• Early sown, long season material did very well in 2018 considering the season (Growing Season Rainfall was one of the lowest on record).
• More options are available to growers who have the opportunity to sow wheat to coincide with earlier rain and the need to start earlier due to a large cropping program.
• The trial is planned to run again in 2019 with the aim to test earlier sowing dates than 2018. 

• Profitability and risk are driven largely by a combination of soil type, associated enterprise mix, level of debt, machinery investment and land purchases.
• There is not best best farming system. Successful farming depends on factors within each system such as labour, soil type, rainfall and skills.

• No measured improvement in phosphorus uptake through low seed bed utilisation systems.

• Deep placement of organic and inorganic amendments increased grain yield by 20–40% for three successive years on a sodic subsoil at Rand.
• Deep placement of organic and inorganic amendments increased root growth and soil water use from the deeper clay layers during the grain filling-stage.
• Improvements in grain yield with deep placement of organic and inorganic amendments were associated with reduced subsoil pH and exchangeable sodium percentage, and increased microbial activity.

Please refer to attached trial report for results and discussion.

• EM38 surveys need to be calibrated through soil testing to identify areas with subsoil constraints.
• Simulated wheat yields using historical rainfall data demonstrated the effects of soil type and subsoil limitations on potential crop yields and recharge.
• Variable rate technology for fertiliser could optimise returns for paddocks with subsoil limitations.

• The paddock utilised for the trial had a significant number of effective naturalised medic rhizobia. There was no rhizobial inoculation response.
• Total annual biomass was higher in the regenerating medic plots versus sown treatments due to earlier germination and growth of naturalised medic.
• Grazing increased overall medic production.

• The paddock contained a population of effective rhizobia and so the number of nodules on lateral and taproots was not affected by the addition of different rhizobial inoculants.
• Improved soil nutrition did not affect dry matter production and nodulation.
• Grazing (simulated) reduced the total dry matter produced by the medic pasture, however the use of sheep would provide a more realistic assessment of grazing on DM production, nodulation and N2-fixation.

• Nitrogen offtake in grain was higher with mid-row banding urea than urea broadcast and incorporated by sowing for both BeckomA nd LongReach SpitfireA at the 80, 120 and 160 rates of N application.
• Apparent fertiliser recovery in grain was also higher from mid-row banding urea than from urea broadcast and incorporated by sowing in five of the possible eight treatment comparisons.
• Soils cored at stem elongation from the mid-row banding treatment showed higher ammonium levels in the top 20 cm and lower nitrate concentration at 60–100 cm than urea broadcast and incorporated by sowing.
• Roots proliferated around and below the original mid-row banding. These results indicate potential for mid-row banding to improve N use efficiency.

• Essential plant growth requirements including nutrients and water are influenced by the capacity of the soil to both store and supply these elements.
• Infiltration of water into soil and the ability for soils to retain water are processes fundamentally important for soil productivity.
• Management strategies that increase the rate of water infiltration into soils are likely to improve the potential of the soil to capture larger amounts of water.
• The rate of movement through the soil profile however, may be more important for crop production in terms of influencing the ability of plants to utilise this water.
•  

While water volume and droplet size were the focus of this study there are further measures that can be taken by the spray operator to increase herbicide penetration in stubble. In a recent paper by Gordon (2017) some of the strategies highlighted were:

• Reducing spraying travel speeds can generally improve the penetration into stubble and improve the evenness of the application.
• Narrower nozzle spacings can also be of benefit, provided the spray quality and boom height are suitable. 
• Alternately, many operators have plumbed machines with nozzle spacings to match the crop row width. Where nozzles are positioned in the centre of the inter-row gap between standing stubble lines, the nozzle height may be lowered to obtain an overlap close to the base of the stubble. This may improve soil contact and reduce interception by the stubble, provided spraying speeds and wind speeds do not excessive.

• Varieties in this trial did not show a response to extra applied nitrogen at this site which was in pasture for the previous 3 years. Possible reasons are low rainfall and plants being water limited and/or sufficient background levels of nitrogen available for the crop in this soil type. 
• In this season results showed a benefit in seeding early, providing greater growing season and therefore yield benefit, averaging 210 kg/ha higher. 

