• Incorporating seed behind press wheels resulted in the best crop establishment and one of the higher yields.
• A split application of seed, some broadcast in front of the seeder and some sown through the seeding boots shows promise.
• Soil wetters were ineffective for increasing emergence or grain yield.

Increasing plant density is a tool to improve a crop’s competitiveness against weeds. This strategy did not adversely affect the yield of the varieties at the Liebe Main Trial Site in 2012. 

Nitrogen treatments did not significantly influence crop yield however, did influence grain protein. The soil nitrogen levels and season are likely to have influenced this result. Soil testing and understanding the crops requirements as the season unfolds are useful strategies to manage crop performance economically.

The environment is likely to have had the bigger influence on the performance of the varieties than plant density or nitrogen. Growing season rainfall for 2012 was lower than average and disease patches (likely Rhizoctonia) were evident at the trial. The water use efficiency at the site was 13 kg/mm given growing season rainfall (April to October) was 133mm (plus 34mm in January) and grain yields of 1.98 t/ha across whole trial.

• Cobra and Mace were significantly higher yielding than Emu Rock at all seeding densities (P<0.05). There was a yield increase for Emu Rock and Cobra when plant density increased from 83 plants/m2 to 130 plants/m². Further  increases in plant density did not improve or reduced grain yield of these varieties. There was a yield increase for Mace from 130 plants/m2 162 plants/m2. Increasing plant density did not influence grain screenings which were less than 2% for all varieties.
• At Badgingarra, nitrogen application at seeding (14, 30, 60 and 90 kg/ha) did not affect grain yield at either seeding densities (data not provided).   The soil was a red sandy loam with nitrate levels in the top 20 cm of soil at 55mg/kg.   Protein levels in the grain were in excess of 12.5% for all treatments and varieties.  The higher split nitrogen application did significantly increase protein by 0.4% however without a yield increase the late N application was not economical.   This may be a strategy to consider for high yielding varieties such as Mace.  At the higher plant density, and higher yield, Mace had lower protein than Cobra and Emu Rock.  

• Cu and Zn basal in 1957

• Mo and Mn applied as cross strips in 1959

• Only a end of the experiment showed pale clover and a marked response to Mo.

• Conclusion little chance of Mo reponses ; unlikely to be extensive areas of Mo defiicency on this soil type in the district

Mn defiiecy patches noted through the experiment al. Nil Mn were more severe 

Topdressed Mn appeared the have similar symptoms to nil Mn

Drilled Mn at the low and high rate had less Mn symptoms

Mn foliar sprays had less Mn yellow patches.

Mn foliar sprays improved dry matter production by about 350 kg/ha in early- September

Mn foliar increased dry matter by 1200- 1500 kg/ha by late-September.

Topdressed Mn less effective than drilled

• Chlorotic and stunted wheat was found to have higher shoot manganese content than healthy plants in the same fields • High values were sometimes associated (correlated) with soil acidity and sometimes with waterlogging.
• In experiments, direct drilling resulted in lower manganese content of wheat, while what following lupin had higher manganese than wheat following wheat.
• Application of lime (0, 2.5 and 5 t/a) to an acid soil (pH 5) reduced the manganese content of wheat from 373, to 135 and 191 ppm respectively.
• On soil from a problem paddock near Rutherglen, application of ammonium sulphate nearly doubles manganese content of Olympic but not Egret wheat, while calcium nitrate reduced manganese in both cultivars.

• Manganese deficiency has been identified on light volcanic soils from Mounts Gambier and Schank, and heavy black soils from drained swamps near Penola.
• These soils are alkaline.
• Symptoms first appear as oval dead spots on the second leaf, especially along the margins (not on the first leaf).
• Availability of manganese is reduced in the alkaline soil.
• The deficiency can be cured by the application of manganese sulphate.

• There was no yield response to Mn fertiliser.
• Plant and seed testing confirmed that this site had no requirement for Mn fertiliser, but they did show increased Mn levels with increasing supply.
• Claying in 2008 probably reduced the likelihood of Mn deficiency by improving soil moisture relations and therefore Mn availability.

• Summary of 8 experimentsover 3 seasons esperiments for esperance sandplain.

• For wheat, sites were selected where lipins gave a large seed reponse in the previous year. Lupins produced much split seed.

• Soil deep siliceous grey sands 

• Dtpa Mn < 3.5 mg/kg soil

• However for wheat there was no grain yield response to Mn. Grain yield ranges from 1.3 - 1.6 t/ha

• hence no determination on methods of placement were possible

• Summary of 2 experimentsover 3 seasons esperiments on  sandplain soils.

• For wheat, sites were selected where lipins gave a large seed reponse in the previous year. Lupins produced much split seed.

• Soil grey sands Deep phase gibson sand

• Dtpa Mn < 4.0 mg/kg soil

• However for wheat there was no grain yield response to Mn. Grain yield ranges from 3.5 -3.75 t/ha

• hence no determination on methods of placement were possible for wheat

• Summary of 2 experiments over 5 seasons esperiments.

• For wheat, sites were selected where lipins gave a large seed reponse in the previous year. Lupins produced much split seed.

• Wheat showed no response to freshly applied and previously applied Mn fertiliser

• Soil grey sands Deep phase gibson sand

• Dtpa Mn < 4.0 mg/kg soil

• However for wheat there was no grain yield response to Mn. Grain yield ranges from 3.5 -3.75 t/ha

• hence no determination on either methods of placement were possible for wheat

• Mn concentration in young leaves > 20 mg/ka & Mn concentration in grain > 30 both from nil Mn 

• Nor residual value fot wheat could be determined

 

• Summary of 8 experimentsover 3 seasons esperiments for west Midlands sandplain.

• For wheat, sites were selected where lipins gave a large seed reponse in the previous year. Lupins produced much split seed.

• Soil deep siliceous grey sands 

• Dtpa Mn < 3.0 mg/kg soil

• However for wheat there was no grain yield response to Mn. Grain yield ranges from 1.25 - 1.75 t/ha

• hence no determination on methods of placement were possible

• Summary of 2 experimentsover 3 seasons esperiments on  sandplain soils.

• For wheat, sites were selected where lipins gave a large seed reponse in the previous year. Lupins produced much split seed.

• Soil grey sands with little gravel

• Dtpa Mn < 4.0 mg/kg soil

• However for wheat there was no grain yield response to Mn. Grain yield ranges from 2.5 -2.75 t/ha

• hence no determination on methods of placement were possible for wheat

• There were no significant differences between the varieties for yield with all yielding close to the district average for this season.
• The potential Schooner replacement variety WI 3408 had higher protein than all other varieties and was too high to make malt standards.
• This site was harvested late (January 6, 2004) and produced low test weights. Generally low test weights result from frost or moisture stress although in this instance, rainfall before harvest caused changes in grain size that may have contributed. Low test weights were also observed at the Minyip site, which was also harvested after rain (January 3, 2004).
• While all varieties had low retention and would not have made Malt 1 as a result of this measure alone, WI 3586 had significantly lower retention than all other varieties. This line was expected to be a replacement for Gairdner with improved grain size.
• All varieties had acceptable screenings levels despite low retention.

Early sowing (15 April) had the largest positive impact on canola yield when comparing a range of treatments trialled in 2014, similar to results observed in 2013. Sowing on 15 April improved yields up to 45%, depending on variety, compared to 13 May sowing date. Good seeding depth and the correct seed rate proved important in maximising canola yield at the sites trialled in 2014, but not to the same extent as time of sowing. Sowing at 4.5 kg/ha at a 2 cm depth gave a 13% yield improvement over sowing at 1.5 kg/ha at 1 cm depth. Achieving approximately 50 plants/m2 of triazine tolerant varieties and 40 plants/m2 of Clearfield tolerant varieties was needed to maximise canola yields in trials conducted at Minnipa Agricultural Centre in 2014. Using farmer retained open pollinated seed did not cause a yield penalty when compared to commercially purchased seed in trials conducted at Minnipa in 2014.

