The effect of nitrogen source, operation method and weeds control methods on weed biomass, yield and yield components of corn (Zea mays L.)

In order to study of the effect of nitrogen source، operation method and weed control methods on weed biomass، yield and yield components of corn (Zea mays L.) an experiment was carried out as split plot factorial based on randomized complete block design (RCBD) with four replications in Shahrood University of Technology. The treatments included weed control methods at four levels (hand weeding at all growth season، weedy، EPTC herbicide at regular dose and 50% regular dose as main factor)، nitrogen source at two levels (urea and Ammonium sulphate) and operation method at two levels (band and broadcast) as sub plot. Results showed that EPTC herbicide at regular dose and band operation method reduced weeds biomass more than EPTC herbicide at 50% regular dose and weedy check treatments. Weed control methods significantly affected grain yield، 1000-seed weight، seed row number per ear، seed number per row، ear length، biological yield and ear weight traits. Nitrogen source significantly affected only ear length and ear diameter. The interaction of nitrogen source and weed control method significantly affected only ear length and ear diameter. Hand weeding at all growth season and EPTC herbicide at regular dose produced maximum grain yield. Grain yield for EPTC herbicide at 50% regular dose and weedy treatments was same and at least. Seed row number per ear and 1000-seed weight traits were maximum for EPTC herbicide at regular dose and at least for EPTC herbicide at 50% regular dose and weedy treatments. Interaction of weed control methods and nitrogen operation method significantly affected seed number per row of corn.