Influence of disc seeding systems on pre-emergence herbicide control of annual ryegrass (Lolium rigidum) in wheat

摘要

Pre-emergence herbicides placed too close to crop seed can cause crop damage. No crop damage was observed from pre-emergence herbicides when used with triple disc seeders. In contrast, crop damage caused by pre-emergence herbicides varied considerablybetween different single disc configurations. Pyroxasulfone caused no damage to wheat and provided >79% control of annual ryegrass and appears to be the most suitable pre-emergence herbicide for use with single discs. By comparison, trifluralin significantly (P <0.05) reduced wheat density in single discs (<50%) but not with triple disc seeders. Crop damage from trifluralin and prosulfocarb + S-metolachlor in single discs was significantly reduced (<20%) when residue managers were fitted in front of the disc blade. Increasing the operating depth of the single disc by 15 mm also reduced crop damage from trifluralin and prosulfocarb + S-metolachlor.