• Early sowing (22 April) had the largest positive impact on canola yield when comparing a range of treatments trialled in 2015, similar to results observed in 2013 and 2014. Sowing on 22 April improved yields up to 12%, depending on variety, compared to 29 April sowing date.
• Different management practices are needed to establish canola on different soil types under marginal moisture conditions. On a loamy soil at Minnipa deeper sowing (to 4 cm) produced the highest yields, whereas shallower sowing (1 cm) produced the highest yields at Piednippie, particularly with the smaller seeded variety Stingray.
• Trials at Piednippie in 2015 showed that yields up to 0.8 t/ha are achievable in a below average rainfall season, provided the crop is established early and achieves around 50 plants/m2 in open-pollinated varieties.
• Results from similar trials in 2013, 2014 and 2015 have all shown that the highest yielding canola has consistently come from plots with plant establishments of over 50 plants/m2 for open pollinated varieties and 40 plants/m2 for hybrid varieties.

• Early sowing (22 April) had the largest positive impact on canola yield when comparing a range of treatments trialled in 2015, similar to results observed in 2013 and 2014. Sowing on 22 April improved yields up to 12%, depending on variety, compared to 29 April sowing date.
• Different management practices are needed to establish canola on different soil types under marginal moisture conditions. On a loamy soil at Minnipa deeper sowing (to 4 cm) produced the highest yields, whereas shallower sowing (1 cm) produced the highest yields at Piednippie, particularly with the smaller seeded variety Stingray.
• Trials at Piednippie in 2015 showed that yields up to 0.8 t/ha are achievable in a below average rainfall season, provided the crop is established early and achieves around 50 plants/m2 in open-pollinated varieties.
• Results from similar trials in 2013, 2014 and 2015 have all shown that the highest yielding canola has consistently come from plots with plant establishments of over 50 plants/m2 for open pollinated varieties and 40 plants/m2 for hybrid varieties.

Early sowing (15 April) had the largest positive impact on canola yield when comparing a range of treatments trialled in 2014, similar to results observed in 2013. Sowing on 15 April improved yields up to 45%, depending on variety, compared to 13 May sowing date. Good seeding depth and the correct seed rate proved important in maximising canola yield at the sites trialled in 2014, but not to the same extent as time of sowing. Sowing at 4.5 kg/ha at a 2 cm depth gave a 13% yield improvement over sowing at 1.5 kg/ha at 1 cm depth. Achieving approximately 50 plants/m2 of triazine tolerant varieties and 40 plants/m2 of Clearfield tolerant varieties was needed to maximise canola yields in trials conducted at Minnipa Agricultural Centre in 2014. Using farmer retained open pollinated seed did not cause a yield penalty when compared to commercially purchased seed in trials conducted at Minnipa in 2014.

Early sowing (15 April) had the largest positive impact on canola yield when comparing a range of treatments trialled in 2014, similar to results observed in 2013. Sowing on 15 April improved yields up to 45%, depending on variety, compared to 13 May sowing date. Good seeding depth and the correct seed rate proved important in maximising canola yield at the sites trialled in 2014, but not to the same extent as time of sowing. Sowing at 4.5 kg/ha at a 2 cm depth gave a 13% yield improvement over sowing at 1.5 kg/ha at 1 cm depth. Achieving approximately 50 plants/m2 of triazine tolerant varieties and 40 plants/m2 of Clearfield tolerant varieties was needed to maximise canola yields in trials conducted at Minnipa Agricultural Centre in 2014. Using farmer retained open pollinated seed did not cause a yield penalty when compared to commercially purchased seed in trials conducted at Minnipa in 2014.

Early sowing (15 April) had the largest positive impact on canola yield when comparing a range of treatments trialled in 2014, similar to results observed in 2013. Sowing on 15 April improved yields up to 45%, depending on variety, compared to 13 May sowing date. Good seeding depth and the correct seed rate proved important in maximising canola yield at the sites trialled in 2014, but not to the same extent as time of sowing. Sowing at 4.5 kg/ha at a 2 cm depth gave a 13% yield improvement over sowing at 1.5 kg/ha at 1 cm depth. Achieving approximately 50 plants/m2 of triazine tolerant varieties and 40 plants/m2 of Clearfield tolerant varieties was needed to maximise canola yields in trials conducted at Minnipa Agricultural Centre in 2014. Using farmer retained open pollinated seed did not cause a yield penalty when compared to commercially purchased seed in trials conducted at Minnipa in 2014.

• Early sowing had the largest positive impact on canola yield when comparing a range of treatments trialled in 2013. Good seeding depth and the correct seed rate were also important in maximising canola yields, but not to the same extent as time of sowing.

• Ripping to 550mm increased yeild in the deep pale sand (Dune) and yellow loamy sand (swale).
• Topsoil slotting, with soil inclusion plates attached to the rear of deep ripper tines, can increase yeild from deep sandy soils more than by deeper ripping alone.
• Deeper ripping with topsoil slotting also helped lessen grain losses from dry and hot spring weather.
• If slotting maintains the de-compaction response longer it will provide very good returnson investment.   

There is a difference between maximising biomass and the optimal biomass for maximum yield in a particular environment.

Maximising biomass creates agronomic problems such as increased foliar disease and early weed competition.

Irrigation can supply moisture during grain fill but cannot control the temperature - many of the winter wheats mature too late to avoid heat stress during grain fill. 

There is a difference between maximising biomass and the optimal biomass for maximum yield in a particular environment.

Maximising biomass creates agronomic problems such as increased foliar disease and early weed competition.

Irrigation can supply moisture during grain fill but cannot control the temperature - many of the winter wheats mature too late to avoid heat stress during grain fill. 

• Despite three years of above average rainfall, a red calcareous sandy loam at Minnipa with soil phosphorus reserves of 27 mg/kg of Colwell P has not required any added P fertiliser for maximum cereal grain yields.

• Due to the dry start to the season, germination across the trial paddock was very uneven, which may have influenced the yield results of the trial.
• It is anticipated that further soil sampling and analysis work will be carried out on this trial in 2009 to look at the residual effect of lime on the soil pH and aluminium toxicity.

• Soil application of zinc sulphate heptahydrate and zinc oxide increased grain yield of maize when applied in drills near the seed.
• Spray application of zinc also increased yield but to a lesser extent.
• Spray applications of zinc following soil application of zinc sulphate or zinc oxide did not give further yield increases.
• Zinc oxide dusting of seed appears to be a promising remedial technique.

• MFMG and SARDI funded a wheat nutrition (Granular vs. Liquid) scoping study at three sites (Sherwood, Frances and Conmurra).
• The aim was to evaluate wheat production with either granular or liquid fertiliser inputs.
• Planning is underway to expand this study in 2019 and an application for additional funding submitted.

On these two sites, the addition of copper or zinc supplements to MAP had no effect on grain yield or grain Cu or Zn content. Based on the soil test, the Horsham site could have been considered marginal for Cu, but Zn levels were not considered limiting. Soil tests for micronutrients are unreliable and diagnosis of paddocks where crops can benefit from micronutrient supplements is also unpredictable.

