dynamics tool. The air-assisted injector model and the one-dimensional performance calculation model were verified by test data. The influences of injection timing and injection pressure on the spray characteristics and mixture formation in the engine cylinder were discussed. The results show that the mixture concentration distribution is uniform after the injection timing is advanced, and the mass fraction of the fuel evaporation increases. The earlier injection timing can provide the fuel with sufficient time to evaporate, while the later injection timing will result in increasing the Sauter mean diameter (SMD) of the fuel droplets, and the unevaporated heavy fuel in the combustion chamber tends to become concentrated. With the increase in air injection pressure, the distribution of the mixed gas in the cylinder becomes uniform, and the SMD of the fuel droplets in the cylinder decreases. When the injection pressure is 0.65 MPa and 0.75 MPa, the difference between the SMD of the fuel droplets in-cylinder decreases, and a favorable fuel atomization effect can be maintained.

Characterization of ammonia spray combustion and mixture formation under high-pressure, direct injection conditions

Ammonia has the potential to replace fossil fuels in internal combustion engines (ICEs). However, ammonia is characterized by unfavorable combustion characteristics and a propensity to form pollutants during combustion. The pilot-ignited high pressure, direct-injection of ammonia is promising regarding its prospective performance with ammonia as fuel. In this work, optical investigations (Mie-scattering (MS), shadowgraphy (SG), OH* chemiluminescence (CL)) and heat release rate (HRR) analysis are complemented by 1-D spray modeling to provide fundamental insight into distinctive features of ammonia spray combustion and mixture formation under engine-relevant conditions in a rapid-compression-expansion-machine (RCEM). CL measurements reveal that ammonia spray flames do not stabilize after ignition by a diesel pilot injection. Instead, the lift-off length gradually increases until the end of injection and beyond. To aid in the interpretation of the lift-off behavior, a 1-D, mixing-limited spray model is validated by experimental results for ammonia spray penetration and stationary liquid length (LL) under non-reactive conditions. Modeling results reveal that ammonia sprays are marked by low temperatures close to the nozzle exit, followed by a rapid decrease in mean equivalence ratios well below 1. Based on a mechanism that suggests flame stabilization by product re-entrainment and subsequent auto-ignition, the inhibition of flame stabilization in ammonia sprays is explained by high mixing requirements with combustion products to undergo auto-ignition. Implications of the lack of a self-stabilized flame on combustion characteristics are discussed and diesel post-injections, fuel pre-heating and reduction of the natural lift-off length are suggested as measures to avoid extensive pollutant formation in regions upstream of the lift-off length after the end of ammonia injection.

Numerical modeling of diesel and polyoxymethylene dimethyl ether spray in a high pressure chamber using the fischer primary breakup model

In the strive for the climate-neutral and ultra-low emission vehicle powertrains of the future, synthetic fuels produced from renewable sources will play a major role. Polyoxymethylene dimethyl ethers (POMDME or “OME”) produced from renewable hydrogen are a very promising candidate for zero-impact emissions in future CI engines. To optimize the utilisation of these fuels in terms of efficiency, performance and emissions, it is not only necessary to adapt the combustion parameters, but especially to optimize the injection and mixture formation process. In the present work, the spray break-up behavior and mixture formation of OME fuel is investigated numerically in 3D CFD and validated against experimental data from optical measurements in a high pressure/high temperature chamber using Schlieren and Mie scattering. For comparison, the same operating points using conventional diesel fuel were measured in the optical chamber, and the CFD modeling was optimized based on these data. To model the spray-breakup phenomena reliably, the primary break-up model according to Fischer is used, taking into account the nozzle internal flow in a detailed calculation of the disperse droplet phase. As OME has not yet been investigated very intensively with respect to its chemico-physical properties, chemical analyses of the substance properties were carried out to capture the most important parameters correctly in the simulation. With this approach, the results of the optical spray measurement could be reproduced well by the numerical model for the cases studied here, laying the basis for further numerical studies of OME sprays, including real engine operation.

Health, Pesticide Adjuvants, and Inert Ingredients: California Case Study Illustrates Need for Data Access.

