Greenhouse Evaluation of Air-Assisted Delivery Parameters for Mature Poinsettias

Please use this identifier to cite or link to this item:

Show full item record

Files Size Format View
fac_CanasLA_App ... nAgriculture_2010_26_6.pdf 1.770Mb PDF View/Open

Title: Greenhouse Evaluation of Air-Assisted Delivery Parameters for Mature Poinsettias
Creators: Derksen, R. C.; Ranger, C. M.; Canas, L. A.; Zhu, H.; Krause, C. R.
Issue Date: 2010-11
Publisher: American Society of Agricultural and Biological Engineers
Citation: R. C. Derksen et al, "Greenhouse Evaluation of Air-Assisted Delivery Parameters for Mature Poinsettias," Applied Engineering in Agriculture 26, no. 6 (2010)
Abstract: Understanding the performance characteristics of application equipment is important for helping make the most efficacious applications. While handguns making high volume applications are common in greenhouse production, it is difficult to achieve uniform distribution of product in a timely manner. Broadcast applications made using air-assistance can help aid canopy penetration and the volume of carrier required to make applications. The objectives of this research were to determine how air-assist sprayer application parameters influence spray deposits on the undersides of leaves in a mature poinsettia canopy. Bench-top trials were conducted using a motorized boom inside a greenhouse to treat a mature and dense poinsettia canopy. Sprayer treatments applied a tank mix of water and fluorescent tracer. Nylon screen targets were secured to the underside surfaces of leaves in the upper and lower elevation of target plants. A five-port, air-assist nozzle with flat fan nozzle tips was used to make the applications. Three air outlet speeds, two travel speeds, and three nozzle flow rates were evaluated. Each treatment was replicated three times. Spray deposits were highly variable. Upper elevation spray deposits were significantly greater than lower elevation deposits. Individually, higher air outlet speed (36.0 m s(-1)), slower travel speed (3.2 km h(-1)), and higher nozzle flow rate (1.17 L min(-1)) tended to produce higher sprayer deposits on the underside surfaces of leaves. The combination of travel speed and nozzle flow rate that produced the highest application rate (900 L ha(-1)) also produced the highest deposits. There was a 500% increase in underside leaf surface deposits in the lower canopy area for a corresponding 500% increase in application rate. However, the main effects produced no significant differences in spray deposits in the lower canopy area. Further improvements in directing sprays or providing canopy turbulence are necessary to improve deposition and management of insect pests feeding on the underside of poinsettia leaves.
ISSN: 0883-8542
Bookmark and Share