Mid-row banding nitrogen at 133 kgN.ha⁻¹ gave a similar response to topdressing the same rate at GS31. It increased yield by 1.38 t/ha and grain N by 38 kgN.ha⁻¹ to give an ANRE of 30%. Mid-row banded N created a highly-concentrated band of ammonium which appeared to mostly survive a water-logging event.

Mid-row banding N appears to be a valid application method for nitrogen in a southern Riverina irrigated context, allowing all nitrogen requirements to be placed in the soil at sowing. This is applicable where a higher yield potential is known with some confidence, and seeding equipment can handle larger amounts of fertilizer at sowing. Hence, it may also be a useful technique in higher rainfall zones, where yield potential is high and waterlogging is more common.

On heavier soil types with higher levels of organic matter, using a speed tiller to incorporate a wheat stubble may assist in increasing canola yields. If incorporation occurs immediately post-harvest, then the addition of nitrogen may not be required if the soil nitrogen levels are adequate. If incorporation is delayed and occurs immediately prior to sowing, then the addition of nitrogen should be considered.

• Molybdenum fertiliser increased wheat grain yield in 2 of 5 years and grain weight in 3 of 5 years, indicating a deficiency of molybdenum in the soil.
• Manganese concentration in wheat grain was high but was greatly reduced following liming.

• Grazing did not change grain yield or quality. Rather, moisture stress was more important in a dry finish
• In a dry year, the ratio of grain yield to crop biomass at flowering is 0.40. In an average year it is around 0.55
• Grazing slows crop maturity by one to two weeks, which meant Revenue (long season variety) was still booting during the October heat wave 

• A comparison of 2001 and 2010 soil analysis suggests that organic carbon levels may have declined over the 9 year competition, irrespective of the rotation utilised and production achieved.
• However to suggest that there is a continuing long term decline in soil health in the face of improved “sustainable” farming techniques is premature.
• The competition ceased in its current form in 2010 with all paddocks sown to an oilseed (canola or juncea).

• Depending on seasonal influence, stored soil moisture, soil nutrition, stocking rate management and correct timing (early tillering at growth stage (GS) 18-22, rather than later tillering at GS 24-28), grazing can be done with no detriment to crop yield.
• However, preceding paddock history had a significant impact on subsequent crop success and needs to be considered when planning future rotations.

• The repeated Gairdner control plots showed variation across the site and therefore it is difficult to draw conclusions from this data.
• All varieties yielded well – especially given the below average growing season rainfall.
• All varieties had low test weight. Low test weights were also observed at the Marnoo site. The Minyip and Marnoo sites both had lower growing season rainfall and had grain discolouration as a result of rain damage before harvest, compared to the Rupanyup sites. These factors may have contributed to low test weights at the Minyip & Marnoo sites (harvested January 3 and January 6, 2004 respectively). 
• All varieties had protein levels above the malt receival standards of 12%. The high protein coupled with high yields at this site suggests high soil nitrogen levels.

The moisture probe network has been a great tool to teach growers in the region how to read moisture graphs and use this data to make informed managements decisions.  Growers can see how various urea application rates and stubble cover effect soil moisture.

• Crop intensive farming systems are running down soil carbon.
• Mixed species cover cropping offers a new approach that may address the issue.
• Local guidelines need to be developed so that farmers can make informed decisions about incorporating cover crops into their farming systems.

• Crop intensive farming systems are running down soil carbon. 
• Mixed species cover cropping offers a new approach that may address the issue.
• The cover crop species grown in 2019 had no influence on the growth, yield and grain quality of the wheat over-sown in 2020.

• Grazing vetch and lucerne can be used as a management strategy to improve lamb dry matter intake and growth rates during the late spring and early winter feed gaps.
• The Grazfeed decision support tool has predicted that while both legume forages (vetch and lucerne) will increase methane output (gCH4/day), there is a reduction in methane output per unit of animal product (gCH4/day/100gADWG).
• Moisture limitations can affect herbage production of lucerne, which in turn reduces the chances of growing lambs to achieve the full potential dry matter intake in low rainfall mixed farming systems.

• The difference in soil organic carbon (SOC) changes between nine sites across eastern Australia was largely characterised by mean temperature and rainfall.
• High temperature strongly interacted with management practices (stocking rate, nitrogen application and residue incorporation) to reduce carbon sequestration despite favourable rainfall.
   

• In sand over clay soils, bleached A2 horizons restrict root growth.
• Incorporation of clay and organic material into the A2 horizons delivered greater dry matter production but yield results varied.

Experiment started in 1983

1996:

80 g Mo/ha in 1983 was as less efective than Mo topdressed in 1997.

320 g/ha of Mo in 1996 gave maximum dry matter production of clover; about a 20% increase.

Residual value of Mo for subclover growth at recommended rates lasted about 13 years.

Soil pH was 4.4 with low soil extractable Al; residual value would be expected to be less as soil pH decreases & Al increases

Experiment started in 1992 reddish brown sandy loam ; soil pH (CaCl2) of 5.7.

1992:

Small (15%)  response to limesand at 1.5 t/ha & to Mo application applied as sodium molybdate.

Nitrogen concentration of medic increased from 4.2 to 5% with Mo application @ 200g/ha, 1.5 & 3 t/ha limesand.

limesand with Mo did not increase yield or N content compared with 200 g of Na molybdate alone.

Critical Mo concentratin in clover tops appeared to be 0.09 mg/kg

Combination of lime sand (1.5 t/ha) and 200 g Na molybdate recommended: increased dry matter produced by 30% above the control.

3 t/ha limesand produced the same yield without Mo.

 

Experiment started in 1992 reddish brown sandy loam ; soil pH (CaCl2) of 5.0.

1994:

Small (12%)  response to Mo application applied as sodium molybdate.

Nitrogen concentration of medic increased from 5.8 to 6.1% with Mo application.

limesand with Mo did not increase yield or N content compared with 200 g of Na molybdate alone.

Critical Mo concentratin in medic tops appeared to be 0.1 mg/kg

Combination of lime sand (1t/ha) and 150 g Na molybdate recommended

 A series of experiments started in 1981 and 1982 on acidic yelllow sands that are deficient in Mo.  

Yellow  sandy earths with  soil pH (CaCl2) of <4.7.

1982: Nil & 6 rates of Mo applied over 2 years

Nil Mo grain yield was about 20% of the maximum. 

Critical Mo concentratin in wheat YEB s appeared to be 0.05 - 0.06 mg/kg

The evaluation of Mo in the YEB as a reliable tissue test but suggested continuing testing into future years.

 

 A series of experiments started in late 1970'S to the earlier 1980 on very acidic yelllow sands that are deficient in Mo.  

Yellow  acidic sandy earths with  soil pH (CaCl2) of <4.5. Mo trioxide at nil, 140 & 280 g/ha was applied on original nil Mo plots.

Summary of the Mo on very acidic yellow soils:

 With ammonium nitrate the recommended rate of Mo (140 g Mo trioxide) was  inadequate for wheat grain 2 -3 years later.. 

Mo effectiveness rapidly declines with 2 to 3 years after the application.

A general conclusion for this experimental series:_  The residual effectiveness of Mo for cereal is likely to vary widely in different situations depending on soil pH, soil content of free iron, aluminium and manganese and the rate and type of nitrogen fertliser applied to the crop.

Critical Mo concentratin in wheat YEB s appeared to be 0.03 - 0.06 mg/kg. The evaluation of Mo in the YEB as a reliable tissue test but suggested continuing testing into future years.

 

 A experiment started in 1965 on acidic yelllow sands that are deficient in Mo.  

