Feasibility of a Solid set canopy delivery system for efficient agrochemical delivery in vertical shoot position trained vineyards

Solid set canopy delivery systems (SSCDS) offer advantages such as reduced off–target drift and human exposure to chemicals compared to conventional axial–fan airblast sprayers. In this study, six different SSCDS configurations (C1–C6) with two different emitter types (E1 and E2) were installed in a vertical shoot position (VSP) trained grapevine and evaluated for spray deposition and coverage during early, mid, and late growth stages. Emitters E1 and E2 had full–circle and hollow–cone spray pattern, respectively. Configuration C1 had a pair of E1 emitters installed per vine at 760 mm above the cordon. Configurations C2 and C3 had 2 pairs of emitters (E2 and E1, respectively) installed per vine near the cordon and C4 was a combination of C1 and a pair of E2 emitters at the cordon. Configurations C5 and C6 had two E2 emitters per vine installed near the drip line, and C5 also had E1 emitters 760 mm above the cordon. Overall, configurations with emitters installed close to both the top and bottom canopy zones (i.e., C1, C4 and C5) provided the best coverage and deposition in a VSP trained vineyard. Deposition for C1, C4 and C5 was 588 ± 159 ng cm −2 (mean ± std. error), 653 ± 123 ng cm −2 and 607 ± 114 ng cm −2 , respectively. Coverage for respective configurations was 19 ± 4%, 23 ± 4% and 25 ± 4%. Overall, deposition did not differ significantly between upper–and under–sides of leaves whereas deposition and coverage in the top and bottom zones differed significantly among different configurations.