With pasture growing in a dry spring, not accessing stored water and producing little biomass, the effect on soil water/nitrogen and on the following crop is minimal. Prioritise paddocks which need medic seed set for retaining as pastures, but terminate more pastures later if feed is an issue. In a year when pasture is growing fast and using water and possibly fixing nitrogen, the trade-off may not be so flat (or simple) and will depend more on the following season (unpredictable).

• Over the last four years, trafficking at any level has not decreased crop production on a heavy Minnipa soil so moving to controlled traffic farming on this soil type is not likely to increase crop production due to less trafficking in the paddock.
• Trafficking on a deep sand (trial at Loxton in the northern mallee) has substantially reduced crop production for at least 4 years so CTF may have additional benefits on deep sands, especially if ripping is used to correct existing compaction.
• Similar to many previous trials, ripping has not benefited production on the heavy Minnipa soil.

• The industry should begin to work with specialist organisations such as the Australian Institute of Company Directors (AICD) and Family Business Australia to provide regionally available training.
• • Continue to develop information sheets and meeting templates that provide support to farm businesses establishing an advisory board.

• Treated seed treatment had a marginally higher yield (3.24t/ha versus 3.15), lower screenings, lower protein and higher income by $9/ha.
• Seed from control plots (untreated seed sown) had higher nutrient (Mn, Cu, Zn, P and S) concentrations.
• Coating seed does no harm but farmers need to judge what is ' best bang for their buck'.

Before attempting subsurface lime incorporation it is essential that the pH of the profile be known. The amelioration treatments were no larger than the effect of the ripping. 

• Tonic plantain and Grouse chicory are worth considering as summer forages, with the Tonic plantain likely to persist through the following winter and longer. Although not tried, Italian ryegrass (or perennial ryegrass) could be oversown for more winter feed. In this trial, winter feed production from Tonic plantain and sub clover was excellent, no doubt partially due to the high sub clover seed reserves and partially due to the high soil fertility on Tremaine’s.
• Banquet tetraploid hybrid perennial ryegrass could be considered for a medium term high quality pasture for finishing lambs/weaners in high fertility paddocks, with controlled rotational grazing over summer.

Over the 1990’s the most profitable farming system for each region was determined by losses in poor years rather than the profits in good years. Businesses with high costs associated with intensive cropping and high inputs, were impacted more by losses than businesses with moderate adoption of new crop types and moderate inputs.

• Wheat yields were significantly reduced by competition from barley and brome grass.
• The use of knockdown post sowing but pre-emergent provided excellent control of the grass weeds, which translated into a yield benefit.
• The trends in control of grass weeds and yield benefits in barley were similar to the results seen in wheat.

• Occurrence of blackleg infection was generally low at Westmere in 2013.
• The ‘Rolls Royce’ treatment of Jockey seed treatment, Impact on fertiliser and two applications of Prosaro yielded significantly higher than the control (600 kg/ha difference).
• All treatments that received foliar applied Prosaro had significantly less infection at green bud compared to only seed or fertiliser fungicide or nothing.
• Prosaro’s ability to control blackleg is clear however yield results in a year with low blackleg burden make it difficult to distinguish between in furrow and foliar fungicide control.
   

For a list of variety information and results please see the attached trial report.

A thorough understanding of trifluralin application techniques can be the difference between poor and excellent ryegrass control. It can also help achieve target plant establishment. This demonstration showed an increase in ryegrass control when up to 3L/ha trifluralin was applied. Rates above 3L/ha trifluralin did not result in additional ryegrass control. The influence of water rates was minimal due to the lack of stubble residue which shows that water rates of 50L/ha are acceptable in situations where there is very little residue from the previous crop.

• An unusual result with Silverstar out-yielding both Frame and Schooner. Previous trial work showed that Silverstar is especially sensitive to trifluralin even at recommended rates.
• Frame seedling establishment was significantly lower at the 2.4L/ha rate than at the registered rate of  Silverstar and Schooner.
• Trifluralin in not registered on wheat at rates higher than 1.0L/ha.

Frame is more tolerant to high rates of trifluralin compared to Goldmark and Silverstar.

• Triticale is very responsive to high inputs of seed and fertiliser.
• Adequate fertiliser is needed to achieve protein levels above 10%.
• In dry springs triticale yields are 10-15% below wheat, due to triticale’s longer grain filling period.

• At Streatham, no variety was significantly higher yielding than Currency, however at Hamilton, both Credit 1 and Everist were superior in yield. 
• It would appear that no Triticale variety has any better frost tolerance than any other variety and that susceptibility or otherwise to frost is mainly governed by when flowering occurs relative to the timing of the frost. Any variety which flowers when there is a frost will be badly affected. Many varieties with poor yield were badly frosted. 

• Tahara is one of the most widely grown Triticale variety in the district, however its performance was significantly inferior to that of Treat and Credit, two more recently released lines.
• For further conclusions, please see the attached trial report.

• All triticale varieties evaluated showed some degree of susceptibility to stripe rust with Breakwell being the most susceptible. Grain yield rankings largely reflect this with Breakwell finishing a distant last.
• Hawkeye was significantly higher yielding than all other varieties and this was probably assisted by significantly less lodging compared with the other varieties except Blackwell.
• Further trials will be conducted in 2009-10 to evaluate the performance of Hawkeye and screen for new disease resistant material from other breeding programs.

