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.

BackgroundPesticide spray drift, which is the movement of pesticide by wind to any location other than the intended area, is hazardous to human, animal, food safety and environmental health. It is not possible to completely eliminate spray drift during spraying with field crop sprayers, but spray drift can be reduced by developing new technologies. The most common methods to reduce spray drift are carrying the droplets to the target with air‐assisted spraying, electrostatic spraying, preferring air induction nozzles and boom shields. With these methods, it is not possible to make a change on the sprayer depending on the wind intensity during spraying. In this study, a novel servo‐controlled spraying system was designed and developed to change the nozzle orientation angle in the reverse direction of the wind current to reduce the ground spray drift in real time and automatically in a wind tunnel. The displacement in the spray pattern (Dc) was used as a ground drift indicator for each nozzle to evaluate the spray drift.ResultsThe developed system, operated by LabVIEW software, calculated different nozzle orientation angles depending on nozzle types, wind velocities and spraying pressures. Orientation angles calculated for different test conditions achieved in reduction were up to 49.01% for XR11002 nozzle, 32.82% for AIXR11002 nozzle and 32.31% for TTJ6011002 nozzle at 400 kPa spray pressure and 2.5 m s−1 wind velocity.ConclusionThe developed system, which has a self‐decision mechanism, calculated the nozzle orientation angle instantaneously according to the wind velocity. It has been observed that the adjustable spraying nozzle system, sprayed with high precision towards the wind in the wind tunnel, and the developed system have advantages compared to conventional spraying systems. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

ÖzTürkiye de yılda ortalama 40-45 bin ton tarım ilacı kullanılmaktadır. Bu ilaçların önemli bir miktarı yabancı otlarla mücadelede kullanılmaktadır. Ancak son yıllarda kimyasal mücadele maliyetlerinin artışı, herbisitlerin insan ve çevreye olan olumsuz etkilerinin kavranması, organik ve tıbbi bitki tarımının önem kazanması ve ayrıca her yıl herbisitlere dayanıklılık kazanan yabancı ot tür sayısının artması, dünya bilim adamlarını herbisite alternatif olabilecek yöntemlerin araştırılmasına itmiştir. Yabancı otlarla mücadelede herbisitler dışında en ümit var yöntemler, termal yöntemler olarak görünmektedir. Çünkü bu yöntemler, kontrollü uygulandığında çevreye yaydıkları emisyonlar çevre açısından bir risk taşımamaktadır. En yaygın olarak araştırmalara konu olan termal yöntemler; alevle, sıcak su, buhar ve yeni bir teknik olan infrared ışınımla yabancı otların kontrolünden oluşmaktadır. Ancak bu yöntemlerin en önemli sorunlarından bazıları, sistemlerin işletilmesindeki yüksek yakıt maliyetleri, farklı ot çeşitlerine göre değişen etkinlik, alevle mücadeledeki yangın riski ve yüksek ısı nedeniyle kültür bitkisi dokularına verilen zarardan oluşmaktadır.Bu çalışmada, kimyasal olmayan bazı yabancı ot kontrol yöntemlerine yer verilmiştir.Anahtar Kelimeler: Termal yöntemler, alevle ot kontrolü, sıcak su uygulama, buharla ot kontrolü, infrared ışınımla ot kontolü AbstractPesticide consumption is about 40 to 45 tons per year in Turkey and a valuable amount of this consumption is consisted of herbicides which are used in weed control. But, due to increasing of pesticide cost, concerns about pesticides' risks on environment and human life, increasing interest to organic farming and medical plants, increasing the resistance of some weed sorts to herbicides, scientists have trended to find new alternatives to the herbicides. Besides of herbicides, the most preferable methods seem to be thermal methods. Because, the emissions of these methods don't include any environmental risks if these methods were operated in an appropriate situation. The common thermal methods which are subjected to researches are flaming, hot water, steam and infrared heater that is known a new technology in weed control. However, the some concerns and problems regarding with these thermal methods consist of high fuel expenses, variable effects depending on the weed sorts, fire risks in flaming and potential head risk on cultivated plants' tissue injuries. In this paper, some thermal weed control methods were given and discussed.