Effect of herbicides and frequence of irrigation on yield of corn (Zea mays L.) and accompanied weeds.

Abstract

A field trial were conducted at the experimental farm , Department of Crop Sciences,College of Agriculture,University of Baghdad,Abu-Ghraib during the fall season of 2008 and 2009 to study the response of maize crop to irrigation frequency (3.6 and 9 days) and herbicides (Acetochlor and Atrazine) on grain yield of corn and weed accompanied . A factorial experiment Block design according with split – plot with three replications was used. The Acetochlor and Atrazine gave lowest number of weed at both seasons (9.8 , 11.2 , 7.2 and 9.6 plant.m-2) respectively while weedy treatment gave high value (90.7 and 86.2 plant.m-2) respectively at both seasons and also they reduced dry weight of weed by 87.0% and 89.6% at first season and by 90.7% and 87.5% at second season according the weedy treatment , therefore they gave highest number of grain at both seasons (456 , 462 , 467 and 478 grain per ear) respectively and grain yield were (7.369 and 7.529 ton.ha-1) at first season and at second season (7.641 and 8.856 ton.ha-1) respectively while the weedy treatment gave lowest value of grain yield was at first season (3.187 ton.ha-1 and 3.102 ton.ha-1) at second season. Treatment of irrigation every three days gave height plant at both seasons were( 177.4 and 178.2 cm) also number of grain per ear (493 and 498 grain) and grain yield (7.951 and 8.157 tn.ha-1) respectively. Treatment irrigation every three days with weed-free gave superior grain yield were (10.600 and 10.420 ton.ha-1 ) respectively at both seasons while irrigation every nine days with weedy treatment lowest grain yield was ( 3.187 ton.ha-1 ) of first season and (3.102 ton.ha-1) at second season.

Keywords

herbicides, corn