• The variety with the highest yield was Crackerjack at 7.35 t/ha.
• The site mean was 7.13 t/ha.

• Grain yields were affected by water-logging. Endeavour and Hawkeye were the top yielding varieties (5.0 and 4.7 t/ha respectively) but only Endeavour was significantly higher than Tahara. Endeavour has also yielded reasonable well in dual purpose trials but overall is yet to prove a worthy replacement for Breakwell.
• Yields of the new entries, Bogong and Yukuri, were dissapointing as they tended to be lower yielding than Tahara.
• Only Endeavour and Yukuri proved fully resistant to stripe rust although the other varieties remained moderately resistant.

• Over the last 5 years later maturing lines (flowering mid-November) have generally significantly out-yielded Tahara. The exception was 2000/01 where Tahara was 10-25% higher yielding than nearly all other lines due to both the absence of frost damage and the sharp finish to the season. With this season's good spring rains Tahara was back at the bottom of the pile at Symmons Plains and less dominant at Riccarton. However the fact that this year the later lines were not the highest yielding in such a favourable season suggests that the main advantage of these lines is through avoiding frost damage at flowering. 
• For further conclusions please see the attached trial report.

• Triticale yields were surprisingly good at Symmons Plains being on average higher than all except the best wheats. In contract at Riccarton the wheats tended to be higher yielding possibly due to a small amount of frost damage in the triticale. 
• It has been difficult to select a new triticale variety that is consistently higher yielding than Tahara. This appears to be complicated by greater variety x site as well as variety x year interaction in comparison with wheat trials. The front runners after several years of trials appear to be Wig, W47, Treat, Tickit and AT509. 
   

• Sow varieties inside their recommended window.
• Triticale may have a niche in the eastern areas of Central West NSW.
• Triticale is less tolerant of moistures at flowering than wheats.
• Delivery points and markets are a major influence on triticale production.

• Winter habit canola has been successfully sown in spring, grazed over summer and harvested for grain in 2012, 2013 and 2014.
• Establishing canola in spring means larger, more resilient plants in autumn with less impact from slugs and waterlogging.
• Forage value comparable to commercially available dedicated forage rapes over summer and autumn with added benefit of oil seed production.
• Grazing management and timing of stock removal is proving to have an impact on grain yield.
• Vernalisation means winter wheats have the potential to be used in the same way.
   

• Winter habit canola has been successfully sown in spring, grazed over summer and harvested for grain in 2012, 2013 and 2014.
• Establishing canola in spring means larger, more resilient plants in autumn with less impact from slugs and waterlogging.
• Forage value comparable to commercially available dedicated forage rapes over summer and autumn with added benefit of oil seed production.
• Grazing management and timing of stock removal is proving to have an impact on grain yield.
• Vernalisation means winter wheats have the potential to be used in the same way.
   

• N demand by crops in last year’s trials results was low due to the very dry finish to the season.
• There was no benefit from applying Twin N to wheat in this season.

• There was a significant step up in 2013 wheat yields from rotations which included a one year break previously compared to where there had been a two year break.
• The break crop benefit of a one year break may only last one season if grass weeds are a significant factor.
• Large break crop benefits of 0.5-1.25 t/ha were achieved following a two year non-cereal break phase compared to continuous wheat.
• The benefit of a two year break had little to do with the phases chosen for those two breaks.
• The eight most profitable crop sequences over a three year period in this trial had two year breaks in them.

This project has demonstrated that diversified cropping sequences have an important role to play in low rainfall Mallee farming systems. Including 1- and 2-year break phases were shown to significantly increase the productivity of subsequent wheat crops.

Following this year's trials results we are confident that UAN can have a role as an in-crop N fertiliser.

Best practice for using UAN at rates of up to 60L/ha when mixed with herbicides and fungicides:

• if using herbicides or fungicides not in this trial then always to a 'jar' test first for determining the physical compatibility: if white clouds or clear divisions appear, then the two may not be compatible;
• herbicides and fungicides mix better with UAN if mixed in water first;
• do not spray at temperatures over 25degrees C especially after flag leaf emergence because you don't want to scorch the flag leaf (!)
• do not spray when the Delta T is < 2, it appears that the leaf scorch is worst when humidity levels are high.

Results indicate that Uniform significantly improved crop yields in a second-year barley crop and in a wet season; in dry years’ root diseases such as rhizoctonia generally have even greater effects on grain yield and quality.

• There was significant rain in early April.
• The paddock was cultivated wet at the time of seeding.
• Seeding was delayed due to seed supply problem.

Field observation suggests the 50% UAN solution produced a better stubble cutting action than water alone.

This site presents a relatively easy population to control as seen by the lower degree of resistance to Group I (RR) and Group F (RR) and no obvious indications of ‘stacking’. The standard full rates of FC, FI, FCI, HC and HI all performed well. The population fits RRD Stage 3 where screening data indicates there are no recommended MOA limitations for either the first or second spray operations. While the options available for the first spray are many and varied there is a concern regarding the effectiveness of a phenoxy in the second spray given the level of tolerance noted to Group I, and thus the recommendation is that both sprays be multiple MOA co-mixes.

