Evaluate the effect of different weed management methods and corn densities on weeds and corn yield (Zea mays L.).

To evaluate the effect of different weed management methods and corn densities on weed and yield of corn, an experiment was conducted in 2009 at Azad University of Takestan. The experiment was a factorial based on complete block design with four replications.  Treatments were corn density in three levels (recommended density, 16 Plant.m-2); 25% and 50% more than recommended density) and weed management in five levels (hand weeding, without weeding, nicosulfuron herbicide in two and four leave stages of corn life cycle, once and two times cultivator). The results showed that the corn densities had significant effects on density and dry matter of prostrate pigweed (Amaranthus blitoides), corn biomass and total weed densities and biomass. Different weed management methods had significant effects on all weed species, but no significant effects on corn. The interaction effect between corn densities and different weed management methods on prostrate pigweed density was significant. Finally, the best corn density for weed controlling and achieving the higher biological yield in corn is 50% above the recommended density (39155 kg. ha-1). Also, among different weed management methods, one-time cultivation is the most suitable treatment compared to twice cultivations and hand weeding.