When pesticides are sprayed, a significant portion of the droplets drifts away from the target. Using an adjuvant in spray liquid is an easy option for reducing droplet drift because there is no need to make any changes to the sprayer. The objective of the study was to determine the effects of seven commercially available adjuvants (Surfeco plus, Starguar, Kantor, Sterling, Control, Control WM, and Control DUO) with varying active ingredients on droplet size, surface tension, and viscosity. Since these properties affect droplet formation, these adjuvants were evaluated in terms of their drift-reducing performance in a wind tunnel at various wind speeds (2.0, 3.5, and 5.0 m/s) and spray pressures (3, 4, and 5 bars). The ground and airborne components of drift were evaluated. With the use of a patternator, the potential for the ground drift of adjuvants was measured; for airborne drift, polyethylene lines that were stretched along the cross-section area of the wind tunnel at various heights were employed. The number of deposits of a tracer dye–adjuvant mixture that was sprayed on the polyethylene lines was measured via fluorometric methods for determining the airborne drift potential. The test results showed that the adjuvant Control Duo containing a polymer blend, which had the highest dynamic viscosity (4.27 mPa.s), increased the Dv0.5 droplet diameter up to 192 μm at 3 bar with nozzle XR11002. This adjuvant reduced the ground drift potential (Dc) by 60.53 % compared to tap water. The maximum airborne drift potential reduction percentage (DPRP) was obtained as 85.76% with Surfeco plus containing organic silicone at a pressure of 3 bar and a wind velocity of 5 m/s. When considering the airborne drift-reduction potential of the adjuvants used, it was found that the adjuvants Control WM, Control, Starguar, and Surfeco plus significantly reduced the airborne droplet drift compared to spraying tap water.

The efficiency expected from any pesticide depends largely on the type of plant protection machine used in spraying and the operating parameters of the selected machine. Today, sprayers with different spraying wing width are widely used in field spraying. Especially with field sprayers with large working widths, it is difficult to work at high spraying speeds due to the wing width and wing weight. In this study, wingless field sprayer effectiveness was evaluated. Occasionally for spraying instead of sprayers with standard type field spraying booms, the field sprayers with commercial name Electropar, which are operated with high pressure and with oscillating nozzles are used. Since the sprayer has no wings, it can spray at high tractor speeds. optimum working width of this sprayer, pestisit distribution uniformity on a horizontal surface, etc. Its parameters are unknown. In this study, the optimum working width provided by the sprayer at different operating pressures and nozzle oscillation rates, and volumetric fluid distribution throughout the working width and optimum working parameters were determined. The three different working pressures (1, 2 and 3 MPa) and the transverse volumetric fluid distribution of the three jet nozzle units moving in opposite directions relative to each other on a horizontal ground at two oscillations (44 and 60 rpm) were determined by a portable patternator. Operation of the high-pressure cone jet nozzle unit at 1 MPa pressure and 60 rpm oscillating speeds provided a more uniform transverse distribution than other operating parameters. The increase in operating pressure caused an increase in the volume of fluid accumulated in the patternator's grooves at the same working height and sampling distance. The optimum working width, depending on the operating conditions specified by the boomless sprayer, varied between 11.20 and 12.80 m depending on the spray unit oscillating speed and spray pressure.

The first operation of adsorption on leaf surfaces in pulverization is drop sticking. In the water wettability of the surfaces, the sticking of the drops has a great importance. Drop contact angle, contact height, and contact diameter values in the third and tenth seconds were measured with Drop Shape Analysis 10 device to determine adsorption, spreading, and sticking levels by applying mixtures of ten surface active substances including different contents with pure water to different leaf surfaces. The adsorption and sticking rates of the drops they formed on different leaf surfaces were determined for the time they are obtained from the data obtained in both time periods. Furthermore, the spreading rates of the mixtures prepared by taking into account the change rates during the last seven seconds between these two periods were determined as the sticking rate. Coating shares related to covering rates of different surface active substances with different surface properties on the surface of leaves were evaluated as possible work success according to the adsorption, spreading and sticking levels anticipated in spraying. According to their results on the application surfaces, surface active substances and leaves were evaluated statistically by the SPSS 15 program in terms of their similar properties. It has been found that surface active substance mixtures with sodium carboxymethylcellulose and carboxymethylcellulose contents had the largest drop contact angles and contact heights with the smallest drop contact diameters on the leaf surfaces, and a negative impact on the adsorption performance as they spread very little over seven seconds. It has been determined that drops with surface active substance including trisiloxane + allyloxypolyethyleneglycol and alcoholethoxylate, alkylphenolethoxylate have formed the smallest contact angles, minimum drop heights and largest contact diameters on the surface of the leaves, as well as increased adsorption and sticking by spreading rapidly for seven seconds.

No abstract

Surface energy is widely used in the industry to predict behavior of spray droplets on solid surfaces. The targets of pesticide applications which are used extensively in agricultural production are mainly plant leaf surfaces. Digitization of leaf surfaces to estimate the spread and adhesion of a pesticide application is an important approach in providing descriptive information. In this regards, from intensive agricultural products Triticum aestivum L., Citrus sinensis, Fragaria ananassa, Vitis vinifera L., Cucumis sativus, Capsicum annuum L. culture plants, Elymus repens and Sinapis arvensis from weeds were used to determine surface energy. The leaf surface energies were determined by evaluating the contact angles of the drips while obtained from surface tension and its components from known liquids pure water, diiodomethane and formamide liquids on the surface of the leaves according to five different methods. Wu and Equation of State methods have been found to give more accurate results than other methods. Elymus repens and Triticum aestivum L. plants among the statistically three significant grouped leaves were reduce the spreading and sticking of droplets applied on the leaves by providing a more spherical droplet formation. The Fragaria ananassa leaves have encouraged the higher surface energy that they have the spread of the drips on the leaf surface.