On-farm investigations on integrated weed management in maize in three European countries

In 2011 and 2012, a total of 9 on-farm experiments were conducted to evaluate the effectiveness of different integrated weed management strategies (IWM) against the conventional approach (CON) in three important European maize producing countries. These sites were located in Italy, Germany and Slovenia and represent the range of various geographic, climatic and cultivation types in Europe. The IWM strategies tested were: 1) Italy: the early-post emergence herbicide broadcast application when-if indicated by a predictive model of weed emergence after performing one scouting in the field, followed by hoeing, 2) Germany: the early-post emergence band application combined with hoeing followed by a second hoeing and 3) Slovenia: the harrowing at BBCH 12-13 of maize and low doses of post-emergence herbicide. Results showed that the different IWM strategies tested in the countries were similarly effective with the CON broadcast herbicide application in reducing weed density. In terms of mean weed density in the 3 countries and 2 years the efficacy of CON was significantly higher than IWM in only 2 out of 6 trials across two growing seasons. Furthermore, there were no significant differences of both management strategies in terms of grain yield. The study highlights the potential of IWM tools already available in Europe.