Optimization of spray application technology in ornamental crops

Main research question/goal

Greenhouse growers predominantly use handheld sprayers instead of spray boom equipment for their plant protection needs. These handheld sprayers have several drawbacks in comparison to spray booms, including higher exposure risks for the operator and the environment as well as less uniform spray results and higher labour costs.

For these reasons, growers need information about more efficient application techniques such as spray boom equipment. This study answers their questions: What is the correct way to use spray boom systems? What is their efficiency? What about spray pressure and volume? What are the risks for worker and environmental exposure? How uniform is the spray deposition on the crop?

Research approach

We perform deposition trials using different spray application techniques on various ornamental crops and vegetables grown in greenhouses as well as in laboratory and field trials. We compare traditional handheld techniques with horizontal and vertical spray boom prototypes. For the spray boom systems, we study the (combined) effect of nozzle type, spray pressure, droplet characteristics, spray angle, spray volume and air support on spray deposition and penetration.

Relevance/Valorisation

This study shows that spray booms generally provide more uniform coverage and higher deposition rates than the traditional handheld techniques. Using a spray boom reduces the spray volumes and minimizes losses to the environment and worker exposure. Spray boom systems also improve the bio-efficacy and the sustainable use of the plant protection products. In addition, these research results can be used to convince even more growers of the many advantages of spray boom systems. Several easily adjustable, manually operated spray boom prototypes have been built at ILVO.