Integrated Effects of Cropping System and Herbicides on Maize Competitive Traits

An experiment was set up in Maize Research Institute Zemun Polje, Serbia in 2009. Two cropping systems, maize continuous cropping and maize-winter wheat rotation, included subtreatments with different weed management: control without herbicide application and application of the herbicides isoxaflutole + acetochlor at the recommended dose (RD) and half of recommended dose (0.5 RD). After three and five years of experiment, maize harvest index, leaf area index (LAI), chlorophyll and carotenoids content as parameters of maize competitiveness, and weed biomass as parameter of weed abundance, and their interdependences were analyzed. Weed biomass was significantly decreased by herbicide application in both years and cropping systems, but there was no significant differ ences between recommended and half of recommended dose. The average weed biomass for all herbicide treatments was 33.73% lower in maizewinter wheat rotation than in maize continuous cropping. Parameters of maize competitiveness have been changed according to the level of herbicide application and to a greater extent in maize continuous cropping than in the maize-wheat rotation.