The subject of the performed experiments comprised standard RSMM 110-02, RSMM 110-02 nozzles, AI 110-02, AI 110-02 air induction nozzles as well as AZMM 110-02, AZMM 110-03 low drift nozzles. The working speed during spraying was v_p = 7 km/h. Each sprayer was tested at the following three levels of working pressures: p₁ = 0.2 MPa, p₂ = 0.4 MPa and p₃ = 0.6 MPa. The spray liquid was pure water at the temperature of 20°C. The plant coverage was determined: s_k – spray coverage, n_k – number of droplets per 1 cm² of the leaf.

The purpose of applying an additional air flux in field sprayers is limiting liquid drift. The flux also influences the quality of plant spraying. Krukowiak Bravo sprayer, produced by Krukowiak Company, was applied in the research on the influence of air flux on the quality of coverage ofwinter wheat (Sakwa variety). The plant coverage was determined using water sensitive papers. The objective of the experiment was to evaluate the influence of air volume discharged by the air sleeve equipped sprayer and air induction nozzles on the coverage of the plant. The spray coverage ofwheat with ID 120-03 Lechler nozzles was satisfactory, both in case of conventional and air assisted applications.

The influence of different nozzle types and adjuvants on the biological efficacy of fungicides in potato was investigated in four growing seasons in the years 1997-2000. The studied foliar plant disease was late blight (Phytophthora infestans). The biological efficacy of fungicides (alone or with adjuvants) applied with coarse air induction nozzles was comparable to fine standard flat fan nozzle. The differences between the nozzle types tested were small in control oflate blight in potato with systemic and contact fungicides. Coverage of upper side of leaf blades was from three to four times higher than lower side of leaf blades. In general, the highest coverage of upper and lower side of leaf was achieved when the full dosage rate of fungicide (copper oxychloride) was used with both the flat fan XR 110-03 and air induction DB 120-03 nozzle. Adding Atpolan 80 EC and Zero Piany 62 SL to 50% dosage rate of copper oxychloride decreased the spray coverage on lower side ofleaf as well as with both the XR 110-03 and DB 120-03 nozzles. However, addition of adjuvants to spray solution did not decrease the deposition on upper side of leaf blade. In general, adjuvants did not considerably influence the biological efficacy of the fungicide treatments sprayed with both the flat fan and the air induction nozzles but had favourable influence on potato yield.

In greenhouse trials in 1998-1999, the effects of using new spray techniques on the activity of two herbicides for broad-leaved weeds control were examined. Also retention of spray solution containing herbicides with and without addition of oil adjuvant on Chenopodium album and Sinapsis alba leaves was measured. Results showed that air induction and conventional flat fan nozzle gave similar control of tested plants, except Chenopodium album control where fine sprays applied with conventional flat fan nozzle improved efficacy compared with very course spray obtained with air induction nozzle. Also results showed that oil adjuvant addition enhanced biological efficacy for all nozzles, regardless of using herbicide and controlled plant species. Droplet size was the most important factor determining spray retention and activity of herbicides. Efficacy of spray retention depends on the wetting characteristics of the plant, spray application and solution factors.