Yellow  sandy earths with  soil pH (CaCl2) of <4.5. Mo trioxide at nil, 140 & 280 g/ha was applied in 1965

Mo application of 1965 continued to supply Mo to the 1980 wheat crop, but with only about one-tenth the effect of the 1980. Ammonium sulfate depressed Mo uptake ; sodium nitrate enhanced uptake. With ammonium sulfate the recommended rate of Mo (140 g Mo trioxide) in 1965 appeared inadequate for wheat 15 years later.. 

Critical Mo concentratin in wheat YEB s appeared to be 0.03 - 0.05 mg/kg. The evaluation of Mo in the YEB as a reliable tissue test but suggested continuing testing into future years.

 

• On a low molybdenum soil the seed molybdenum concentration in the sown seed had no effect on the molybdenum concentration of the harvested seed.
• Application of nitrogen decreased seed molybdenum concentrations in a low molybdenum soil but not in an adequate molybdenum soil.

• Although the seed molybdenum content of maize is very low, there is a minimum critical level needed for healthy seedling growth.
• A seed molybdenum concentration of 0.02ppm is required for healthy seedling growth.
• Once the seedlings are established they become efficient extractors of molybdenum from soil.

• Six sites in north-east Victoria on acid duplex soils were sampled monthly to monitor manganese concentrations in soil and weed crops in relation to changing seasonal conditions.
• Cool and/or moisture conditions were associated with exchangeable manganese of less than 50 ppm.
• High concentrations of exchangeable manganese (120 – 250 ppm) were associated with waterlogging or prolonged hot dry conditions.
• The rate of increase in exchangeable manganese was greatest under waterlogged conditions in winter there was a lack of more than one month before significant increases were observed.
• Manganese concentrations in wheat tops reached 800 – 1200 ppm at the 3 sites most severely waterlogged during 1981.
• At the better drained sites the concentrations were less than 400 ppm.
• It seems that high levels of exchangeable manganese during summer have little effect on subsequent wheat crops.
• Waterlogging may result in increased concentrations of plant manganese but perhaps only in young plants or after prolonged exposure, by which time other effects of waterlogging may already have severely limited growth.

• In 2018 and 2019 Sothis increased soil levels of the root lesion nematode P.neglectus when compared to chemical fallow trial strips.
• During the 2020 season Rhizoctonia levels increased from zero to high risk levels in oats with Sothis germinating underneath.
• Monitoring of soilborne diseases through different rotations and seasons helps increase understanding of the impact on our farming systems

• At both Yarrawonga and Dooke, Victoria, there was no yield response to nitrogen application, with yields of 4.34 and 3.88t/ha respectively.
• Although there was no yield response, there was a significantly higher dry matter (DM) production and greater nitrogen offtake as a result of applying nitrogen at both sites.
• The maximum nitrogen offtake in the unfertilised crops at both sites equated (approximately) to the level of available nitrogen at the start of the season during April (assessed 0-60cm).
• The normalised difference vegetation index (NDVI) response assessed at first node stage (GS31) and the subsequent divergence of NDVI suggested that both sites would benefit from additonal nitrogen; however, late moisture stress and high temperatures compromised any potential yield response.
• The NDVI canopy scores taken at Dookie during October 2015 from the 120kg N/ha plots clearly show are more rapid senescence than unfertilised crops (control) or those crops fertilised with 60 kg N/ha.

• The last application of nitrogen was applied on the 20th July. At this stage Yield Prophet indicated that to meet full potential an application of nitrogen was required. The plant available water (PAW) was 37mm at this time giving us approximately 30 days before the crop became moisture stressed. This gave us confidence to apply nitrogen knowing that the crop would continue to grow well for 30 days even without rain.
• This site was very responsive to Flexi-N. Three applications (banded, Z13, and Z30) of 40 L/ha Flexi-N in creased yield from 1.8 t/ha to 3.2 t/ha. The nitrogen use efficiency from applied Flexi-N was 27 kg grain/kg N.
• There were early responses to 85 kg/ha Agstar before N supply became limiting.
• Plant tests in July indicated that molybdenum (Mo) was deficient (as low as 68 ug/kg with 85 kg/ha Agstar Extra), so 100 g/ha sodium molybdate was applied across the trial.
• Grain protein was low (8 to 9%) due to yield dilution. Grain tests showed marginal sulphur (S) concentrations (average 0.10 mg/kg) which may have been detrimental to baking quality characteristics such as dough strength and extensibility.

• The trial at Morawa compared a canola-wheat sequence to a wheat-on-wheat sequence with either high or low input levels. Low input had lower fertiliser, lower seed density and cheaper herbicide options. We also incorporated a comparison of a very early wheat cultivar (Zippy) to a medium maturity cultivar (Wyalkatchem).
• Water use by the crop was estimated from the sum of the in-season rainfall and the change in soil water between sowing and harvest. By estimating the amount of soil evaporation as one third of in-season rainfall, we determined the amount of water used by the plant as transpiration. The ratio of crop yield to transpiration is the transpiration efficiency of the crop which has a potential of around 20-22 mm/kg/ha.
• The yield of Zippy was more stable than that of Wyalkatchem, but the earlier maturity resulted in a substantial yield penalty. Zippy yielded around 2 t/ha each year whereas Wyalkatchem responded more in better years. The yield penalty associated with the earlier maturing variety was not offset by the higher input level. Higher input actually increased the variability in annual gross margins.
• So far Wyalkatchem has a substantially greater cumulative gross margin than Zippy and there is little difference between the high and low input strategies.

• The trial at Morawa compared a canola-wheat sequence to a wheat-on-wheat sequence with either high or low input levels. Low input had lower fertiliser, lower seed density and cheaper herbicide options. We also incorporated a comparison of a very early wheat cultivar (Zippy) to a medium maturity cultivar (Wyalkatchem).
• Water use by the crop was estimated from the sum of the in-season rainfall and the change in soil water between sowing and harvest. By estimating the amount of soil evaporation as one third of in-season rainfall, we determined the amount of water used by the plant as transpiration. The ratio of crop yield to transpiration is the transpiration efficiency of the crop which has a potential of around 20-22 mm/kg/ha.
• The yield of Zippy was more stable than that of Wyalkatchem, but the earlier maturity resulted in a substantial yield penalty. Zippy yielded around 2 t/ha each year whereas Wyalkatchem responded more in better years. The yield penalty associated with the earlier maturing variety was not offset by the higher input level. Higher input actually increased the variability in annual gross margins.
• So far Wyalkatchem has a substantially greater cumulative gross margin than Zippy and there is little difference between the high and low input strategies.

• The older herbicide mixes of 25g/ha Logran and 25g/ha Logran + 800ml/ha LVE MCPA provided unsatisfactory levels of control whilst the new herbicides Velocity, Precept and the more robust Jaguar mixes provided far greater levels of control.
• Whilst the Jaguar treatments gave lower levels of control than the Precept or Velocity treatment, Jaguar has a heavier reli-ance on moisture and good growing conditions for better levels of control.
• This could explain the slightly lower levels o control with the Jaguar treatments.

• The older herbicide mixes of 25g/ha Logran and 25g/ha Logran + 800ml/ha LVE MCPA provided unsatisfactory levels of control whilst the new herbicides Velocity, Precept and the more robust Jaguar mixes provided far greater levels of control.
• Whilst the Jaguar treatments gave slightly lower levels of control than the Precept or Velocity treatments, Jaguar has a heavier reliance on moisture and good growing conditions for better levels of control.
• This could explain the slightly lower levels of control with the Jaguar treatments.

