Investigations of the effective minimum rates of Foramsulfuron against weeds in maize growing areas in Aydin province

Pot and field experiments were carried out at researh and application farm of Adnan Menderes University, Faculty of Agriculture in 2006-07 with the aim of determining the effective minimum rates of foramsulfuron based on the weed species. Furthermore the relationships between efficacies of effective minimum rates and weed growth stage, as well as environmental factors were investigated in these studies. In pot experiments aiming determination of effective minimum rates (ED90) of foramsulfuron, it was observed that different weed species showed different herbicide sensitivity, and so effective minimum rates were determined for each weed species. In field experiments it was confirmed in most cases that the effective minium rates provided similar weed control as with the recommended herbicide rate. Addition of ammonium-sulphate fertilizer at 1 % v/v to spray solution improved the efficacy of minimum rates. In both pot and field experiments weed growth stage was found to be as an important factor influencing the efficacy of effective minimum rates and weeds were found to be more sensitive to herbicide at earlier growth stages. Environmental conditions affected the herbicide performance, so that the conditions favoring weed growth increased the herbicide performance as well. In both pot and field experiments no phytotoxicity of herbicide on maize plants was observed.