Submitted to: Greenhouse Product News
Publication Type: Other
Publication Acceptance Date: August 1, 2001
Publication Date: N/A
Technical Abstract: A varieties of methods are used to treat greenhouse crops with pesticides, including hand-held and stationary whole-room sprayers. Few recommendations are available to help greenhouse producers understand how to best use their equipment and contain costs. Preliminary experiments conducted by ATRU scientists set to define the deposition characteristics of two, hand-held greenhouse sprayers and one whole-room fogger. Experiments were conducted in a commercial production facility with poinsettia or fuchsia plants located on benches and in overhead baskets. A tank mix containing a fluorescent tracer was applied with each sprayer. Following application, image analysis was used to assess spray coverage on leaves taken from different areas of the canopy. Results showed that the stationary, whole-room fogger produced very consistent coverage throughout the greenhouse with the smallest droplet deposits on adaxial and abaxial leaf surfaces. However, coverage was lower for the whole-room fogger than for the hand-held sprayers. The electrostatic sprayer produced the highest coverage on all leaf surfaces. The tests also indicated that spray coverage could be improved by decreasing the nozzle to target distance and taking a little more time to made applications. Additional application issues such as pesticide dose must be considered to effectively match the equipment to the pest control needs. These studies provide some indication that different application techniques may affect pesticide performance differently. Results will help guide greenhouse producers in their decisions on what equipment to use for most effective pest control.