• Cereal rye has done an excellent job of providing ground cover on poor windblown sand.
• Approximately 4 t/ha of biomass was produced by the cereal rye.
• Using a mouldboard plough to incorporate cereal rye has increased soil organic carbon in the subsoil but decreased topsoil levels.

• The high level of grain yield response to soil inversion is very exciting.  However, some sites have had little or no yield response while others have achieved an excellent yield response.  The key to the future success of this technique is to improve our ability to pick responsive soil types to maximise the return on investment in this technology.
• The very high level of weed control, which in some cases has been maintained for two to three years, is also very exciting.  There is no doubt that a mouldboard plough has enormous potential to decimate a weed seed bank.  However, it is imperative that the plough is set up correctly to achieve good weed seed burial.  The Smart CV site is a good example of how it can go wrong.  This site was ploughed in a rush during seeding in 2010 with a tractor that was not ideally suited to the plough (ie. not enough horsepower).  Consequently, full soil inversion did not occur and many wild radish weed seeds were left in the topsoil.  The grower knew this at the time but persisted with the trial to test the potential of the plough.  This soil is extremely non-wetting and a very big yield response was achieved. 
• The Brennan site was established in 2009 at West Moora by Dave Gartner (AgLime) using the DAFWA three furrow plough to assess the potential for lime burial with a mouldboard plough.  The site is deep yellow sand with moderate to high water repellence (water droplet penetration time 180 seconds).  Treatment with the mouldboard plough corrected the water repellence (water droplet penetration time 0 seconds).  The site was sown to wheat in 2009 and canola in 2010.  Large yield responses were measured in both years.  As yet there has been no response to lime.
• In summary, all of the growers that have purchased mouldboard ploughs have been very happy with the performance of ploughed paddocks in 2010.  Using a plough to invert the soil of a sandy, poor performing paddock every 10 to 15 years appears to be a fast, effective and economical way of renovating a paddock back to a point of high production.  Of course this machinery will have its limitations and is not a universal panacea.  However, our early studies are very encouraging.  Research into this area is ongoing and will eventually answer some of the long term questions that continue to arise.
•  
• Some of the practicalities
• Most of the growers so far have accessed machinery directly from Europe and then shipped it to Australia in sea containers.  Some growers have purchased second hand ploughs for $30,000 to $50,000. These machines have been completely dissembled and cleaned to meet quarantine standards so there are many hours of assembly work involved.  Some growers have accessed new machines for $90,000 to $130,000 for 9 to 14 furrow machines.  The cheaper machines have sheer bolt break out while the more expensive machines have hydraulic break out.  Sheer bolt machines have their limitations when it comes to rocks and stumps but have performed well nonetheless.  All ploughs imported so far are reversible and so are suited to up and back ploughing.
• A fourteen furrow machine can be set to cut 5.5 to 7 metres.  They work to a depth of 30 to 35 cm at 8 to 10 kph.  So the large machines can plough 4.5 to 7 hectares per hour at a cost of $70 to $100 / hectare (these are figures from growers).  The power requirement is 30 to 35 hp per furrow depending on soil conditions and working depth.  In good conditions a 450 hp 4WD wheel tractor can pull a 14 furrow plough but it will struggle in low soil moisture conditions.  4WD tractors often have the problem of the wide dual wheels running over the furrow which affects the depth and form of the first furrow.  Track tractors are preferred for pulling large ploughs.
• The large ploughs (12 to 14 furrow) have mainly been set up with a tool carrier that allows them to be connected to a large tractor without three point linkage.  This allows the tractor to run on level ground.  The smaller ploughs (8 to 11 furrow) are typically pulled by front wheel assist tractors in the 300 to 350 hp range with three point linkage.  In this situation, one wheel of the tractor runs in the furrow.
• There is clearly a large wind erosion risk immediately after ploughing.  Paddocks should be sown to wheat for cover immediately after ploughing (preferably the same day).  Wheat is more acid tolerant than barley and in many cases a profitable crop can be grown in the year of ploughing.  Cereals are more tolerant to sand blasting than broadleaf crops and so are the obvious choice as a cover crop.  Pay careful attention to seeding depth as it is easy to sow deep into soft soil.  Rolling of the paddock is essential after ploughing unless your hobby is towing tractors out of bogs.  Some growers are spreading seed / fertiliser and then rolling with coil packers to establish the wheat cover crop.  Relatively light rolling (eg. coil packers) is all that is necessary to firm the top 5 to 10cm of soil after ploughing.

• This trial was an un-replicated farmer demonstration, results should be interpreted with caution.  
• Observations: 13/7/12: Crusting of the surface reduced germination in mouldboard ploughed strips.
• For further comments please see the attached trial report.

This is the 3rd wheat crop where there has been no benefit in yield or quality due to mouldboard ploughing.

 

• Gramoxone at 1.0L/Ha is the best & most cost effective treatment for fast grass control in the short period before sowing
• If the sprayed grass paddock is left un-sown for several days, the Glyphosate and Boxer Gold treatment proved to have slower visual control but more reliable grass control over the longer period (95%).
• The high rate of Glyphosate CT (2.0L/Ha) was also quite good at the later time of rating (24DAA), 1.0L/Ha did not provide acceptable control (77%)
• Rainfall after application would have greatly enhanced the activity of the soil residual herbicides such as Boxer Gold, Sakura and Outlook
• The possible foliar absorption of Boxer Gold when mixed with Glyphosate made it a clear winner in this trial. It was by far the cleanest treatment at 24 DAA in the absence of tillage. Gramoxone + Sakura(92%) & Gramoxone + Outlook (90%) were very close behind (no tillage).
• Addition of Logran B Power or Hammer did not improve ryegrass control when mixed with Roundup CT or Gramoxone.
• Addition of 500ml Alliance to 1.0L Gramoxone may improve broadleaf weed control, particularly small capeweed, but no improvement in grass control.

• The moisture results indicate that canola uses more water at a greater depth than wheat. There is less water remaining in the soil profile below 40cm under canola sown at 1 and 6 kg/ha than for the same depth under wheat. There will be less moisture accessible to a wheat crop in 2012 on the canola plots than on the fallow plots.
• The use of fallow for moisture storage alone is unlikely given the volume of stored soil moisture at the beginning of May 2011. Indications for the use of a break crop were positive from early April. Summer rainfall had refilled the soil profile, fol-lowing the wheat of 2010, giving some surety to crop yield. Only a small rainfall event was required to break the season and join the soil moisture fronts.
• Season length and consistent rainfall has favoured yield of canola regardless of its plant density. A very plastic species as the yield from 22 plants/m2 is only 200 kg/ha less than that from 68 plants/m2. The canola plots received all required inputs as a result was a more expensive crop to grow than either the wheat or fallow.

• Application of fluid phosphorus fertiliser on highly calcareous grey soil (P responsive) at Miltaburra significantly increased shoot dry weight and uptake of phosphorus, nitrogen, zinc and manganese and increased yield by 14% compared to granular phosphorus fertiliser application.
• Application of fluid phosphorus fertiliser on red-brown calcareous soil at Emerald Rise (non P responsive) increased shoot dry weight and uptake of phosphorus, nitrogen and manganese relative to granular phosphorus fertiliser application.
• On the red brown calcareous soils the addition of nitrogen and zinc to the fluid phosphorus fertiliser increased grain yield by 11% with no effect when added to the granular phosphorus fertiliser.
• At Cowell (red brown calcareous soil) the use of zinc with fluid phosphorus fertiliser showed a small increase in zinc concentration in tissues but no other benefits.

