|Ozkan, H - OSU|
|Guler, H - OSU|
Submitted to: ASABE Annual International Meeting
Publication Type: Proceedings
Publication Acceptance Date: March 20, 2006
Publication Date: July 12, 2006
Citation: Zhu, H., Derksen, R.C., Ozkan, H.E., Guler, H., Brazee, R.D., Reding, M.E., Krause, C.R. 2006. Development of a Canopy Opener to Increase Spray Deposition and Coverage inside Soybean Canopies [abstract]. ASABE Annual International Meeting. Paper No. 061164. Technical Abstract: At the growth stage from R3 to R5, the foliage at the top of a soybean canopy takes the most part of the canopy and these top leaves cover the most area of the field. Because of the high foliage density at the top of canopy, conventional boom sprayers can hardly deliver sufficient chemical droplets to inner part of canopies. An experimental canopy opener was developed and attached on a conventional boom sprayer to increase spray deposition inside soybean canopies. The canopy opener consisted of a conduit pipe mounted on the spray boom upwind the nozzles. The conduit pipe opened the top part of canopies as the sprayer traveled to achieve better penetration of spray into lower parts of the soybean plant, where the rust infection first starts. Conventional flat fan nozzles were used for the test with the canopy opener for the application rate of 145 L/ha. Spray deposition and coverage at two heights inside canopies were determined. Treatments included three depths of the opener inside canopies, three horizontal distances of the opener from nozzles, and two nozzle sizes. A mathematical model was also developed to determine the distance between the opener and nozzles so that droplets could be delivered inside canopies before the top part of canopy returning to vertical positions. Spray deposition and coverage inside canopies with the opener were also compared with an air assisted sprayer and a conventional boom sprayer with different hydraulic nozzles. With the help of the canopy opener to push the top part of canopies, spray droplets had more space to reach middle and bottom of canopies, resulting in higher spray deposition and coverage on targets inside canopies.