(i) Baits do kill juvenile snails. (ii) Stubble and/or green plant material reduce uptake of snail bait by juvenile snails. (iii) A baiting program that is integrated with appropriate stubble and weed management at presowing is likely to optimise snail control. (iii) Calibrate your bait spreader to optimise the effectiveness of your baiting program. (iv) Perlka® did not have a significant effect on reducing snail populations in caged field trials. (v) The effectiveness of bait product and bait size differs between the pest snail species; once fully researched,future bait program recommendations will be tailored to the species being targeted.

• Surface applied lime increased soil pH in the top 10 cm by 0.9 unit.
• Deep application of lime had a limited impact on soil pH at depth, possibly due to sampling errors and natural soil variability.

• Lime at 3t/ha increased pasture growth in the first year after application.
• Tune in for next year’s write up to see what effect the lime placement had at depth on soil pH.

• At Streaky Bay and Cungena in 2019, establishment was similar with dry sowing or sowing at the break, and at Minnipa establishment was better with dry sowing.
• There was a yield penalty if no fertiliser had been applied at Minnipa.
• Dry sowing increased grain yield at Minnipa by 0.2 t/ha compared to waiting for the break in the season.
• Dry sowing at Streaky Bay and Cungena reduced grain yield, by 0.7 and 0.3 t/ha respectively, compared to waiting for the break and sowing into a moist soil bed.
• All three sites showed a decrease in early dry matter with dry sowing.
• The herbicides and fungicides evaluated in the trial did not impact on plant establishment when dry sowing.

• Clethodim applied at 500ml/ha to ryegrass at the 2 to 3 leaf stage averaged 84% control.
• Two early applications, ryegrass at 2 to 3 leaf and then again 3 weeks later, gave the best control of resultant ryegrass head numbers.
• All combinations of clethodim and butroxydim applied after ryegrass reached the 2 to 3 leaf stage significantly reduced grain yield.

• Most legumes favour pHCa > 5.0 to a depth of at least 20 cm; acidic layers below 5 cm adversely affect root growth, nodulation, plant vigour and N2 fixation potential of acid-sensitive pulses.
• Ineffective incorporation of lime under minimum tillage systems confines the lime effect to the shallow surface layers (0-5 cm).
• An ‘acid throttle’ located between 5 to 20 cm in the soil profile is not detected using soil samples collected at standard depths of 0-10 cm and 10-20 cm, finer sampling at 5 cm intervals is recommended to detect acidic layers.
• Apply and incorporate adequate rates of fine grade, high quality lime at least 12 months before sowing acid-sensitive species to allow time for the lime to react and increase pH to the depth of incorporation.

• There was no effect of stubble retention on canola yield because it followed chickpea and there was very little, if any, stubble of chickpea.
• There was no significant effect of gypsum application on the yield of both canola and chickpea.

Yield results in both wheat and chickpea indicate minimal if any differences between treatments; however, analysis of soils, grain and plant samples may reveal some interesting information.

• Surface application of organic matter significantly increased early growth of wheat and canola, but not lentils at Birchip.
• At anthesis, no difference existed between treatments for wheat and at maturity, conventionally sown crops out yielded all other treatments.

Surface application of organic matter significantly increased early growth of wheat and canola, but not lentils at Birchip. At anthesis, no difference existed between treatments for wheat and at maturity, conventionally sown crops out yielded all other treatments.

• The research aims to find rhizobia that will support lucerne growth on acidic soils.
• Good levels of nodulation found on acidic sand at Kingscote, despite soil acidity, pHCa 4.6
• Lucerne is highly recommended for KI soils that do not receive lengthy periods of water logging or have high levels of aluminum.
• Purchase freshly coated seed as background levels of lucerne rhizobia are low.

• With the current climate trending to decreased seasonal rainfall, each 1% increase in productivity is important.
• Increases in productivity can come from increased yield, more efficient application of inputs, or more timely grain marketing.
• Knowledge on the soil water holding properties, the time when the crop is taking up the most water from the soil and the current yield estimation models allows growers to market grain with more confidence pre harvest.
• Tools such as Yield Prophet, iPaddock Yield, soil moisture Probes and water use efficiency models are all very useful in assisting to predict grain yields with a relatively high level of confidence when accurately set up.
• In this project “iPaddock Yield” provided the greatest level of accuracy in predicting final grain yield on July 31st 2015. The simple French & Shultz “Broken Stick” model was very close to the accuracy of the ipaddock Yield at 77% & 74% accuracy.
• When there is confidence in the early to mid-season yield prediction combined with accurate soil Nitrogen testing and modeling, there is a greater chance of maximizing profits from applied nitrogen.