Background:Many pesticide products are mixtures of multiple chemicals. These include active ingredients intended to kill pests, and so-called inert ingredients intended to improve the physical characteristics of the product. In addition, shortly before applying a pesticide product, applicators often mix adjuvants into the sprayer tank. Adjuvants are products designed to improve the performance or physical properties of a pesticide spray mixture. Manufacturers may use a particular chemical compound both as an inert ingredient within pesticide products and as a component of adjuvant products. Nonetheless, regulations dictate that data on use are publicly available only for the portion used in adjuvants. Adjuvants are exempt from federal registration, but are defined as pesticides in California. Based on that definition, California has identified -hydroxypoly(oxyethylene) (APNOHO) as the most widely used pesticide in the state, applied to more than acres annually. That quantified use includes only agricultural acres treated with adjuvants containing APNOHO. Total APNOHO use is likely higher because manufacturers also use the chemical as an inert ingredient within pesticide products, although data on such use are shielded by regulation.Objectives:We use APNOHO as a case study to demonstrate that the use of adjuvants and inert ingredients is difficult to track because relevant information is not publicly available. We synthesize information that suggests widespread agricultural use of alkylphenol ethoxylates, such as APNOHO, may pose significant human and environmental health risks. We then make recommendations for future research and policy.Methods:We used information from California’s pesticide use reporting system and the U.S. Environmental Protection Agency (EPA) to estimate use of APNOHO. We used U.S. EPA and European databases, as well as published research, to identify human and environmental health hazards of APNOHO. We focused on research showing that APNOHO is an endocrine-disrupting chemical.Discussion:Within California, APNOHO is applied in more than 150 adjuvant products. Nationwide, it is used as an inert ingredient in at least 650 pesticide products. Exposure to APNOHO is associated with endocrine disruption, birth defects, and aquatic toxicity. We suggest that the case of APNOHO illustrates the larger problem of a lack of publicly available data on use and toxicity of many adjuvants and pesticide inert ingredients. We recommend that researchers and regulators include adjuvants and inert ingredients when evaluating pesticide hazards, including endocrine disruption. We also recommend regulatory requirements to identify all ingredients on product labels. https://doi.org/10.1289/EHP10634

Climate nutrient management for various sources and levels of fertilizers on soil nutrients, growth and yield of maize (Zea mays l.) in Madurai district, Tamil Nadu, India

Global climate change is expected to soil processes and properties, which are important for restoring soil fertility and low productivity. The field experiment was conducted at Research Farm, Agricultural College, and Research Institute, Madurai district, Tamil Nadu, during Kharif season 2021 to study of various sources and fertilizers' levels to influence under deficit and excess water conditions on soil fertility, growth, and yield of maize (Zea mays). The study revealed that excess and deficit water condition in moisture regime irrigations at Irrigation water / Cumulative Pan Evaporation (IW/CPE) ratio of 1.0 along with nutrient management practices (N8) 125 % Soil Test Crop Response (STCR) - NPK soil application by 1 % foliar spray of micronutrient mixture. Significantly higher of mean values available nitrogen (225 kg ha-1), available phosphorous (20.81 kg ha-1), available potassium (351 kg ha-1), dry matter production (DMP) (16,404 kg ha-1), plant height (250 cm) and yield (9,030 kg ha-1) and was comparable with IW/CPE ratio of 0.8, 0.6 along with others nutrient management practices at 100 % and 75 % STCR - NPK followed by foliar sprays 2 % NPK (19:19:19) and Pink-pigmented facultative methylotrophs (PPFM) 1 %. Hence, under a normal water availability situation, irrigation at an IW/CPE ratio of 0.8 was good enough to produce a higher yield, while under deficit and excess water conditions IW/CPE ratio of 1.0 along with125 % STCR-NPK by foliar spray of micronutrient mixture of 1 % was suitable for obtaining optimum nutrient management for enhancing soil fertility, growth and yield of maize.

Comparative Efficacy of Superheated Dry Steam Application and Insecticide Spray Against Common Bed Bugs Under Simulated Field Conditions.

