Jack Desbiolles (University of SA), Lynne Macdonald (CSIRO), David Davenport (Rural Solutions SA), Mel Fraser (Rural Solutions SA), Nigel Wilhelm (SARDI), Brett Masters (Rural Solutions SA)
|Contributor||SARDI Minnipa Agricultural Centre|
Site 2, Murlong, SA
Previous work on Eyre Peninsula at Wharminda (Wilhelm, unpublished data) investigated the impact of two soil wetter chemistries applied within the seed row on crop establishment and grain yield. This work showed that both wetting agents increased cereal crop establishment in most trials over three years, but this rarely translated into grain yield benefits (1 trial in 6, with 1 wetting agent). This experience contrasts with extensive work in WA (e.g. Davies, 2018) suggesting soil moisture conditions at seeding have a major influence of crop response to soil wetters. Using soil wetters while dry seeding in repellent sands achieved average grain yield increases of 11% (10 trials), and 18% when dry seeding in repellent forest gravels (6 trials). These grain yield responses to soil wetters significantly reduced when seeding occurred after a reasonable rainfall, dropping to non-significant (7 trials) and to 5% average yield benefit (3 trials), respectively.
This 2018 trial was established at Murlong as part of the GRDC funded and CSIRO-led ‘Sandy Soils Project’ and is investigating water repellence mitigation options at seeding. The trial aims to identify the driving chemistries (surfactants vs humectants) and application techniques (furrow surface, vs seed zone) that are better able to lift crop responses under local sowing conditions. This article reports on the Year 1 data, with more work being planned for the 2019-20 seasons.
|Lead research organisation||
Commonwealth Scientific and Industrial Research Organisation
|Host research organisation||
SARDI Minnipa Agricultural Centre
|Trial funding source||GRDC CSP00203|
Sandy soils in low and medium rainfall areas
Funding from the GRDC (CSP00203), technical assistance from Dean Thiele (UniSA) and Ian Richter (SARDI) with trial implementation and data sampling, the collaboration and support from the soil wetter suppliers listed in Table 1 are all gratefully acknowledged. Thank you also to Syngenta Australia, Nufarm/CropCare, Incitec Pivot Fertilisers and Wengfu Fertilisers for some in-kind support.
|Other trial partners||University of South Australia, the SA state government through Primary Industries and Regions SA, Mallee Sustainable Farming Inc. and AgGrow Agronomy.|
|Sow rate or Target density||Wheat CL Razor wheat sown at 63.2 kg/ha targeting 155 plants/m2 at 80% establishment, Targeted seeding depth: 30-35 ±5 mm|
Seeding system: knife point double shoot combined with twin seeding discs with press wheels (row spacing = 0.28 m), sowing speed: 5 km/h, sowing date: 21-23 June 2018
|Sow date||22 June 2018|
|Harvest date||3 December 2018|
|Plot size||25 m x 1.68 m|
|Plot blocking||randomised complete block design|
|Plot randomisation||randomised complete block design|
|Paddock history||2017: Barley 2016: Pasture 2015: Barley|
Weed control: Agrityne 750 @ 1.5 L/ha at late tillering
|Seed treatment||Rancona C + Imidacloprid 600.|
|Rainfall avg ann (mm)||332mm|
|Rainfall avg gsr (mm)||249mm|
|Rainfall trial total (mm)||220mm|
|Rainfall trial gsr (mm)||167mm|
SILO weather estimates sourced from https://www.longpaddock.qld.gov.au/silo/
Jeffrey, S.J., Carter, J.O., Moodie, K.B. and Beswick, A.R. (2001). Using spatial interpolation to construct a comprehensive archive of Australian climate data , Environmental Modelling and Software, Vol 16/4, pp 309-330. DOI: 10.1016/S1364-8152(01)00008-1.