W pracy przedstawiono model empiryczny współczynnika zmienności oprysku dla rozpylaczy szczelinowych w zależności od wysokości i kąta ustawienia belki polowej oraz ciśnienia cieczy. Stwierdzono, że najkorzystniejsze warunki pracy ze względu na najniższą wartość współczynnika zmienności poprzecznej oprysku obserwowano dla ustawienia belki polowej na wysokości 0,6-0,7 m przy jej poziomym położeniu i ciśnieniu cieczy w zakresie 0,25-0,30 MPa.
Two field studies (I and II) at the University of Nebraska-Lincoln: John Seaton Anderson Turfgrass Research Facility near Mead, NE, USA, were conducted to determine if a new ultra-low volume (ULV) sprayer can apply foliar nutrient, growth regulator, and fungicide treatments, in a manner similar to that of a conventional sprayer. Treatments were applied over creeping bentgrass ‘L-93’ (Agrostis stolonifera L.) managed as a fairway at 561 l · ha−1 and 47 l · ha−1 with the conventional and ULV sprayer, respectfully. Data were collected for chlorophyll content with a chlorophyll meter, and for the normalised difference vegetation index (NDVI) with a turf colour meter. Each plot was harvested for biomass at 21 days after treatment. Study II compared the ULV sprayer and a conventional sprayer, for the control of brown patch (Rhizoctonia solani Kuhn) in creeping bentgrass. The treatments were propiconazole and azoxystrobin. Spray volume was 561 l · ha−1 for the conventional sprayer, and 19 l · ha−1 for the ULV sprayer. Statistical differences in turf quality or dry weight reductions between the conventional and ULV sprayer were not detected. Brown patch control was also similar between the two sprayers, but azoxystrobin provided better control than propiconazole. Even with a 30-fold decrease in application volume, the results indicated that the Kamterter ULV sprayer may be a useful and effective management option for foliar fertiliser and fungicide applications in turfgrass.
Background. Faulty but still operating agricultural pesticide sprayers may pose an unacceptable health risk for operators. The computerized models designed to calculate exposure and risk for pesticide sprayers used as an aid in the evaluation and further authorisation of plant protection products may be applied also to assess a health risk for operators when faulty sprayers are used. Obj ective. To evaluate the impact of different exposure scenarios on the health risk for the operators using faulty agricultural spraying equipment by means of computer modelling. Material and methods. The exposure modelling was performed for 15 pesticides (5 insecticides, 7 fungicides and 3 herbicides). The critical parameter, i.e. toxicological end-point, on which the risk assessment was based was the no observable adverse effect level (NOAEL). This enabled risk to be estimated under various exposure conditions such as pesticide concentration in the plant protection product and type of the sprayed crop as well as the number of treatments. Computer modelling was based on the UK POEM model including determination of the acceptable operator exposure level (AOEL). Thus the degree of operator exposure could be defined during pesticide treatment whether or not personal protection equipment had been employed by individuals. Data used for computer modelling was obtained from simulated, pesticide substitute treatments using variously damaged knapsack sprayers. These substitute preparations consisted of markers that allowed computer simulations to be made, analogous to real-life exposure situations, in a dose dependent fashion. Exposures were estimated according to operator dosimetry exposure under ‘field’ conditions for low level, medium and high target field crops. Results. The exposure modelling in the high target field crops demonstrated exceedance of the AOEL in all simulated treatment cases (100%) using damaged sprayers irrespective of the type of damage or if individual protective measures had been adopted or not. For low level and medium field crops exceedances ranged between 40 - 80% cases. Conclusions. The computer modelling may be considered as an practical tool for the hazard assessment when the faulty agricultural sprayers are used. It also may be applied for programming the quality checks and maintenance systems of this equipment.
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