A network of soil moisture probes and Yield Prophet sites has been established across the Esperance, Albany, Kwinana East and Kwinana West port zones with the aim of providing public access to real-time soil moisture and weather data and periodic Yield Prophet reports to aid in-crop decision making, with particular reference to top-up nitrogen decisions.

Growers and agronomists have commented that the sites provided useful supporting information when making top-up nitrogen decisions, with the soil moisture probes providing additional confidence in the model’s output. Continuation of the Yield Prophet sites and soil moisture data recording and analysis will continue in 2015 across the Esperance/Albany and Kwinana East port zones, with the aim of further refining the sites to improve their accuracy and providing access to Yield Prophet and soil moisture information in a more user-friendly format.

• The 2015 season was cooler than 2014 which affected how canola varieties developed and grain yields.
• Early sowing presents a good opportunity to improve canola water use efficiency and yields but variety selection is important.

Problems potentially identified by maps include:

• nutrient deficiencies,
• in crop weeds, and 
• root disease.

At a basic level, simply overlaying in season aerial photography with yield data can provide some insight into
potential problems:

• If yield deficiencies correlate with high growth areas, then weeds could be the issue.
• Root diseases can show patterns of growth that are particular to that problem.
• With aerial photography or  a NDVI, it may be possible to see colour differences that may indicate areas of nutrient deficiency and ground truth work is crucial to confirm suspicions.

Spading alone and the addition of more clay did not appear to increase growth in this year. This would suggest that non-wetting and soil compaction were not major constraints affecting this site. The incorporation of organic matter combined with clay did, however, provide large increases to both dry matter and yield. The incorporation of organic matter provides a large nutrient benefit, particularly nitrogen, phosphorus and potassium. However, nutrients applied by the landholder should have been adequate to meet the yields delivered. Clay addition would have provided more than enough potassium.

(i) An outbreak of sclerotinia stem rot is highly dependent on the season. Prolonged wet or humid conditions during flowering favour the disease. (ii) Consider past outbreaks of the disease as a guide to potential yield loss. (iii) Avoid growing canola in paddocks with a history of sclerotinia stem rot over the past four years, or in adjacent paddocks. (iv) Well-timed fungicide treatments – when canola crops are at 20 to 30 per cent flowering stage – can be highly effective in reducing the level of infection.

Growers and their advisers in the area are more familiar with soil water relations, N dynamics and variation of yield potential in relation to soil types and season. Their integration into Yield Prophet reports has been demonstrated. This should lead to some commercial adoption of Yield Prophet and other crop decision support systems for better management of crops leading to increased profitability through management of seasonal risk.

Inversion ploughing of water repellent sands can significantly reduce repellence and increase critical components of grain yield.

Deep ripping in the presence of problem background ryegrass can stimulate ryegrass emergence and worsen weed competition with the crop.

The strength of the subsoil resource (i.e. clay component) appears important in sustaining the crop production potential and realisation of grain yield improvement.

• Barley leaf rust (LR) was observed on barley regrowth in the lower Great Southern and South Coast of WA in the summer/autumn of 2016. This contributed to the first observations of infected barley crops in the region in July 2016. All barley varieties including those with Adult Plant Resistance (APR) were under severe disease pressure and responded to application of fungicide.
• The high levels of LR in 2016 and the possibility of barley regrowth in autumn 2017 means a significant LR risk for the 2017 season and fungicide programs for APR varieties should be considered.
• LR is a social disease and all growers should be proactive in eliminating the volunteer barley green bridge. To minimise early onset of LR, the regrowth barley should be eliminated at least 4 weeks before seeding.
• Star of Bethlehem (an alternate host) should be sprayed to eliminate the likelihood of new pathotype developing in the region.
• Selecting varieties with adult plant resistance genes will reduce grain yield loss. However, performance of these varieties against LR is influenced by seasonal weather, time of disease onset, crop agronomy, and is hard to predict season to season. Depending on the LR pressure in the crop they may need early foliar fungicide intervention to reduce development of disease on plants during the growing season.
• Oxford possess two partial resistance genes (Rph20 and Rph24), and under high LR pressure application of foliar fungicides increased yield up to 64 per cent.

• In the fourth trial season lentil grain yield benefits were observed from spading and lime treatments. Addition of lime (2200 kg/ha or 6600 kg/ha) and mixing with low, medium or high uniformity were the highest yielding treatments ranging from 3.36 to 3.69 t/ha.
• Lime rate and spading have had variable response on NDVI across four years. 
• In the first three years of the trial plant establishment has generally not been affected by lime rate, spading uniformity or deep ripping.
• Lentil tissue tests in year four revealed increased Mo levels (>0.3 mg/kg) in treatments where lime was applied.
• Soil samples taken in 2022 showed both the high and low uniformity treatments plus lime have increased soil pH compared to the control. The high uniformity has had the greatest impact on soil pH across the 5 to 30 cm sampling depths. 

• Removing subsoil compaction is critical and for some soil types can dramatically improve access to deep soil moisture.
• Correctly ground-truthing the depth of the compaction layer can drive the success or failure of ripping outcomes.
• Yield increases at the Goomalling site were largely driven by very deep ripping, with either the very deep ripper or delver, with yield increases of 0.55-0.74 t/ha, an increase of 74-93%. The only other treatment to increase yield was mouldboard ploughing on its own with a 0.44 t/ha, 55% yield increase.