• The highest recorded water use efficiency (WUE) was observed at Spalding where 26.6 kg of wheat was produced per hectare for every mm of growing season rainfall.
• Growing season rainfall was below average meaning that stored summer soil moisture was very valuable in 2011.
• The WUE at Hart has been 14 kg/mm/ha or 70% calculated since 2001.

• The highest recorded water use efficiency (WUE) was observed at Spalding where 26.6 kg of wheat was produced per hectare for every mm of growing season rainfall.
• Growing season rainfall was below average meaning that stored summer soil moisture was very valuable in 2011.
• The WUE at Hart has been 14 kg/mm/ha or 70% calculated since 2001.

• At three out of the 4 sites gladius wheat sown onto a pea crop background from 2011 produced the best grain yields.
• At Condowie wheat on barley (2.54t/ha average) was always better than wheat on wheat (2.10t/ha average), regardless of extra nitrogen.

• The addition of a straw layer acted to reduce evaporation and significantly increased grain yields and water use efficiency in 2012, at 4 field sites.
• Soil evaporation also decreased with increasing light interception from larger crop canopies.

• The addition of a straw layer acted to reduce evaporation and significantly increased grain yields and water use efficiency in 2010 and 2011 at 3 field sites.
• Soil evaporation also decreased with increasing light interception from larger crop canopies.

The highest recorded WUE was observed at Spalding where 18.3 kg of wheat was produced per hectare for every mm of growing season rainfall.

• The best WUE for 2008 occured at the Tarlee site for barley, 28.5kg/mm/ha or 141%.
• Frost in August and October reduced WUE at Spalding.

• The best WUE for 2008 occured at the Tarlee site for barley, 28.5kg/mm/ha or 141%.
• Frost in August and October reduced WUE at Spalding.

• The best WUE for 2008 occured at the Tarlee site for barley, 28.5kg/mm/ha or 141%.
• Frost in August and October reduced WUE at Spalding.

• The best WUE for 2008 occured at the Tarlee site for barley, 28.5kg/mm/ha or 141%.
• Frost in August and October reduced WUE at Spalding.

WUE was generally low at the 4 sites in 2009, ranging from 9.1 kg wheat/mm/ha at Tarlee to 12.2 kg wheat/mm/ha at Spalding.

• Pasture legumes are suited to crop rotations, even short 1:1 rotations.
• Pasture legumes can improve the grain yield and protein content of subsequent crops.
• Pasture legumes appear to provide an advantage to the subsequent crops not provided by fertiliser N (50 kg/ha).
• Pasture legumes regenerate well in the year following a crop.
• Reasonable yields can be obtained from spring sowing of wheat. 
   

• The pasture-crop rotation system has so far been successfully established in these sites, with the pasture plant productivity improved year by year.
• For further discussion and conclusions from this work please see the attached trial report.

• This three year research project aims to increase the yield and reliability of field pea under water deficit and is a major pre-breeding target of Pulse Breeding Australia.
• Key traits being monitored include phenology, canopy and yield traits and the adaptive value of these traits will be explored.
• The trade-offs between adaptation to stress and yield in good environments will be investigated.
• Improving the reliability of yield of field pea in water limiting environments will help to provide a robust break crop option for growers in low rainfall regions.
• Preliminary results from the second season and summary of first season experiments are presented with more detailed trait data currently being analysed, with one more year to follow.
• Correlations between yield and canopy traits such as greenness and growth rate have been identified.
• We have also used APSIM to model the seasonal soil moisture stress for all environments.

• This three year reserch project aims to increase the yield and reliability of field pea under water deficit and is a major pre-breeding target of Pulse Breeding Australia.
• Key traits being monitored include phenology, canopy and yield traits and the adaptive value of these traits will be explored.
• The trade-offs between adaptation to stress and yield in good environments will be investigated.
• Improving the reliability of yield of field pea in water limiting environments will help to provide a robust break crop option for growers in low rainfall regions.
• Preliminary results only from the first season of experiments are presented with more detailed trait data currently being analysed, with two more years from different seasons to follow.
• Correlations between yield and canopy traits such as greenness have been identified.