1. Mungbean did not respond to nitrogen fertiliser with a 1 t/ha yield and a starting soil nitrogen of ~90 kg N/ha.

2. Mungbean has limited ability to maintain its water balance in high evaporative conditions. Timely in-crop rainfall/irrigation may still not maximize yields under very hot conditions during flowering to pod fill.

3. Irrigation decreased canopy temperatures by up to 8°C. 4. Charcoal rot levels increased, with the greatest rise occurring in the irrigated trial.

1. Mungbean responded to nitrogen fertiliser with a yield of +2 t/ha when planted on a low starting soil nitrogen profile (~ 50 kg N/ha).

2. One irrigation at pod-fill increased yields by up to 850 kg/ha.

3. Applying irrigation during high temperatures reduced canopy temperature, which is believed to also improve pod filling and reduce flower abortion. 4. Mungbean can increase levels of charcoal rot.

The theoretical N contribution from faba stubbles is 20 kg N/tonne of stubble. However this assumes all residue is mineralised. 

Stubble retained on the soil surface is broken down more slowly than residues present in the soil.

A 6 t/ha bean crop resulted in approximately 140 kg N/ha being released for the following season. 

• Unfortunately, crop was only sown at 40kg/ha, half the intended seeding rate. Low seeding rate and sever sub-soil compactions resulted in relatively low yields.
• There were only low levels of yellow leaf diseases.
• The site responded to N and K. With fungicide applied, there was a 0.7t/ha response to 85 kg N/ha (trt 3 v 4), and a 0.5t/ha response to 68kg K/ha (trt 2v9).
• There was a significant response to fungicide at the high rate of N, but only with K applied. This suggests the benefits of fungicide are greatest where nutrient deficiencies are overcome.
• Hectolitre weights were 74-77 kg/l and screening less than 5%
•  

Only medic based systems from 2008 and 2009 resulted in higher wheat yields in 2011.

Please see attached report.

• Growers need to be aware that glyphosate, trifluralin and diflufenican residues, plus the glyphosate metabolite AMPA, can accumulate to agronomically significant levels in certain soils.
• These findings suggest that the current risk of damage to crops in NSW is minor compared with some sites in WA that have lower rainfall and sandy soils with low organic matter.
• The risk to soil biological processes is generally minor when herbicides are used at label rates and given sufficient time to dissipate before re-application.
• However, given the frequency of glyphosate application and the persistence of trifluralin and diflufenican, further research is needed to define site-specific critical thresholds for these chemicals to avoid potential negative effects on soil function and crop production.

• Native pastures can provide valuable forage for stock.
• Barley can be sown into native pasture and taken through to harvest.
• Native pasture cropping can be managed as a viable mixed farming system in the Wimmera and Mallee.

• Richmond produced an average yield 7% higher than Soya 791 in advanced variety evaluations at early sowing dates (first week in December) over six seasons.
• Richmond produced an average yield 7.7% higher than Asgrow A6785 in advanced variety evaluations at late sowing dates (mid January) over eight seasons.
• In on-farm experiments, Richmond yielded 16% higher than Soya 791 in a wide-row system on the northern slopes, and 7% higher than Asgrow A6785 in a narrow-row coastal system.
• In addition to higher yield potential, Richmond is tolerant to lodging and pre-harvest weather damage, has clean leaf drop, large seed size and high protein, and is resistant to powdery mildew. This combination of traits provides greater crop security and a full range of market options for growers, and high quality grain for buyers and processors.

Conclusions:

The Australian soybean variety RichmondA produces large grain (22 g/100 seed) with a clear hilum and high levels of protein (42% dry matter), which is suitable for all markets including human consumption and export. The traditional variety, Asgrow A6785, has small grain (<16 g/100 seed) with a brown hilum and protein levels less than 40%, which limits the range of markets to which it is suited. The traditional variety, Soya 791, has average sized grain Agronomy(19 g/100 seed) with a light brown hilum and high levels of protein (42%). Both A6785 and Soya 791 are prone to excessive vegetative growth, especially at an early sowing date. However, this is not necessarily converted into grain yield as demonstrated in the on-farm experiment at Harwood.

RichmondA is superior to A6785 and Soya 791 in terms of grain yield, tolerance to lodging, tolerance to pre-harvest weathering and clean leaf drop. RichmondA offers a summer legume option with high yield and high grain quality for early, mid or late sowing windows in northern New South Wales. The variety’s performance was not adversely affected by the range of soil types and farming systems reported in this paper; it was superior to A6785 and Soya 791 in all situations. RichmondA is resistant to powdery mildew. This package of traits represents a significant advance in soybean varieties for the North Coast, Tablelands, Northern Slopes and Liverpool Plains production regions of northern New South Wales.

The results of the on-farm experiment of RichmondA versus Soya 791 in a wide spacing, single row system at Oakwood demonstrates the variety’s ability to compensate for wide rows and the associated lower plant populations in dryland systems. Row spacing and plant population interactions of new soybean and mungbean varieties are being investigated in the current NSW DPI–GRDC project DAN00171

Key messages: 

• Richmond produced an average yield 7% higher than Soya 791 in advanced variety evaluations at early sowing dates (first week in December) over six seasons.
• Richmond produced an average yield 7.7% higher than Asgrow A6785 in advanced variety evaluations at late sowing dates (mid January) over eight seasons.
• In on-farm experiments, Richmond yielded 16% higher than Soya 791 in a wide-row system on the northern slopes, and 7% higher than Asgrow A6785 in a narrow-row coastal system.
• In addition to higher yield potential, Richmond is tolerant to lodging and pre-harvest weather damage, has clean leaf drop, large seed size and high protein, and is resistant to powdery mildew. This combination of traits provides greater crop security and a full range of market options for growers, and high quality grain for buyers and processors.

Conclusions:

The Australian soybean variety RichmondA produces large grain (22 g/100 seed) with a clear hilum and high levels of protein (42% dry matter), which is suitable for all markets including human consumption and export. The traditional variety, Asgrow A6785, has small grain (<16 g/100 seed) with a brown hilum and protein levels less than 40%, which limits the range of markets to which it is suited. The traditional variety, Soya 791, has average sized grain Agronomy (19 g/100 seed) with a light brown hilum and high levels of protein (42%). Both A6785 and Soya 791 are prone to excessive vegetative growth, especially at an early sowing date. However, this is not necessarily converted into grain yield as demonstrated in the on-farm experiment at Harwood.

RichmondA is superior to A6785 and Soya 791 in terms of grain yield, tolerance to lodging, tolerance to pre-harvest weathering and clean leaf drop. RichmondA offers a summer legume option with high yield and high grain quality for early, mid or late sowing windows in northern New South Wales. The variety’s performance was not adversely affected by the range of soil types and farming systems reported in this paper; it was superior to A6785 and Soya 791 in all situations. RichmondA is resistant to powdery mildew. This package of traits represents a significant advance in soybean varieties for the North Coast, Tablelands, Northern Slopes and Liverpool Plains production regions of northern New South Wales.

The results of the on-farm experiment of RichmondA versus Soya 791 in a wide spacing, single row system at Oakwood demonstrates the variety’s ability to compensate for wide rows and the associated lower plant populations in dryland systems. Row spacing and plant population interactions of new soybean and mungbean varieties are being investigated in the current NSW DPI–GRDC project DAN00171

 

KEY MESSAGES:

• Richmond produced an average yield 7% higher than Soya 791 in advanced variety evaluations at early sowing dates (first week in December) over six seasons.
• Richmond produced an average yield 7.7% higher than Asgrow A6785 in advanced variety evaluations at late sowing dates (mid January) over eight seasons.
• In on-farm experiments, Richmond yielded 16% higher than Soya 791 in a wide-row system on the northern slopes, and 7% higher than Asgrow A6785 in a narrow-row coastal system.
• In addition to higher yield potential, Richmond is tolerant to lodging and pre-harvest weather damage, has clean leaf drop, large seed size and high protein, and is resistant to powdery mildew. This combination of traits provides greater crop security and a full range of market options for growers, and high quality grain for buyers and processors.

