Managing herbicide resistant annual ryegrass (Lolium rigidum Gaud.) in no-till systems in Western Australia using occasional inversion ploughing

摘要

Sites at Katanning and Beverley, Western Australia, were selected in 2002 to investigate the efficacy of mouldboard ploughing for the control of herbicide resistant annual ryegrass populations. The mouldboard plough was compared with disk ploughing, full cut and no-till tillage regimes. Cereal crops were planted and assessed in 2002 and 2003. Mouldboard ploughing reduced the number of annual ryegrass seedlings by over 95% at both sites in 2002, compared with the other tillage treatments. The differences in annual ryegrass density were maintained into the 2003 crops. Cereal yields were significantly higher on mouldboard ploughed plots at Katanning in 2002 and 2003 and at Beverley in 2002. Mouldboard ploughing shows great promise as a one-off treatment to 'reset' the resistance clock. It is estimated that an inversion treatment may only be required once every 8-10 years.