At three field sites in WA, increased wheat yield was achieved at lower nitrogen (N) application rates when N was balanced with appropriate phosphorous (P), potassium (K) and sulphur (S) applications. Wheat yield was driven by the ratio of N to P and K rather than the absolute concentrations of the nutrients and it is possible to increase profit margins by balancing nutrient inputs.

The level of background nutrients present in the soil at sowing was a key factor in determining the responsiveness of yield to fertiliser applications and how profitable the fertiliser treatments were. Pre-season soil testing to determine the level of residual nutrients will allow growers to balance their nutrient inputs and help to maximise profits.

• Agntain was found to provide little benefit for increasing canola yield. Agritain may have a role in reducing urea toxicity to germinating seeds, when crop seeds are sown close to pre-applied urea (especially when large amounts of N are used).
• This warrants further investigation.

• Agntain was found to provide little benefit for increasing canola yield. Agritain may have a role in reducing urea toxicity to germinating seeds, when crop seeds are sown close to pre-applied urea (especially when large amounts of N are used).
• This warrants further investigation.

With a soil nitrogen content of 153kg N/ha at sowing, Derrimut wheat yielded just less than 6 t/ha with no N fertiliser.

Applied nitrogen (N) significantly reduced the yield of Derrimut wheat following lentils, yield being reduced from 3.2t/ha to 2.6t/ha as applied nitrogen was increased from 0 to 100kg N/ha in 25kg N/ha increments (linear relationship).

• The optimum nitrogen rate, regardless of timing, to maximise yield was 75kg N/ha, though protein contnet was maximised at higher N rates.
• Further investigation is required to define correlations between crop reflectance (NDVI) and N uptake.

• The effect of application of gibberellic acid (ProGibb) on dry matter production and subsequent grain yield of dual purpose wheat was investigated. There were large and significant increases in DM production when Pro‐Gibb was applied.
• A high rate (40g/ha) resulted in a more rapid increase in DM but by the 4th week all ProGibb treatments had produced significantly higher DM than the nil treatment.
• Average dry matter increases were around 30%, i.e. from 1.26tDM/ha to an average of 1.64t/ha.
• In contrast seven weeks after application the nil treatment produced significantly more DM than the ProGibb treatments i.e. ProGibb treated plants appeared to suffer a payback from the extra growth. Importantly this effect was not carried through to grain harvest with no significant differences between treatments being measured.

• Rhizobia symbiotially fix close to three million tons of nitrogen a year worth $4 billion.
• The Australian Inoculants Research Group (AIRG) and its predecessors have controlled and maintained the quality of legume inoculants through collaboration with industry, universities and R&D bodies for close to 60 years. 
• A symbol of inoculant quality assessment by an independent laboratory is the dispaly of the green tick logo. 
• These are different innoculant groups specific for different legumes.
• Correct storage is important to maintain high numbers of rhizobia in the inoculants. 
• The AIRG continue to monitor the quality of legume inoculants at different points in the supply chain and works closely with teh manufactures to ensure that Australia's growers have ongoing access to efficacious products. 

• ‘Compass type’ varieties with good early vigour, combined with a prostrate growth habit are the best competitors (Compass, Fathom, Scope CL, RGT Planet).
• ‘Hindmarsh type’ and ‘Urambie type’ varieties with very slow early vigour are poor competitors (Hindmarsh, Spartacus CL, Urambie).
• In the presence of grass weeds there was an average of 0.9t/ha yield loss across all barley varieties.
• Three years of data has reinforced that certain varieties can be used as a non-herbicide option for grass weed control.

• Trifluralin was very effective, reducing ryegrass numbers by 60 percent.
• The use of oilseeds and pulse crops provided the opportunity to effectively control resistant ryegrass using different chemistries (even within Group A - dims).
• Cutting hay is a profitable option with low risk and importantly very effective in reducing ryegrass if managed correctly.

• Crop sensors are a useful tool for measuring and mapping the growth of crops, however their limitations need to be recognised.
• Poorer crop growth and lower sensor NDVI values can indicate lower N availability within a paddock, but this should be ground truthed, rather than assumed as there are many potential constraints to crop growth that could also be the cause.
• The use of an N-rich strip in conjunction with crop sensors can provide an indication of the likely grain yield response to N.
• The N rate calculation still requires a yield prediction – a potential fit with APSIM / Yield Prophet.
• Utilising predefined paddock zones created from historical yield and/or soil data may help to refine the use of crop sensors for variable rate applications.

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.

• Slugs are a major pest for emerging canola crops in the high rainfall zone (HRZ)
• Detection across large areas is difficult from the ground
• Remote plant counts can be produced using images collected by drones
• Information can be returned to the grower within five days
• Only two out of every five days had suitable flying conditions, causing image collection to be delayed

• Liquid P applications must be considered a viable option in these farming areas considering these results. It should also be pointed out that this is only one set of trial data in one year for this area. These results indicate that more trial work on LMAP needs to be conducted in the future. 
• Based on previous trials from other areas, the above results indicate that soils in these areas are able to tie up P and that the use of the liquid form of P as LMAP is a viable option for broadacre cropping where this occurs. 
• Finally this trial indicates that a positive yield response can be gained from additional use of N fertilisers, as seen in treatment 5, which was a combination of urea and MAP granules. 

