Efficacy of four post-emergence herbicides applied at reduced doses on weeds in summer maize (Zea mays L.) fields in North China Plain

• Published in: Crop protection Vol. 52; pp. 26 - 32
• Main Authors: Zhang, Jinwei, Zheng, Li, Jäck, Ortrud, Yan, Dayu, Zhang, Zongjian, Gerhards, Roland, Ni, Hanwen
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2013
• Subjects: corn; Crops; developmental stages; Dose reduction; field experimentation; Grain yield; grass weeds; mesotrione; nicosulfuron; Nicosulfuron/mesotrione; summer; Topramezone; Weed control; Zea mays; China; China, People's Rep., North China Plain; Weed control; Nicosulfuron/mesotrione; Topramezone; Grain yield; Dose reduction
• ISSN: 0261-2194; 1873-6904
• DOI: 10.1016/j.cropro.2013.05.001

Field experiments were conducted in 2010 and 2011 in a typical location of North China Plain to evaluate weed control efficacy of four post-emergence herbicides nicosulfuron, mesotrione, topramezone and the combination of mesotrione/nicosulfuron when they were applied at reduced doses at different weed growth stages. Experimental results showed that nicosulfuron, topramezone and the combination of mesotrione/nicosulfuron provided better weed control efficacy than mesotrione when they were applied at their label recommended doses at the 2- to 3-leaf and 4- to 5-leaf stages of weeds; nicosulfuron and mesotrione/nicosulfuron could at least be reduced by 33% and topramezone reduced by 67% without sacrificing total weed control efficacy and maize grain yield. Nicosulfuron and its combination with mesotrione could effectively control broadleaved and grass weeds when their doses were reduced by 67% and by 33%, respectively. Topramezone could effectively control broadleaved and grass weeds when its dose was reduced by 67%. The efficacy of mesotrione in controlling grass weeds was bad even at the label recommended dose. All four herbicides tested did not affect the maize grain yield. •Higher nicosulfuron, topramezone, mesotrione/nicosulfuron efficacy than mesotrione.•Nicosulfuron and mesotrione/nicosulfuron could be reduced by 33% for weed control.•Topramezone could be reduced by 67% for broadleaved and grass weed control.