The Effect of Application Volume and Deposition Aids on Droplet Spectrum and Deposition in Broccoli for Aerial Applications

A field study was conducted to determine the influence of application volume and tank mix deposition aids on coverage in broccoli for a fixed wing aerial application. The study involved using a turbine powered aircraft to apply five products designed to improve deposition in 28, 47, and 94 l/ha tank mix solutions. Kromekote papers were used to collect the data at low and medium positions in full canopied broccoli plants. Comparisons between treatments using Dropletscan™ software to calculate droplet statistics, deposition (percent area coverage), and number of droplets per cm 2 in the lower and middle portions of the canopy are reported. Differences in coverage were found between the product and volume treatments compared with very few being significant. The higher application volumes resulted in higher coverage's for all products tested with the 94 l/ha providing significantly more coverage. The addition of the deposition aids improved the coverage within the 28 and 47 l/ha comparisons with the combination treatment of Interlock and Preference resulting in the highest amount of coverage in the lower canopy. In the 94 l/ha comparisons, the water and prime oil provided more coverage than a combination of Interlock and Preference which were both significantly better than a combination of Interlock and Rivet. Higher application volumes resulted in an increased number of droplets in the lower canopy. The combinations of Interlock and Rivet and Interlock and AG 06038 improved the droplet counts. Droplet size was slightly affected by the different tank mix products. The trend was for the higher application volume treatments to show increased droplet sizes.