1. www.ilvo.vlaanderen.be  david.nuyttens@ilvo.vlaanderen.be  +32 9 272 27 82 Comparison between novel and traditional spray application techniques in strawberries  Can spray boom systems improve the spray results in a strawberry crop compared with the traditional spray gun?  What is the effect of nozzle type and setting on spray boom deposition results? D. NUYTTENS, P. BRAEKMAN & D. FOQUE Institute for Agricultural and Fisheries Research (ILVO) – Technology & Food Science Unit – Agricultural Engineering Burg. Van Gansberghelaan 115, bus 1, 9820 Merelbeke (BELGIUM)  Elsanta strawberry crop  Average height ± 0.40 m  Growth stage: end of fruit production  Approx. 8300 running metres ha -1  Canopy spray deposition measurements  Mineral chelates (Fe, Co, Cu, Mn, Mo, Zn; 100 mg L -1 ) Same collectors for the different applications Analysis: Inductively Coupled Plasma (ICP)  Deposition measurements were normalised to a concentration of 100 mg L -1 in the tank and an application rate of 1000 L ha -1 ground surface are expressed as relative values (%) compared to the maximal feasible deposition, assuming a perfectly uniform distribution of the spray liquid on the contours of the crop canopy  Filter paper collectors (7.6 x 2.6 cm²) Three collectors on the crop canopy → spray distribution Two inside the crop → crop penetration Five plants were selected as repetitions Research questions Materials and Methods Results and discussion Reference: Braekman P, Foqué D, Messens W, Van Labeke M-C, Pieters J G, Nuyttens D. 2010. Effect of spray application technique on spray deposition in greenhouse strawberries and tomatoes. Pest Management Science. 66(2): 203-212  Spray application techniques 3-nozzle vertical spray boom Handheld spraygun application VMD: Volume median droplet diameter v vol50 : Average droplet velocity  Deposition (%) on the crop contours for the different techniques  Deposition (%) on the inside of the crop for the different techniques  Deposition (%) on the crop contours for the ≠ collector positions  Deposition (%) on the inside of the crop for the ≠ collector positions Conclusions  (automated) vertical spray booms are a valuable alternative for the traditional spray gun: operator exposure↓, labor-intensity↓, spray deposition and uniformity ↑  Nozzle choice significantly affects spray deposition and penetration  Highest depositions with the air inclusion or extended range flat fan nozzles at their recommended spray pressure  Significant effect of collector position on deposition (2 > 3 > 1)  Important variability of the deposits measured at each sample point  Significant effect of collector position on deposition (4 > 5) → Deeper position in the crop  Important variability of the deposits measured at each sample point  Clear effect of spray system on deposition: boom ~22-60% vs. gun ~20%  Difference most pronounced on top of canopy: boom 13.1% vs. gun 4.5%  Highest deposits with ID 12002, Albuz AVI-Twin 11002 & TeeJet XR 11003, all at their recommended working pressure of 6.0, 6.0 and 2.5 bar  Deposition with gun was only significantly lower than boom for ID 12002 nozzle  Best crop penetration with the ID 12002 nozzle: big and fast droplets  Increasing spray pressure above the recommended one and spray angling did not improve penetration