Evaluation of spectrum efficacy of registered herbicides used in corn

In order to study the efficacy of some applied herbicide used in grain corn an experiment was carried out in a Completely Randomized Block design with four replications and 18 treatments in Ahvaz، Varamin، Jiroft، and Isfahan. Treatments were the full–season hand weeded control، and post emergence (POE) applications of 2، 4-D plus MCPA at 1. 5 lit. ha-1، Bromoxynil plus MCPA at 1. 5 lit. ha-1، Nicosulfuran at 2 lit. ha-1، and Furamsulfuron at 2 lit. ha-1، pre-planting (PP) application of EPTC plus Dichloramide at 5 lit. ha-1 and pre-emegrcne (PE) application of Pendimethaline at 4. 5 lit. ha-1، and combination application of EPTC plus Dichloramide (PE) at 5 lit. ha-1 plus 2،4-D pulsMCPA (POE) at 1. 5 lit. ha-1 or Bromoxynil+MCAP (POE) at 1. 5 lit. ha-1، or Atrazine (PE) at 1 kg. ha-1، Alachlor at 5 lit. ha-1 (PE) plus 2، 4-D puls MCPA (POE) at 1. 5 lit. ha-1 or Bromoxynil+MCAP (POE) at 1. 5 lit. ha-1، or Atrazine (PE) at 1 kg. ha-1 and Acetachlor at 4. 5 lit. ha-1 plus 2، 4-D puls MCPA (POE) at 1. 5 lit. ha-1 or Bromoxynil+MCAP (POE) at 1. 5 lit. ha-1، or Atrazine (PE) at 1 kg. ha-1. Results indicated that 2، 4- D plus MCPA and Bromoxynil plus MCPA were the good to excellent option to control broadleave weeds. Johnsongrass (Sorghum halepense (L.) Pers.) was controlled excellently by two herbicides «Nicosulfuron and Furansulfuron»، but the efficacy of two mentioned new herbicides on barnyardgrass (Echinochloa crus-galli (L.) Beauv.) were moderate to good and on common purslane (Portulaca oleracea L.) was moderate. Pendimethalian had the good to excellent effects on barnyardgrass and broadleave weeds، but it had no effect on johnsongrass and bermudagrass (Cynodon dactylon (L.) Pers.) Generally، the efficacy of 2، 4-D plus MCPA and Bromoxynil plus MCPA on broadleave weeds were better than Atrazine. Additioinly، Acethalchlor was better than Alachlor for controlling narrow leaves and broaleaves weeds. All treatments were safe for corn.