ABSTRACT Targeted application technologies combine imaging systems for weed detection with single nozzle control for herbicide application. The potential of herbicide saving using targeted application is very high because weeds are usually distributed heterogeneously in agricultural fields. This study presents a real‐time system for single weed plant control in maize. The targeted application technology is integrated in a conventional 36 m wide boom sprayer. Ten field experiments were conducted in maize, five in 2023 and five in 2024. Two experimental sites were in East‐Germany, two in Southwest‐Germany and one in Hungary. All experiments included an untreated control, a broadcast herbicide application and a targeted application. Identical herbicides were used in both application systems. The embedded imaging processing unit segmented the plants from the soil and calculated the weed coverage (%). If weed coverage was higher than 0%, the spray nozzle was activated and one spot treatment applied. Targeted application was realised at a driving speed of 10 km h −1 . Weed control efficacy (%) (WCE) was calculated based on weed density counts before and 14 days after herbicide application. Targeted application achieved on average 25% herbicide savings in both years ranging from 2% to –73%. Targeted application achieved 72%–99% WCE. Maize yield and WCE did not differ between broadcast and targeted application in any of the 10 experiments. This study shows that targeted application technology can be integrated into large conventional boom‐sprayers without hindering the herbicide application and performance. Further savings could be realised if the imaging system would classify between different weed species, economic weed threshold would be applied and spray nozzles covering less area would be used.
Gerhards et al. (Sun,) studied this question.