A trial was established west of Moora in 2016 to investigate in season potassium response in barley. The main objective was to compare Lokomotive, a liquid potassium product, to the more commonly used granular muriate of potash (MoP).  Both soil and plant sample analysis showed the site to be marginal/deficient in potassium. Treatments were applied at GS 32. This timing was chosen as potassium deficiency is most commonly identified late in the growing season, when visual symptoms appear, and confidence in an economic response to applications of MoP in the current season is diminishing. At the time of application there were typical potassium leaf deficiency symptoms on the lower leaves. 

Good growing conditions were experienced in Moora in 2016 and resulted in high barley yields of 4.17 to 4.39 t/ha. There was a small yield response (1.7% to 5.3%) from both Lokomotive and MoP however this was not significantly different to the untreated control. The small response to potassium in 2016 may be attributed to the wet spring conditions that would have made potassium in the soil more available to the crop. Further evaluation of in season potassium application is required when spring conditions aren’t as favorable as 2016.  

 

 

• As a result of very poor seasonal conditions, there was no response to nitrogen applied to Yitpi wheat at either Rupanyup or Hopetoun in 2006, despite very low soil nitrogen levels.
• Delaying nitrogen application until after the end of tillering can allow a more accurate assessment of seasonal conditions to be made and money to be spent on nitrogen only if a response is likely.

Climate variability or climate change? Whatever the situation we face we need to be prepared to respond quickly to temperature and rainfall extremes with better in-crop management decisions.

Climate variability is something we have to learn to live with, and we need to manage it better. Be prepared to learn more about the impact of increasing variability in temperature and rainfall on the bottom line of your farm.

• There was very little disease pressure at this particular demonstraiton site.
• This trial should be repeated under a number of different conditions with varying disease pressure to get a better understanding of the true value of fungicides in low rainfall areas.

• Electromagnetic (EM) zoning was strongly related to differences in pH at 10–30cm depth in two out of three paddocks.
• All three paddocks showed variability in chemical properties, with the EM zoning showing good separation of chemical properties between zones. This provides confidence that the zoning was suitable.
• Variability in plant growth needs to be examined ‘holistically’ rather than just focussing on one variable. While a paddock may show variation in plant available water (PAW), it may be that sodicity or subsoil acidity is the key limiter in plant performance, not water availability per se.
• Existing precision agriculture (PA) datasets, in conjunction with selected chemistry sampling, can be used to indicate relative change in PAW across paddocks, but not the actual volume of water storage.

There was a small discernable response in early season biomass to N applied at seeding at the sampling on 29 August August.

• Yield differences between soil types were less than seen in previous seasons on this paddock.
• Yield responded to an extra 25kg/ha N at sowing on the deep yellow sand over gravel and shallow gravel yielded around 2.5t/ha.

• Yield differences between soil types were less than seen in previous seasons on this paddock, although they did yield in expected order.
• Starting nitrogen levels were quite high (>100kg N/ha) due to previous crop history.
• Overall with the better responses to applied N being achieved on the better soils or where there was plenty of starting soil nitrogen, this experiment has given encouragement to the idea of managing soil types (or management zones) differentially for N.

For a discussion of results and take home messages from this trial please see the attached trial report.

• For discussion please see the attached trial report.
• A full report will be written when protein & quality analyses are complete. 
   

For a full list of results of plant measurements, application of nitrogen treatments, yield, protein and quality data please see the attached trial report.

RESEARCH QUESTION

Can incorporation of lime economically remediate a subsoil acidity constraint on gravel soils?

RESEARCH OBJECTIVES

• To evaluate four rates of lime
• To compare three methods of incorporating lime
• To investigate an optimal combination of application rate and method of incorporation for ameliorating soil acidity

 

BACKGROUND SUMMARY

Forest gravel soils are common in the medium to high rainfall zone of Southern Western Australia and are estimated to account for about 2.4 million hectares of the state's farming area.  Non-wetting and soil acidity issues are known to constrain the productivity of these soil types, which are common throughout the Southern DIRT region. Considering this, limited local research has been conducted in regards to the effects of incorporating lime as a method to alleviate these soil constraints more effectively and economically than the traditional method of top-dressing.