CONCLUSIONS; 

The Australian soybean variety RichmondA produces large grain (22 g/100 seed) with a clear hilum and high levels of protein (42% dry matter), which is suitable for all markets including human consumption and export. The traditional variety, Asgrow A6785, has small grain (<16 g/100 seed) with a brown hilum and protein levels less than 40%, which limits the range of markets to which it is suited. The traditional variety, Soya 791, has average sized grain Agronomy NORTHERN NSW RESEARCH RESULTS 2017 | 53 (19 g/100 seed) with a light brown hilum and high levels of protein (42%). Both A6785 and Soya 791 are prone to excessive vegetative growth, especially at an early sowing date. However, this is not necessarily converted into grain yield as demonstrated in the on-farm experiment at Harwood. RichmondA is superior to A6785 and Soya 791 in terms of grain yield, tolerance to lodging, tolerance to pre-harvest weathering and clean leaf drop. RichmondA offers a summer legume option with high yield and high grain quality for early, mid or late sowing windows in northern New South Wales. The variety’s performance was not adversely affected by the range of soil types and farming systems reported in this paper; it was superior to A6785 and Soya 791 in all situations. RichmondA is resistant to powdery mildew. This package of traits represents a significant advance in soybean varieties for the North Coast, Tablelands, Northern Slopes and Liverpool Plains production regions of northern New South Wales. The results of the on-farm experiment of RichmondA versus Soya 791 in a wide spacing, single row system at Oakwood demonstrates the variety’s ability to compensate for wide rows and the associated lower plant populations in dryland systems. Row spacing and plant population interactions of new soybean and mungbean varieties are being investigated in the current NSW DPI–GRDC project DAN00171

The application of nitrogen increased grain yield by 0.5t/ ha, but there was no benefit from additional sulphur. At this site, money was better spent on nitrogen than on sulphur.

Grain protein was very low (7-10% protein) which is becoming an issue on sandy country despite adequate nutrition.

The timing of nitrogen and sulphur applications made no difference to crop yield or quality. Consequently, growers could reduce production and financial risk by delaying some applications and adjusting rates to the seasons.

The objective of this GRDC / SPAA funded project is to increase the level of adoption of PA 'beyond guidance' by broadacre farmers. The project specifically aims to increase the level of adoption of variable rate (VR) by growers in the project to 30% by 2013.This goal will be achieved by demonstrating how to use PA tools to growers at a regional level and by increasing the skills of growers and industry in PA to a level where they can then use PA tools in their farming systems to achieve economic, environmental and social benefits.

• At Cummins, an increase of up to 100% grain yield in wheat to 5 t/ha over the control was reached by applying 120 kg N/ha (two split applications of 60 kg/ha each at emergence and before GS31) and extra irrigation (50 mm) at GS31.
• At Lock, up to a 19% higher grain yield to 5 t/ha was achieved compared to control by adding extra irrigation (50 mm) at GS31.
• At Minnipa, an increase of up to 31% grain yield to 3 t/ha over the control was achieved by adding extra irrigation (50 mm) at GS31 and applying 120 kg N/ha in two split applications of 60 kg/ha at emergence and by GS31.
• Water use efficiency (WUE) improved with N fertilisation by GS31 at Minnipa and Cummins.
• The split application of 120 kg N by GS31 may only be a good investment in paddocks where crops with N requirements (e.g. canola) were grown in the previous season or soil N at sowing was low (less than 44 kg/ha) and with average or above average seasonal soil moisture at GS31.

• Although additional nitrogen will generate extra feed the cost of application needs to be considered carefully.
• There is no point growing feed that won’t be eaten or utilised if it is costing you to produce it.
• Soil temperature will have a major impact on feed response.
• Nitrate leaching can lead to soil acidification and excess nitrates can leach into waterways so ensure application rates match plant requirements.

• Whilst additional nitrogen will generate extra feed the cost of application needs to be considered carefully.
• There is no point growing feed that won’t be eaten or utilised if it is costing you to produce it.
• Soil temperature will have a major impact on feed response.
• Nitrate leaching can lead to soil acidification and excess nitrates can leach into waterways so ensure application rates match plant requirements.

• Canola yields of 2 t/ha are possible in an average growing season (decile 5) at Minnipa Agricultural Centre.
• The total application of 85 kg/ha N and 108 kg/ha N exceeded the 2 t/ha target, producing 2.13 t/ha and 2.22 t/ha respectively, and 62 kg/ha N very nearly achieved 2 t/ha (1.96 t/ha).
• Soil tests determined that 70-80 kg/ha N was available in the soil, including mineralisation, which predicted a potential yield of 1 t/ha.

• The 2014 wheat crop at Karoonda had a harvest index of 0.4 and fertilizer N recovery was 35%.
• Wheat stubble from the 2014 crop contained 16 kg N/ha and had a C:N ratio of 95 which is common for cereal crop residues in these environments .
• Mineralization during summer resulted in the accumulation of 18-33 kg/ha of mineral N to 50cm depth across all the treatments at sowing in 2015.
• Incorporation of 2014 cereal stubble increased microbial biomass and N supply potential at sowing in the surface soil when compared with standing stubble.
• The management of cereal stubble affects the microbial activity that influences the cycling and supply of nutrients (nitrogen (N) and phosphorus) to growing crops.
• There was no significant effect of management of 2014 stubble on subsequent wheat grain yield in 2015.

• Legume pasture species and management practices have been investigated to determine the most important factors for improving nitrogen inputs to the soil.
• Results have shown significant improvements in the soil available nitrogen after growing pastures with a high proportion (>75%) of legumes.
• The increased soil nitrogen from good stands of pasture legumes is also reflected in the yield and quality of wheat grown the following year.
• A short pasture (2-3 seasons) will provide a significant increase in soil nitrogen and a yield and/or protein response. A long pasture (5 seasons) may not provide more nitrogen than one of 4 seasons.
• No legume species has performed consistently better than any other species.
• Sowing a mixture of inoculated pasture legume species that are suited to the region is important to spread the risk and ensure a good stand of legumes is achieved.
• Weed control using grazing management and/or chemical control is seen as the best way to maintain a high level of legumes in the paddock and therefore increase soil nitrogen

• Volatilisation losses were small on Mallee sandy loam at Walpeup where 4mm of rain fell two days after fertiliser application.
• Volatilisation losses from the application of urea to Wimmera clay was as high as 26 percent with small rainfall events (< 4mm) in the 20 days after application.
• Significant nitrogen losses were experienced when ammonium sulphate and liquid UAN were applied to Wimmera clay. Both products lost 12 percent of applied.

• With a soil nitrogen (N) content of 103 kg N/ha at sowing, Mace wheat yielded 3.1 t/ha with no N fertiliser applied and contained 6.6% protein.
• Optimum gross margins were recorded with 75 kg N/ha, though none of the N levels up to 100 kg N/ha reached 9% protein.
• Yield response was greatest for N application timings at sowing, GS31, or a split application between GS31 and GS39.
• A crop sensor was used to measure in season nitrogen responsiveness and was able to predict the optimal N rate.

• At Minnipa the late sown (resown due to mice damage) wheat gave a yield response to 20 units of up-front N, but not to N applied in-crop in 2010.
• At Mudamuckla there was no response to applied N above base rates on soil with adequate N content in 2010.

