Success of diagnostic approach to rainfed, wheat-based cropping systems in Western Australia

Deterioration of crop yields due to exploitive cropping systems (CS) is a worldwide problem reducing profitability for farmers, food availability for consumers and inducing poor utilisation of rainfall. Following a diagnostic approach, likely constraints were identified and corresponding remedies tested in factorial experiments over three years at two sites in the central grain belt of Western Australia. The constraints at the first site (York, sandy clay loam soil) were high cereal cyst nematode (CCN), low cation exchange capacity (CEC) and soil compaction; and the remedies tested were CCN resistant cultivar, green manuring and deep ripping (DR). The constraints at the second site (Beverley, leaching prone sandy duplex soil) were high weed burden (ryegrass, Lolium rigidum L.), soil compaction, low pH and low CEC; and the remedies tested were repeated hay crops, deep ripping including lime application, and green manuring. Nitrogen applications on the cereal crops were split between sowing and after heavy rainfall events at the Beverley site.