Comparison of Mechanical, Agronomic and Chemical Methods for Control of Echinochloa Crus-galli, Amaranthus Retroflexus and Convolvulus Arvensis Weeds of Corn Fields

In order to evaluate the efficiency of non-chemical and chemical methods and their simultaneous use to control of weeds (Echinochloa Crus-galli, Amaranthus Retroflexus and Convolvulus Arvensis) in maize, a split plot experiment was conducted in the randomized complete block design in three replications and implemented at Varamin-Iran. The main factor (A) was non-chemical treatments consisted of three levels: AM: Irrigation before sowing (agronomic), AC: cultivator (mechanical) and A0 (without agronomic or mechanical operations). Sub-factor was (H) of chemical treatments include three levels of HFS (Foramsulfuron (at a rate of two liters per hectare, HNS (nicosulfuron at a rate of 1.5 liters per hectare), HA + G (atrazine and Gazaprim) and H0 (manual weeding by hand), respectively. The number of Amaranthus Retroflexus and Convolvulus Arvensis weeds (compared to the control) decreased by about 90% with the irrigation before sowing (Am) or cultivator (AC), and the increase in yield (compared to the control) was about 55-60%. While the non-chemical treatments (agro-mechanical) had no effect on reducing the number of Echinochloa Crus-galli weed. Nicosulfuron herbicide, similar to hand weeding (H0), controlled more than 90% of the Amaranthus Retroflexus and Convolvulus Arvensis weeds, but only 70% of the Amaranthus Retroflexus and Convolvulus Arvensis weeds. There was no significant difference in terms of corn grain yield (8000-8500 kg / ha) between hand weeding (H0) and nicosulforn herbicide (HNS) in plots in with agro-mechanical operations. However, in plots where agro-mechanical operations (A0) were not performed, hand weeding (H0) had 12.5% ​​higher corn grain yield compared to Nicosoluren herbicide application (HNS). Therefore, for Echinochloa Crus-galli, a combination of Irrigation-nicosulfuron and cultivator-nicosulfuron treatments is proposed.