An Assessment of the Functional and Ecological Aspect of Novel Intermittent Stream Valves for Spraying Seed Potatoes

Abstract

It is important to protect potatoes from insects and diseases at an early stage of their development. Pesticides are necessary to prevent loss caused by Colorado potato beetles feeding on potato leaves. Nowadays, there are attempts to reduce the use of chemical agents to the minimum necessary level. This article describes the construction of a novel valve that applies chemicals in an intermittent stream during potato treatment. Thus, it is possible to reduce the emission of chemicals to the natural environment. The article also describes the research site where the valve was tested, provides the results of laboratory investigations on different types of sprayer nozzles and their validation. Apart from that, the degree of the seed potato surface covering with the dressing was assessed in order to select the right sprayer nozzle and working pressure. The results of field tests of the seed dresser prototype with novel nozzles showed that they effectively dressed seed potatoes while saving 2 L (50%) of the chemical per hectare. Fissure sprayers achieved the highest degree of covering (up to 78%) with the first version of the valve (without auxiliary airflow). When the innovative valve (the second solution with auxiliary airstream) was applied at a distance of 50 mm from the seed potato fall path S, the highest degree of coverage with the dressing substance (up to 88%) was observed for the ejector sprayer. When the distance between the valve and the seed potato fall, path S was increased from 50 to 100 mm, the degree of surface coverage was lower for both of the valves used in the tests.