The trial was collaboratively designed by Southern DIRT R&D committee members and staff, Wes Lefroy of Precision SoilTech, and the landholders, Roger and Simon House.  The focus of the treatments was to;

a)  Utilise the most economic source of lime for the landowners,

b)  apply the lime at a range of rates representative of both local practice and industry endorsed practice, and

c)  incorporate the lime with equipment which are known to improve the movement of lime through the soil profile compared to top-dressing; while having minimal complicating factors (i.e. poor seed placement) which are commonly associated with other forms of deep tillage.

The trial is located 12 km north of Kojonup and was chosen for its combination of targeted soil type (forest gravel) and pH range (4.5 – 4.8 CaCl2) up to a depth of 60cm.

 

 

The methods for incorporating lime in the trial are offset discs and one way plough, with knife-points at seeding included as a control.  Both offset discs and one way ploughs are generally used for the shallow incorporation of lime, and in this trial the depth achieved was approximately 10cm for the offset discs and 12cm for the one way plough. Research has shown that these incorporation methods can be more effective than the standard practice of top-dressing lime at increasing soil pH at depth by mixing lime into the soil profile when adequate rates are applied. While the lime is mixed well to the working depth of the implements, neither of these methods have the capacity to incorporate lime to depths beyond 20 cm.

Both offset discs and one way ploughs are considered by local growers as more cost-effective options for incorporating lime when compared to other methods (i.e. rotary spading). Annual plot soil testing and harvest yield will be the primary indicators used to assess how quickly and effectively the various treatments are able to raise pH at depth and increase production on forest gravel soils constrained by subsoil acidity.

Prior to seeding the trial in 2015, the site was extensively soil sampled to a 60 cm depth by Precision SoilTech.  An area with the capacity to accommodate the treatments with minimal variation in soil pH between plots was identified, however due to the nature of this site and the layout of the treatments (designed to be practical for the landowner to implement and maintain), there are inconsistencies within the trial which need to be carefully considered when assessing treatment effects. There were no systematic differences between the lime treatments in crop establishment and harvest yield, seemingly as a result of variability in soil pH and other characteristics between plots, complicated further by the layout of the trial, rather than a treatment effect.

It was observed that incorporation by both offset discs and one way plough did not reduced or cause uneven germination compared to knife-point at seeding, and during the season it was not visually evident that incorporation treatments had a major effect on crop growth and health compared to the control treatment.

While it may not be expected that shallow incorporation of lime would result in significant differences between lime treatments on a forest gravel soil type in the first year of a trial, it is imperative going forward into the next two seasons that a professional statistician helps analyse current and future data to ensure that subsequent interpretations can be improved, given the apparent impacts of site variability, and as treatment effects may become more pronounced.  It is expected that the ongoing plot soil testing conducted prior seeding each season will be the primary indicator used to determine whether incorporation of lime using either offset discs or one way plough can reduce soil acidity on a forest gravel at depth more quickly than the district practice of top-dressing, while yield responses will determine any economic benefits.

EverCrop research reported in this and previous Crop Updates (2010-2014) has built up a sound knowledge base on the viability, performance and economics of pasture cropping and companion annual legume based systems for fragile soils in the Northern Agricultural Region that are marginal for continuous cropping. Collectively, trials at Mingenew and Dandaragan over the past two seasons (2013 & 2014) have demonstrated that subtropical perennial grass pastures lift the overall productivity of deep sandy soils, extend the period of available green feed, convert summer rainfall into feed, reduce the winter and summer weed burden, and increase ground cover.

Mackellar wheat was cut at early‐mid stem elongation (GS32‐33), considered too late to be grazed without affecting grain yield, to determine effects under irrigation. Dry matter production was 22% higher compared with an earlier cut at GS30‐31 (start of elongation). With adequate soil moisture the late cut plots recovered well and grain yield was only 3% lower and not significantly different to the
earlier cut plots. Extended grazing of dual purpose wheat coupled with capacity to irrigate therefore provides increased economic and management flexibility.

These experiments provide a framework to allow growers in the Wimmera and Southern Mallee to use soil tests for nitrate N, organic carbon, and soil water to determine firstly, their yield potential, and secondly, whether there is a need for nitrogen fertiliser to achieve that potential.