The common bed bug, Cimex lectularius L., is a difficult urban pest to control. A simulated field study was conducted to compare the efficacy of steam application and an insecticide mixture spray (0.05% acetamiprid and 0.06% bifenthrin mixture) against C. lectularius. Three types of furniture (desk chair, upholstered armchair, and wooden table) were treated in the laboratory. The efficacy of the treatments was evaluated by visual inspection and placement of interceptor traps under the legs of the furniture. One hundred mixed stages of an insecticide-resistant population of C. lectularius were released onto each furniture item. After a 10-day acclimation period, each furniture item received steam treatment, insecticide spray, or no treatment. The second application of treatment was conducted 14 d later. Bed bug counts from interceptors and visual inspections were recorded at 13 d and 28 d after the initial treatment. At 28 d, the mean (± SE) live bed bug count in the steam, spray, and control group was 1 ± 0, 2 ± 1, and 83 ± 10, respectively. Both treatment methods were highly effective in controlling bed bugs on furniture. The mean bed bug count from interceptors in the steam, spray, and control groups were 0.3 ± 0.2, 11 ± 7, and 47 ± 9, respectively. There was no significant difference in the efficacy between steam and spray treatments based on either visual inspection or bed bug counts from interceptors. However, based on interceptor counts, the steam treatment caused faster bed bug population reduction than insecticide sprays.

Potential effect of wetting agents added to agricultural sprays on the stability of soil aggregates

Abstract. A potential effect of adjuvants/wetting agents added to the spray mixture on the water stability of soil aggregates (WSA) in agricultural soil was studied. Nine sites were chosen in the Czech Republic. Each site was mapped using representative soil pits (depth min. 1.3 m). A total of 54 mixed samples were collected from topsoil horizons on the selected sites. The samples were exposed to the action of four different types of wetting agents (organosilicone wetting agent; methyl ester of rapeseed oil; mixture of methyl ester palmitic and oleic acids; isodecyl alcohol ethoxylate), which are the most common wetting agents used in agriculture in the Czech Republic. WSA was determined before and after the addition of wetting agents (WA). Initial WSA values were at the same level in a majority of sampling points. Two sites were an exception, on which Haplic Luvisols and Relictistagnic Fluvisols occurred. These soil types featured the lowest WSA values. After the addition of WA across the sampling points, average WSA values exhibited a demonstrable trend: WSA of control sample (without the WA application) was at all times higher than in samples with the addition of WA. If the measured WSA values are compared in terms of overall means, it is evident that the control variant always exhibited the highest WSA value (on average 44.04 %) and the variants with the application of WA showed always WSA values lower by min. 16 %. The worst effect on WSA was that of wetting agents whose basic component was methyl ester of rapeseed. These wetting agents caused a decrease in WSA by more than 50 %. All soil samples were also analysed for basic soil parameters (glomalin, oxidizable carbon – Cox, pH, Na, P, Ca, K, Mg) in order to determine their potential influence on aggregate stability and to possibly eliminate the negative impact of WA. In this respect, only a significant influence of Cox content on WSA was recorded, which positively correlated with the stability of soil aggregates.

Impact of Frontline Demonstration on Increasing Productivity and Profitability of Rose

Krishi Vigyana Kendra conducted a frontline demonstration on Integrated crop management in Rose during the year 2017-18 in 10 farmers' holdings of Chikkaballapur district. The crop was grown with integrated crop management practices compared with the farmer's practice. The integrated crop management practices were the application of bioagents (Trichoderma &amp; Pseudomonas) enriched FYM to soil, fertigation, foliar spray of micronutrient mixture, timely pruning techniques, use of yellow sticky cards and use of need based plant protection chemicals to manage thrips and powdery mildew incidence. The results of the demonstration indicated that the demonstration of integrated crop management practices recorded a higher rose yield (127.0 q/ha) compared to farmers' practice (114.0 q/ha). The increase in yield under demonstration over farmer's practice was 11.40 %. The thrips infestation (6.94 %) and powdery mildew incidence (11.45 %) were lower in demonstration and higher in farmer's practice (13.60 % and 20.02 %). The front line demonstration plots fetched a higher net income of Rs.1019250/ha as compared to Rs. 828000/ha with farmer's practice. The higher benefit cost ratio (5.06) was realized in demonstration and lower benefit cost ratio (3.65) was realized in farmer's practice.