In a trial on Yitpi at Corack there was not yield or margin benefit from using flutriafol on fertiliser at either 400 or 800mL/ha rate, despite low level stem rust and yellow leaf spot infection in the top three leaves of the crop.

• High rates of seed and fertiliser could indeed be a useful tool for controlling weeds. Seed costs would be a little greater but the ability to control the weeds without using chemical - particularly in a situation where resistant weeds become a problem, could certainly make the cost acceptable.

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.

• This site was unresponsive to N and there was no significant effect of either seed rate or N timing upon yield.
• Crop vigour was poor through the season and this was most likely related to subsoil acidity and aluminium toxicity.
• Plant testing confirmed adequate supply of nutrients.
•  

• There is an opportunity to use locally available amendments in place of inorganic fertiliser.
• High rates of surface-applied chicken litter tend to have a better yield response than either surface-applied compost or inorganic N fertiliser.
• Stability of these organic products may provide a less risky option for managing inputs with no need for top dressed urea in the first two years.

A yield increase is apparent in figures 2 (circled) and 3 (see attached Trial report) at the ripped only treatment in the eastern plot, however this is not seen in the western plots and does not stand out in graph 1. Results presented in Graph 1 generally show only slight differences with the greatest response observed in the gypsum only treatment on the eastern plots. This soil was highly sodic at 10cm and as could be expected the gypsum would make a quicker impact on sodicity, thus allowing for improved drainage that may have improved crop production. Gypsum would take longer to impact on subsoil sodicity and may show a response after several years of data are collected

Yield stability and Adopting VRT.
In the initial phase of the project, trial paddocks were selected that had a high degree of
variability. The aim was to exploit this variability to increase whole paddock profitability.
As we learnt more about crop performance in individual paddocks, it became apparent
that some paddocks had a high degree of variability from season to season as well as
between zones (i.e. a high performing zone one season could be a low performing zone
the next). This makes using variable rate technology (VRT) to achieve target yields is
very difficult.
We have developed some rules of thumb for determining if VRT is likely to be profitable
based on the percentage of the paddock that is stable through time.
Highly suited to VRT = >70% Stable
May suite VRT = 55-70% Stable
Unlikely to suit VRT = <55% Stable
Our research shows that unstable zones within a paddock are usually impeded by soil
physical or chemical constraints such as water logging, sub soil acidity, sub soil
compaction. Water logged sites tend to be low yielding in wet seasons and high yielding
in dry years. Sites with subsoil problems tend to perform like medium zones in seasons
with a soft finish and like low zones when there is a dry end to the season.
Trial results have given economic responses (up to 500kg/ha) in the first season to deep
ripping to overcome a tight subsoil.
Most trial sites have not given economic yield responses to additional applications of
nitrogen, phosphate (and potassium on some sites). To date the most profitable treatment
has been the low fertiliser input strategy in high or low yielding seasons.
7
Water Storage Determines Yield
University of Western Australia honors student Josh Whitwell joined the project to assess
how water holding capacity of soil affects yield in that zone. Josh found that grain yield
was determined mainly by a soil’s ability to store and supply water to plants. The high
productive zones commonly had soil profiles that could store larger amounts of water and
supply it back to the crop. Of the 45 sites investigated, 40 were found to have limited
rooting depth due to critical amounts of pH, EC and soil strength. This suggests there is
scope to increase grain yield by ameliorating subsoils.
Focus for 2006 and 2007
With the project extension now approved we intend to focus on continuing research on
the main trial sites to increase replication through time. We hope with the additional two
trial years we can better understand how seasonal conditions interact with zone
management.
We also intend to compare the different paddock zoning methods used by our
collaborating partners, Gamma radiometrics, (B Whelan, Sydney University) and Crop
biomass image analysis (I Mailing, Silver Fox) with zoning from actual yield data.
Economic Analysis
Over the three trial years we have seen a large fluctuation in fertiliser cost and grain
prices.
For all economic calculations the prices have been standardized to eliminate year to year
fluctuations in grain price or fertiliser cost. This has enabled comparisons through time.
• Wheat price – A net in bank wheat price of $180/t plus or minus AWB golden
rewards quality bonification (July 2005). The $180 net in bank price reflects the 5
year average for wheat delivered Corrigin.
• Malt and Feed Barley price – A net in bank wheat price of $198/t (malt) and $153/t
(feed) plus or minus quality bonification. The net in bank price reflects the 5 year
average for barley delivered Corrigin.
• Lupin price - $190 net in Bank.
• Canola price - $355/t net in Bank plus and minus oil bonification as per grain pool
July 2005. This reflects the 5 year average net in bank canola price for Corrigin.
• Fertiliser prices – 2004 Company list prices were used for all 3 trial years.

VRT Performance

Matching fertiliser inputs to productivity zones (VRT) was rarely the most profitable strategy. Table 1 summarises the 9 successful trials undertaken in 2006 and 2007. These were above 5 average production years for the Corrigin area. It is assumed that the low, medium or high fertiliser treatments were blanketed across the whole paddock. The VRT treatment involved apply low inputs to the poor productivity zone, medium inputs to the average productivity zone and high inputs to the good productivity zone. This summary shows that in 8 of the 9 trials a blanket application of low or medium fertiliser rates was the most profitable way to fertilise the paddocks. High inputs were never the most profitable approach. The VRT approach was only most profitable in 1 of the 9 trials. The high input treatment was the least profitable strategy in 6 of the 9 trials.