• The trial was confounded by a severe shortage of plant available water (e.g. very low rainfall) and severe sub-soil acidity that resulted in toxic levels of plant aluminum concentrations that impacted negatively on crop productivity.
• The treatments (excluding prilled humate, which produced negative crop impacts) should be repeated (with VAM) at a site with more even sub-soil conditions. CALCIPRILL and VAM seed dressing showed particular potential for quality grain production and MAGPRILL showed particular potential as an effect agent for increasing soil pH.

• EM38 successfully mapped differences in soil water properties across the paddock.
• Positive response to fertiliser in wheat on wheat and higher yielding season.
• Barley yield decreased with increasing rates of nitrogen and phosphorus fertiliser.

• EM38 successfully mapped differences in soil water properties across the paddock.
• There were no significant yield increases from increased fertiliser.
• Reducing fertiliser on heavy soils had no negative impact on yield.

The main agronomic issues to be assessed in 2012 are:

• Targeting of seeding and post seeding nitrogen applications in line with identified changes in soil water characteristics ie changes in the ‘bucket’
• Assessment of gypsum applications over soil zones identified as having variations in sodicity levels. A trial has already been implemented which will allow economic assessment for several years.
• Sound agronomic and economic phosphorus fertiliser management in line with changes in productive capacity of soil zones and responsiveness of soil types to phosphorus applications.

• The goal of achieving a 10% increase in water use efficiency appears to have been achieved quite comfortably as evidenced by the entry and exit survey results.
• Farmers in the Upper North district have madesubstantial gains in knowledge, skills and practice change to increase their water use efficiency.

• No yield differences were observed between the incorporated stubble and the standing stubble plots despite differences being recorded in plant growth during the year.
• The dry spring conditions had an impact on grain yields with no significant difference observed between treatments. 

• Yield differences were observed between the incorporated stubble and standing stubble plots.
• The hot dry conditions during November had a major impact on grain yield.
• Lodging was a problem in all of the plots with the incorporated plots particularly affected.
• At this stage no significat tincrease in soil orgainic carbon was observed.

• To justify the use of late-applied nitrogen(N), a premium for H2 wheat (almost $60/t over ASW) was required in 2011.
• UAN still increased protein despite rainfall 15 days after application.
• 2011 highlighted the need to apply N during tillering to promote biomass and encouraging greater yield potential.

• Gibberellic acid is a safe, cheap and convenient way to increase winter fed growth, but it must be applied early in the season (ideally by late autumn/early winter).
• Applying early in the season will boost winter growth.
• Applying too late can potentially cause a decrease in spring feed production.
• Don’t graze the paddock within 3 weeks of application.

• The rotation with canola as a single break crop (canola– wheat–wheat rotation) had the highest average gross margin ($529/year) across three years.
• The profit/cost ratio was the highest when canola was used as a single break crop (2:8) and the lowest for all brown manure treatments as well as continuous cereal without nitrogen input.

The complex nature of these trials has generated a vast array of information. To best extract meaningful results it is necessary to pry apart the data to generate answers addressing the key facets of the hypothesis: see attached report for full details and discusison.

• Organic carbon accumulation in soil did not approach an upper limit.
• Increases in organic carbon accumulation were due to accumulated microbial detritus (i.e. dead microorganisms and microbial products).
• Soil with the lowest organic carbon concentration at the start of the experiment accumulated the greatest mass of stable organic carbon.
• Nutrients applied based on humus nutrient ratios promoted organic carbon stabilisation in soil.

• Oats demonstrated the greatest variation in ME between samples, with values ranging from 12.8 to 13.9 MJ ME/ kg DM.
• Due to the greater variation in ME for oats than other cereal grains, testing to determine nutritive values is recommended.
• Average ME at 13.6 MJ ME/ kg DM and protein at 13.2% were high for cereal grains and appeared to be consistent across varieties and between sites.

• Compass, Fathom and Scope CL were good competitors with weeds, which is consistent with previous years’ findings.
• Hindmarsh and Spartacus CL are poor weed competitors.
• The advantage of sowing earlier in order to increase crop competition failed to improve the competitiveness of La Trobe given the high spring rainfall.

The risk of stem frost damage can be minimised by using winter wheats if sowing prior to 20 April. Spring wheats should be kept within 5-7 days of their optimal sow date. If appropriate, risk of BYDV should be managed by backing up imidacloprid seed dressing with foliar insecticides at the start of tillering if aphids are present. New winter wheat cultivars are in the pipeline and are likely to have significant yield advantages over current ageing material.

