Diagnostic agronomy, Dubbo, 18th October 2010 Allan Mayfield, Clare, SA Nutrition P - P audits, plant tests, P rate test strips N - Soil N, plant NIR & sap N, NDVI (GreenSeeker), look at it!, Baldock model, Yield Prophet, experience Other nutrients – visual symptoms, plant tests (diagnosis & monitoring) ‘Berkshires’ Nutrition management in zones EM38 Vertical Soil water Yield Prophet Sensors – eg Sentek Metal push probes Using zones to improve soil water assessments Weeds Acceptable weed control is typically well below the economic thresholds for yield loss For herbicide resistance – Quick-Test (green plants), seed tests, herbicide test strips Weed control according to zones Ryegrass % cover /canola % cover Diseases Diseases Pre-emptive for root diseases – Predicta B test, observations in previous crop(s) For foliar diseases – when symptoms or pre-emptive. Fungicide use now very common. Varietal resistance can be a major factor in crop selection (eg CCN, stem rust, canola blackleg) Insects Some pre-emptive treatments used, especially for canola & virus control, otherwise, treat as needed. Close monitoring of crops can be critical Need to identify beneficials as well as pests Gaps include thresholds - the understanding of effect of beneficials, and the impact of pesticides Grower’s situation & attitude to risk is important Retrospective monitoring Improvements in water use efficiency Water use efficiency (kg/mmGSR), 5 year average, wheat, Redhill, SA. 2008 2006 2004 2002 2000 1998 1996 1994 1992 1990 1988 1986 1984 1982 1980 1978 1976 22 20 18 16 14 12 10 8 6 4 2 0