Phosphate responses

Many of the paddocks where we had our trials were un responsive to phosphate. Our research has shown that many soils now have sufficient levels of phosphate that crops either don’t respond to additional applied phosphate or the responses are very small. The WA wheat belt has been in a phosphate building phase since clearing. Many farms now have sufficient phosphate levels. Fertiliser regimes could now be reduced to a maintenance regime. This would offer significant savings to growers especially given that the price of phosphate has tripled in the past two years. There would also be some significant environmental benefits to preventing over fertilising.

Best Fit for VRT

We feel that in the Corrigin area the most economic use of VRT will be for patching out potassium on responsive soil types as well as ameliorating soil with applications of lime or gypsum in the areas which have the highest requirement, rather than blanket applications on areas that do not require amelioration. VRT could also be used for tactical applications of nitrogen. Where the paddock is blanketed with N and P for and average production season. In an above average season additional nitrogen should be applied to the high productivity zones where the demand for additional nitrogen is likely to be highest.

Precision farming tools such as EM surveys and yeild mapping can add greatly to our understanding of grain yield and quality variation across a paddock. The results of N fertiliser and sowing rates on Silverstar wheat demonstrated that:

• grain yield differences are determined by soil type.
• high sowing rates can contribute to lower screenings but does now guarantee lower screenings.

The larger scale trial work raised issues on how to interpret small scale plot work. There is a greater need for researchers and farmers to work together towards identifying and interpreting paddock variability, before large scale, and often costly, management practices are put in place. 

• Remote sensing can confidently be used to map a rice crop’s panicle initiation (PI) nitrogen (N) uptake.
• A remotely sensed image of nitrogen uptake at PI can identify variability in the uptake and enable variable rate nitrogen topdressing to maximise grain yield with reduced risk.
• Remotely sensed data has been collected using field spectroradiometer (SVC HR1024), multispectral cameras including the MicaSense RedEdge, Tetracam MCA and Headwall Hyperspectral Imager, and Worldview 3 satellite data.

• Blackleg internal infection was found to be greater in retained seed compared to the original hybrid.
• Some trials showed a yield loss when retained sowing seed was used.
• The use of farmer retained hybrid seed must be questioned based on these and other trial results.

• The wetting agent /humectant SE14 was applied at seeding to see if crop establishment was improved in a dry sown oat crop near Lake Grace on a soil without non-wetting issues
• Significantly more oat plants germinated at SE14 3L/ha + water 47L/ha compared to the nil
• There was no significant difference in plant establishment between two different water rates used for applying the wetting agent
• It is unknown whether the increased plant establishment resulted in increased yield, as yield was not recorded.

•  Yields were significantly higher under narrow row spacing, but sowing direction had no influence on yield.
• Weeds had a significant effect on yield, but the scale of yield penalty (t/ha yield loss) did  not alter with row spacing or sowing direction in 2015.
• Weeds established faster where row spacings were wider, however by late tillering, all treatments had similar weed numbers and biomass levels.

• Yields were significantly higher under narrow row spacing, but sowing direction had no influence on yield.
• Weeds had a significant effect on yield, but the scale of yield penalty (t/ha yield loss) did not alter with row spacing or sowing direction in 2015.
• Weeds established faster where row spacings were wider, however by late tillering, all treatments had similar weed numbers and biomass levels.

• Condition score stock every time they come into the yards and use the “Lifetime Ewe” app to guide costeffective decisions on feeding regimes.
• Ewes pregnancy-scanned for twins and singles and managed as separate mobs, enables tighter feed management of the singles without compromising the overall lambing percentage.
• Use all the tools - Pastures from Space, condition scoring Lifetime Ewe app and stocking rate calculators - to ensure mobs are not being over or under-fed (both options can lead to costly mistakes).

When using the BlacklegCM App the information contained within the predictions is an indication of potential, not a guarantee for profit. The results from the York trial, where it was more of a case of minimising the loss received rather than focusing on making a profit, showed that regardless of the predications made by the app there was always going to be a loss received at this site due to poor seasonal conditions. The BlacklegCM App is an ideal fit to provide an indication of risk to a canola crop from blackleg, and the potential economic impact of this decision (positive or negative), as the user inputs the parameters that they are assessing prior to undertaking the decision to execute this plan.

While the analysis of using the BlacklegCM app as a predictive tool could not be completed for the 2020 trial results, the data collected from this season’s trial was able to show that the new technology that has been developed to further enhance the growers ability to minimize the impact of blackleg infection is effective. The results also showed that Pioneer 44Y27 (RMR) yielded higher when compared to the BASF 3000 (MSS) used in the same trial sequence which correlated with the Stingray (MR) having a greater yield across both trial sites than the Bonito (MS) under blackleg pressure, supporting the benefits of robust blackleg resistance ratings from broader trials.

Extension of the app needs to be clear that the figures that the app develops are based on the background research, the parameters put into the app and that there is still a range of variability to allow for within the system.