• Managed bee hives have the ability to substantially increase bean crop yields.
• Across the 12 bean trials there was an average of 54% yield increase over the exclusion tent.
• In trials with adequate introduced bee densities an average of 73% yield increase was achieved over the exclusion tent.

Stripe rust indicator plots were sown at three BCG trial sites - Sea Lake, Birchip and Marnoo. Seven varieties with different disease resistance levels, ranging from Very Susceptible (VS) to Resistant (R), were sown. These plots served as an excellent tool to observe when stripe rust establishes in an area, what impact a single application of fungicide had on the disease level and also, very importantly, whether the established rust resistance ratings were holding true for each of the varieties. T

 Indigo 76 microbial seed treatment was applied @ 3mL/1000kg seed one day prior to planting. There was no significant impact on establishment, NDVI (~crop biomass) or grain yield across the four crop types evaluated. There was however a significant reduction in grain screenings in Indigo treated plots with a reduction in average screenings from 5.6% to 4.9%.The level of impact did not made any difference in the receival grade for any crop. There was no significant difference in barley retention but a clear trend to increased retention when Indigo was applied. Retention increased from 59 to 62%. No change in grain quality was obtained in this situation. In this trial, the application of Indigo 76 microbial seed treatment did not achieve a significant impact on yield or quality grade when applied to wheat, barley, durum or chickpea seed.

• The Kerang site had a Potassium (K) soil level (0-10cm) that exceeded 600 ppm (Colwell K) at sowing and showed no yield response to additional K applied in crop.
• As was the case at Yenda the application of K as potassium sulphate at V4 or V8 saw no change in leaf tissue levels when compared to the control (no added K) assessed at V10 or tasselling.
• Harvest results showed no response to added potassium, indicating that the soil was able to supply the required potassium to the crop.
• There was no evidence of luxury uptake of K in tissue and grain samples (assessed in untreated, 40 (tissue only) and 80 kg /ha K).

• The Yenda site had a Potassium (K) soil level (0-10cm) that exceeded 500 ppm (Colwell K) at sowing and showed no yield response to additional K applied post sowing in crop.
• Application of K as potassium sulphate at V4 and or V8 saw no change in leaf tissue levels when compared to the control (no added K) when tissues were assessed at V8 or tasselling.
• Harvest results showed no response to added potassium, indicating that the soil was able to supply the required potassium to the crop.
• There was no evidence of luxury uptake of K in tissue and grain samples (assessed in untreated and 80 kg /ha K).

• Plant growth regulator (PGR) application at the recommended time of early stem elongation (Z31) did not alter root or shoot growth in the barley cultivar (cv) CompassA.
•  When PGRs were applied during early growth stages (Z12–13) root growth was inhibited or unchanged depending on the active ingredient applied and the application method.
•  When PGRs were applied early and when applied as a soil drench they inhibited root growth, but when applied at the recommended time for controlling stem height, PGRs had no effect on root
growth.

• Plant growth regulators (PGRs) had minimal effects on the plant height of different barley varieties.
• PGRs reduced some lodging, however, this occurred predominantly in the taller cultivar (cv) prone to lodging (cv. CompassA).
• Neither PGR nor nitrogen (N) application increased grain yield.
• PGRs should be strategically applied, taking into account the interaction between cultivar, seasonalconditions, and application timing.

• However, the influence of seedbed N application (50kg/ha N) was evident in the crop structure scores, producing 150-200 more shoots/m2 and producing higher readings when the crop sensor Greenseeker® was passed over the trial than the GS30 stem elongation timing or the zero nitrogen controls.
• Despite a relatively low soil nitrogen reserve at sowing (43 kg/ha N 0-100cm), there was no influence of nitrogen on yield.
• In a trial subject to low levels of spot form of net blotch (SFNB), there was no response to fungicide over the untreated.

The work illustrated that in low fertility situations, which are more ideal for malting barley (2nd cereal low soil N reserves), there was no disadvantage to applying nitrogen applications at stem elongation (GS30-33).