• At two sites, excessive application of nitrogen caused haying off of Gairdner barley in 2002.
• Increasing nitrogen application had a greater effect on quality than yield. Yield was limited by moisture not nitrogen.

• Grain yields of wheat were higher when additional nitrogen was applied at sowing compared to when applied at GS31.
• Timing of nitrogen application is essential to maximise plant growth and achieve yield potential.
• Grain protein was only higher when delayed nitrogen application was applied, which resulted in reduced wheat yield.
• Starting soil moisture, paddock rotation history and potential yield of crop are important factors to consider when deciding amount of nitrogen to apply and timing.
   

• Grain yields of wheat were higher when additional nitrogen was applied at sowing compared to when applied at GS31
• Timing of nitrogen application is essential to maximise plant growth and achieve yield potential
• Grain protein was only higher when delayed nitrogen application was applied, which resulted in reduced wheat yield
• Starting soil moisture, paddock rotation history and potential yield of crop are important factors to consider when deciding amount of nitrogen to apply and timing

For further information see Payne, RA and Ladd, JN (1993) Soil organic matter and nitrogen management in dryland cropping systems, Part II: Nitrogen requirements for dryland cereal crops. Dept Primary Industries of SA. Technical Report No. 212 (Agdex 536).

The objective of this GRDC / SPAA funded project is to increase the level of adoption of PA 'beyond guidance' by broadacre farmers. The project specifically aims to increase the level of adoption of variable rate (VR) by growers in the project to 30% by 2013.This goal will be achieved by demonstrating how to use PA tools to growers at a regional level and by increasing the skills of growers and industry in PA to a level where they can then use PA tools in their farming systems to achieve economic, environmental and social benefits. The grower mentioned the usefulness of the Greenseeker map to provide a visual overview of how the crop was growing and where nitrogen was being used. This has helped with understanding how different soil types perform and allow extraction of nitrogen during a growing season.

• Paddock variance was measured across two paddocks through EM (electromagnetic) surveys. Based on this variance, high and low EM zones were identified.
• Two small plot trials compared nitrogen (N) response in a high and low EM zone of two paddocks sown to Trojan wheat, one in Yarrawonga (sown 22 April) and the other in Dookie (sown 12 May).
• • Both paddocks had high levels of nitrogen available in the soil (120–200kg N/ha 0–60cm) irrespective of zone.
• The largest response to nitrogen (1t/ha) was observed in the high EM zone at Dookie, where the highest levels of available soil nitrogen were recorded (200kg N/ha).
• Dry matter (DM) differences and normalised difference vegetation index (NDVI) readings at the Dookie site suggested the crop canopy was responding to applied nitrogen; this indicates the crop did not benefit from the high levels of soil nitrogen present (possibly as a result of later sowing or subsoil constraints).
• At the Yarrawonga site there were no significant indications from NDVI readings that a response to nitrogen fertiliser was likely; this was supported by high grain yields in the nil nitrogen plots (5.8t/ha and 6.4t/ha in the high and low EM zone respectively).
• At the Dookie low EM site, grain protein of 11.9% in the lowest-yielding treatment suggested there was sufficient soil nitrogen available to meet crop yield and protein requirements; this contrasts with in-crop NDVI measurements, which suggested the crop would respond to applied nitrogen.
• At Yarrawonga nitrogen application strategies based on NDVI readings meant nitrogen application was
• delayed until third node (GS33) in the high EM zone, which resulted in only limited uptake. A slightly earlier second node (GS32) application in the low EM zone resulted in an excellent response (0.39t/ha)to the NDVI-based approach.

Key findings:

• This site was fairly unresponsive to nitrogen (N) application. Yield and screenings did not significantly change with increasing rates of N, but there were moderate responses in grain protein to all rates of applied N in all varieties.
• The 40 kg N/ha at sowing + 40 kg N/ha in crop treatment had a significant increase in grain protein above the 40 kg N/ha at sowing only treatment in all varieties, but was not significantly different from the 80 kg N/ha at sowing treatment

Results:

There were moderate responses in grain protein to all rates of applied N in all varieties. The 40 kg N/ha at sowing + 40 kg N/ha in-crop treatment showed a significant increase in grain protein above the 40 kg N/ha at sowing only treatment in all varieties, but was not significantly different from the 80 kg N/ha at sowing treatment. Screening levels were low, with only Dart above 5% in some treatments. Dart, being the quickest variety in this trial, flowered and reached grain filling ahead of the other varieties, most likely causing it to be filling grain and losing green leaf during the hotter and drier part of September. The slower varieties probably benefited more from the late spring rains in this season

Key mesages:

• There was a decline in yield with all rates of applied nitrogen (N), which was likely to be associated with high levels of residual soil N at the site.
• Grain protein increased with all rates of applied N in all varieties, most likely due to decreased grain size.
• Sowing time had the greatest influence on yield, with the earlier sowing time yielding close to 1 t/ha better than the later sowing time for each variety.

Conclusions:

This trial site had a high starting soil N level of 233 kg N/ha (0–120 cm) which probably contributed to declining yield with increasing rates of N application. However, protein levels still increased with increasing rates of N application, but this was most likely due to decreased grain size. Most varieties yielded almost 1 t/ha higher with TOS 1 compared with TOS 2. Sunmate and Suntop generally performed similarly at both sowing times. They were the highest yielding varieties at each sowing date, but also had lower protein achievement. Lancer and Spitfire also performed similarly at the two sowing dates and were generally lower yielding than Sunmate or Suntop at each sowing time, but obtained higher grain protein levels.

Farmers in this situation can be confident that since the NDVI and the N sensor measurements complement one another, the low producing areas can be farmed differently to the high producing areas. In order to maximise profits on farm, growers ought to consider varying inputs according to productive potential of their paddocks. Soil types vary considerably throughout the Upper North and can also be quite variable within paddocks. Considerable cost benefits can be made over time by using variable rate technology in paddocks with high variability. While the upfront costs might be large, the investment quickly pays itself off, giving farmers increased confidence in using the technology. Some training is often required when using new monitors and equipment however regular use and familiarity of products improves ease of operation.

With extremely dry conditions following both sowing on 6 June and nitrogen application, there was no response to nitrogen application in this trial, despite the low level of available soil nitrogen (52kg/ha N, 0-130cm) recorded at the start of the season. • With yields in the range of 1.3-1.6t/ha, there was no response to applied nitrogen regardless of the timing or product used. • There was no evidence to indicate that, under these conditions, liquid fertiliser (Easy N - 32% w/w (16% urea, 8% nitrate and 8% ammonium) or Green Urea 14 (an agrotain urease inhibitor coated urea) were superior to straight urea (46%N).

• In a variable trial there were no significant differences in grain yield (machine harvested) due to row spacing 500mm v 750mm (20” v 30”), plant population (85,000 v 120,000 pl/ha) or N rate 300 v 450 kg N/ha).
• Overall grain yield average in the trial was 16.47 t/ha.
• Although no yield differences were recorded it was noted that narrower row spacing produced more overall harvest biomass, particularly at the lower plant population.
• Since there were no difference in grain yield associated with narrow row spacing and lower plant population, harvest index was reduced.
• Crop canopies at harvest contained more nitrogen than was applied as fertiliser indicating that at 300 kg N/ha applied as much as 235 kg N/ha was supplied from the soil.
• Increasing N fertiliser applied from 300 to 450 kg N/ha did not result in any greater N offtake in the crop at harvest, indicating that N was either left in the soil or lost.