• Compaction is a subsoil constraint in North Hyden sandy soils.
• The first year of results indicate that deep ripping can be profitable in these soil types in North Hyden.
• The site variation and the design of the demonstration highlighted the response is not guaranteed; more investigation is required to identify why certain parts of the demonstration were more responsive than others to deep ripping and how to map and identify soils responsive to deep ripping.

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 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. Fertiliser rates were selected after discussing with farmer that the lower yielding zones would never produce yields comparable to medium and high yielding zones, due to the low fertility and poor water and nutrient holding capacity of the soil. The farmer believed that that fertiliser was being wasted on the sand zones of his farm, and wanted to see if cutting fertiliser rates would be detrimental to yield in this zone.

NDVI satellite imagery was collected to establish dry matter production difference in 2011. The crop was sown as brown manure peas and therefore there were no yield results. Yield data will be collected in 2012 as part of the trial program.

• Without this intensive mapping the paddock would have been either under or over limed and fertilised resulting in either a loss of productivity or a waste of fertiliser/lime dollars and possibly both.
• Whilst it’s economically beneficial to apply variable rate technology for a liming program, until more cost efficient soil testing methods are developed, the economic justification may not be there for soil nutrients.

In 2010, at Wass brothers’ property in Nyngan, a very wet season caused the normally poor performing areas to perform just as well as the good areas in this paddock regardless of additional nitrogen application. In other paddocks across the farm, there were significant yield differences across each paddock. However, in the previous years Wass’s have always wanted to apply N and have had mixed results possibly because of soil and water variability. Most seasons they have areas that burnout and areas which could use a higher application of N and give a better yield. In 2011, Hayden intended to try to understand what was driving these differences, and yield maps are a way of spatially determining different zones. Therefore, this trial was set up.

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.

Because there was no effect of fertiliser on the yield it meant any potential benefit from VR was greatly reduced. This can likely be put down to the high levels of soil N recorded at the start of 2011. The trial does suggest that this paddock was over fertilised as there was no significant loss of yield from a 40kg/ha reduction in urea in either trial.

There was no response shown to varying nitrogen rates across the 4 yield zones on this paddock. This could be due to the adequate levels of nitrogen present before seeding as show in the 0-10 and 10-60cm soil test results and also reinforced with the NDVI esults, this would stem from good fertiliser history and rotation from the Harkness’s.This could give confidence that rates could be reduced on the lower yielding areas without risk of impacting on yield and consequently increasing gross margins across the paddock by saving wasted inputs on poorer performing soil types and leaving rates higher on better performing areas to maximise returns when seasons are more favourable.

The NDVI map has a strong correlation to the final yield, which indicates that the variable rate nitrogen did not achieve the goal of levelling out crop yield. This may be due to the dry finish to the season. This result does however confirm the concept of using in-season satellite imagery (typically late July, early August) o manage final yield through a variable rate intervention.

• In 2011 optimised variable rate N applications increased gross margins by $11- $22/ha in two barley crops.
• In 2012 variable rate N applications increased gross margins by $13-$20/ha in three wheat crops, based on yield response and fertiliser savings.
• Increases in grain protein of 0.3 – 0.5% have been observed.

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.

With good soil phosphorus reserves ‘P replacement’ is a safe and viable option that will help farmers manage their inputs and maintain soil fertility in high yielding areas of the paddock.

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 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.

This year there was no big benefit from variable rate fertilizer in relation to yield. This is not unexpected given the dry season.

This trial gives some confidence that cutting fertilizer in particular P back on the low zone did not impact yield and had the best gross margin, therefore is a good strategy to reduce costs on the lower performing parts of the paddocks. This is consistent with current DAFWA and GRDC research findings that less phosphorus can be applied on soils with good P history without penalizing yield. Similarly it demonstrated the potential to reduce rates on the higher production zones depending on the season as tissue tests indicated adequate nitrogen just prior to the late N application. It is likely there was also more nitrogen available as a result of ripping increasing nitrogen mineralization and plant root access to water and nutrients. Reducing N applied after ripping is a recommended strategy to reduce the risk of the producing high biomass and the crop haying off early with a dry finish.

The estimated yield potential of the zones was not reached with the high zone about 1.5 t/ha below potential. This is consistent with farm observations that found there was a penalty of about 1 t/ha for crops sown later than 7 days from the 22nd May crops in this dry season.

High resolution six meter imagery was found to be very useful to identify management issues and map non-wetting soils, particularly the early July image which highlighted emergence issues. The non-wetting areas can be mapped and treated by ploughing those areas paddock not the whole reducing the cost of treatment. Ground-truthing showed the 6m resolution was high enough to identify problems with the bar such as running out of fertilizer. These are management issues that can be adjusted to improve efficiency and production to improve yield. 

In the case study paddock the imagery has highlighted issues that were not evident from the yield maps such as residual compaction from old corners and where the ripper and spader lifted over a water pipe (the red line in the top north east corner). This paddock has been deep ripped twice but old compaction is still visible suggesting it is beyond the current ripping depth of 400mm. The late season imagery was too late to see any big differences in biomass. An optimal time to capture imagery appears to be mid-July.