• There is no evidence to support growers grading seed into different size categories and sowing the smaller seed.
• In one trial in 2015, sowing seed of different size classes did not significantly influence the yield of PBA NasmaA. Insufficient data is currently available to make a recommendation either way on this practice, but there was a trend towards reduced size of harvested seed and yield from sowing smaller PBA NasmaA seed.

• Pre-emergent herbicides can cause crop damage. Separation of the herbicide from crop seed is essential for crop safety, which is more easily achieved in knife-point & press wheel seeding systems but considerably more difficult with low soil disturbance single discs.
• Crop stubble can intercept & bind pre-emergent herbicides, which affects crop safety & herbicide efficacy. Low solubility herbicides such as trifluralin have a tendency to bind strongly to crop residues, which reduces the potential for crop damage but also limits its ability to provide effective weed control in situations with heavy stubble load.
• Choose the right herbicide for the job – not all pre-emergent herbicides behave the same so follow label recommendations closely.

• The highest grain yields in 2017 were obtained from the first sowing date.

• In 2017, frost and rainfall had a significant influence on grain yield responses to sowing date.

• Seasonal conditions altered expected phenology responses of genotypes in 2017.

• The 2019 dry spring conditions affected genotype performance, influencing flowering time and grain yield responses.
• Current varieties were not broadly adapted across sowing dates from mid April to late May.
• Highest grain yields were achieved across phenology types in response to sowing dates, with very slow spring types maximising yield from the mid April sowing date (SD), with later sowing dates favouring faster developing spring genotypes, which achieved the highest grain yields in 2019.

• Frost significantly influenced flowering date and grain yield in 2017.

• High grain yields can be achieved from a range of genotype × sowing date combinations.

• Whilst flowering time is important in maximising grain yield potential, timing pre-flowering phases was also found to significantly influence grain yield.
 

• Crop yields declined by an average of 31kg/ha/day when sowing was delayed from 20 May to 2 June.
• There was not any significant interactions between varieties in their response to delayed sowing time from 20 May to 15 June.
• The varieties Bunnu, EGA Bonnie Rock, Espada, Fang, Lincoln and Yandanooka produced screenings greater than 5% when sown in mid June. 

• Crop yields declined by an average of 31 kg/ha/day when sowing was delayed from the 20th May to the 2nd June.
• Delaying seeding from 2nd June to the 15th June resulted in an average yields decline of 45 kg/ha/day.
• There were not any significant interactions between varieties in their response to delayed sowing time from 20th May to the 15th June. -
• The top performing AH/APW varieties were Carnamah, EGA Bonnie Rock, Espada, Katana, King Rock, Mace, Scout, Wyalkatchem and Zippy. Screenings of these varieties was less than 5% at each sowing time.
• The varieties Binnu, EGA Bonnie Rock, Espada, Fang, Lincoln and Yandanooka produced screenings greater than 5% when sown in mid June.

Take Home Messages

Whilst the trial didn’t go according to plan there were still some key messages that arose:

• Maximising seed-soil contact is the aim at sowing especially for the larger seeds that require more moisture to imbibe and germinate compared to small seeds.

• Unseasonably low June rainfall hindered establishment of partially sown beans due to a drying topsoil. These may have been

OK under normal June rainfall conditions.

• Hair pinning can be a serious issue when using a disc seeder especially when sowing into wet/ moist lodged stubble.

• Solutions to avoid hair pinning – sow when stubble is dry (good in theory), keep stubble standing, use sharp discs and ensure bar

has sufficient down force to cut through tough stubble.

• The effects of zinc supply in subsoil were examined in three genotypes of Brassica napus in a glasshouse experiment.
• The topsoil was supplied with zinc in all treatments whereas zinc was either supplied or omitted from the subsoil.
• Supplying zinc to subsoil significantly increased the root growth in the lower zone, markedly decreased the number of aborted and unfilled pods/plant, number of seeds/pod, individual seed weight and overall seed yield.
• Subsoil zinc also significantly increased the zinc concentration and zinc content of seed and improved the ratio of zinc uptake by seed to total zinc uptake by seed and shoots.

• Temperature did not influence extractable copper consistently.
• The effects of varied with the soil and on whether or not copper was added.
• When soils were incubated under a fluctuating temperature 20 to 40% less copper was extracted by EDTA then when incubation was constant at 20°.
• This result emphasises the need for caution in applying the results from constant temperature to field situations where the temperature fluctuates.