Potassium carbonate effects on spray mixture pressure changes and final pH

AbstractThis research examined a potential nuisance aspect of the use of the volatility-reducing agent (VRA) potassium carbonate when combined with glyphosate in spray-tank mixtures. A VRA is now required to be added to dicamba applications to reduce off-target movement from volatility. When no VRA potassium carbonate was added to the spray mixture, there was no pressure buildup. The addition of VRA potassium carbonate plus glyphosate (which lowers the pH) resulted in an observed pressure buildup. Although the gas produced was not identified, it would be expected to be carbon dioxide formed by the dissolution of the carbonate anion from the VRA. Source water pH range from 3.2 to 8.2 had no effect on pressure buildup. Pressure buildup was directly related to water temperature, with a linear response to temperature when the VRA was added last; in contrast, a less direct relationship of temperature to pressure buildup existed at temperatures &gt;30 C when the VRA potassium carbonate was added first. There was no effect on the pressure increase from adding a defoamer or a drift control agent.

Gap optimization of electrostatic aerial spray nozzles for low-speed aircraft

The gap between the spray plume and the cylindrical charging electrode for an aerial electrostatic spray nozzle is critical to achieve maximum chargeability of spray formulations prior to aerial applications of pest control products. Seven discrete gaps from the nozzle tip to the trailing edge of the electrode were tested for spray chargeability. A spray mixture of tap water and a non-ionic surfactant with an electrical conductivity of 1012.75 ± 6.70 μS was atomized through three different-sized nozzle tips (TXVK-3, TXVK-4, and TXVK-6) in a controlled high-speed wind tunnel operated at 6 different airspeeds between 80 and 177 km/h with two atomizing air pressures, 310 and 517 kPa, representing minimum and maximum values commonly used in rotary wing agricultural aircraft. The TXVK-3 nozzle yielded significantly higher charge-to-mass ratio (Q/M > 1.0 mC kg-1) compared to the TXVK-4 and TXVK-6 nozzles. At 310 kPa liquid pressure, the 6.5- and 9.3-mm gaps produced significantly higher spray charge. Data indicated that the chargeability of aerial electrostatic sprays can be improved using a smaller orifice and lower flow rate nozzle operated at a lower liquid pressure and higher airspeed. Results from this study may help aerial applicators better understand the optimum operational parameters required to maximize the electrostatic charge of spray formulations while flying low speed aircraft.

Industrial treatment of soybean seeds subjected to high volumes of fungicides, insecticides, biostimulants and micronutrients during storage

The objective of this study was to examine the performance of soybean seeds at different storage periods as well as their physiological quality after the application of spray mixtures of insecticides, fungicides, polymers, micronutrients and biostimulants. The experiment was laid out in a completely randomized design with four replicates. Treatments were as follows: T1 - untreated seeds (control); T2 - insecticide and fungicide + polymer + drying powder; T3 - insecticide and fungicide + polymer + drying powder + micronutrient; and T4 - insecticide and fungicide + polymer + drying powder + micronutrient + biostimulant. For each industrial seed treatment (IST), the specific spray volumes tested were 0, 400, 600 or 1100 mL 100 kg seeds-1. Soybean seeds were stored for 0, 15, 30, 45, 60 and 90 days and subsequently evaluated for physiological potential. At each storage period, the following tests were conducted: germination, first count, accelerated aging, emergence speed index, final emergence in sand substrate, whole-seedling length, shoot length and root length. Industrial seed treatment reduces seed physiological quality. The seed treatment corresponding to the highest spray volume provided the lowest means in all tested treatments. For all analyzed variables, the ST4 treatment, to which biostimulant was added, presented the lowest averages, indicating that the greater the volume of spray, the greater the damage caused to the physiological quality of the seeds, both before and after storage