Effect of soil applied herbicides and depth of sowing on common cocklebur (Xanthium strumarium L.) and maize (Zea mays L.) emergence and early growth

Greenhouse trials were conducted during 2005 to investigate the effect of six soil applied herbicides on common cocklebur (Xanthium strumarium L.) sowed at a depth of 4 cm and 7 cm, and determine the potential injury to maize by the herbicides and the influence of sowing depths. The efficacy of all herbicides was high, regardless of sowing depth and, generally, the coefficient of efficacy ranged from 86.3% to 100.0%. Most of the herbicides had no significant phytotoxic effect on maize plant density/container, height and fresh weight of maize. Exceptions were Atranex-90WDG and Cyatral-SCZ, which caused serious injury to maize (33% and 37%, respectively) if seeded at a depth of 7 cm, and significantly reduced height and fresh weight of the plants.