Applying low fertilizer to the low production zone is both a good economic strategy to improve profitability and prevents over fertilizing that increases the risk of nutrient leaching in these pale sands that have limited capacity to store nutrients.

Additional N did not have an economic advantage in this season. Paddock and demonstration site suffered from the dry 6 weeks period mid season. Stem rust devastated potential 3 ton crop reducing yield by 50%. This combination resulted in poor yields, low test weight and high screenings. Good soil showed improved protein over deeper sand regardless of extra N applied. Extra N marginally improved protein but not enough economically to apply more.

• Additional N did not have an economic advantage in this season.
• Paddock and demonstration site suffered from the dry 6 weeks period mid season.
• Stem rust devastated potential 3 ton crop reducing yield by 50%. This combination resulted in poor yields, low test weight and high screenings.
• Good soil showed improved protein over deeper sand regardless of extra N applied.
• Extra N marginally improved protein but not enough economically to apply more.

KEY FINDINGS:

• Cereal variety choice can have a large impact on Pratylenchus thornei (Pt) population build-up within paddocks, which can then affect how following crops and/or varieties perform in the rotation.
• Significant differences were evident between varieties with an 8.9-fold difference in final Pt populations between the best (Commander) and worst (Mitch) entries.
• Very susceptible varieties should be avoided in paddocks with known root lesion nematode (RLN) populations as they can increase the population to high risk levels in one season (e.g. 19.1-fold increase with Mitch).
• There was no significant difference between varieties in crown rot inoculum level that developed during the season based on postharvest PreDicta B assessment.

Conclusions

Cereal variety choice can have a significant impact on the build-up of Pt populations within paddocks with an 8.9  fold difference in final populations between the best and worst variety at this site in 2015. Starting Pt populations of below 2.0 Pt/ g soil are considered low risk, populations between 2.0 and 15.0 Pt/g soil are considered medium risk and above 15.0 Pt/g soil are considered high risk for yield loss in intolerant crops or varieties in the northern region. This could have serious consequences for the production of following Pt intolerant crops and/or varieties within the rotation with all but two entries (Commander and Suntop) increasing the Pt population from a medium to a high risk level in one season or with one variety (Mitch) increasing the Pt population as high as 105.0 Pt/g soil at this site in 2015. Recent NSW DPI research has also demonstrated that significant yield loss still occurred in the moderately tolerant wheat variety EGA Gregory with high risk (>15.0 Pt/g)  populations in the top 30 cm of soil at sowing. Very susceptible varieties should be avoided in paddocks with known RLN populations as they can blowout the population to high risk levels in one season.

Although varieties appear to significantly differ in their yield in the presence of crown rot infection, differences in the levels of partial resistance, which limits the rate of spread of the crown rot fungus through the plant during the season, do not appear to result in significant variation in inoculum levels at harvest. Partial resistance does not actually prevent the plant from being infected but rather slows the rate of fungal growth in the plant arguably delaying expression of the disease which can translate into a yield and grain quality (reduced screenings) benefit. However, the crown rot fungus, while being a pathogen when the winter cereal plant is alive, is also an effective saprophyte once the plant matures and dies. This saprophytic colonisation of infected tillers late in the season as the crop matures is the likely reason why limited practical differences in residual inoculum levels are created between varieties and winter cereal crop types.

 

Further research across sites is required to confirm differences in resistance of barley and wheat varieties to Pt as this can have significant implications for the build-up of Pt populations within a paddock and hence following rotational choices. For instance, while it appears that Mitch has a useful level of tolerance to crown rot (average 0.54 t/ha higher yielding than EGA Gregory in 2015), its increased susceptibility to Pt resulted in it taking nematode populations from a medium risk level at sowing to an extremely high risk level by harvest at Macalister in 2015 (Figure 1). Hence, Mitch should only be considered for production in paddocks known to be free of Pt as its increased susceptibility to Pt is likely to override the yield gain in the presence of crown rot when considering the whole rotational sequence.

 

• Cereal variety choice can have a large impact on the build-up of Pratylenchus thornei (Pt) populations within paddocks which can then impact on the performance of following crops and/or varieties in the rotation.
• Significant differences were evident between varieties with a 22-fold difference in final Pt populations between the best (SuntopA) and worst (MitchA) variety.
• Very susceptible varieties should be avoided in paddocks with known Root Lesion Nematode (RLN) populations as they can increase the population to high risk levels in one season.
• There was no significant difference between varieties in the level of crown rot inoculum they developed during the season based on post-harvest PreDicta B assessment.

• Seasonal conditions had an overriding influence on crop performance and bean yields in 2015. 
• Early sowing benefited yields in less favourable low/medium rainfall environments where biomass production was lower.
• Sowing densities above the recommended rates of 24 plants/m2 led to high increases in biomass production at flowering time however, had no effect on final grain yield.
• Seed size was small in 2015, adjust seeding rates accordingly to maintain optimum plant populations for 2016.

A summary of results is presented in the associated report.

Very little yield data is available for many of the crop species from the 2006 season. Furthermore, for some crop species, notably chickpeas, seed production was severely disrupted by the drought and the release of some of the newer varieties has been delayed by a year.

• Zymoseptoria tritici and Pyrenophra tritici-repentis, the disease-causing pathogens of septoria tritici blotch (STB) and yellow leaf spot (YLS), can produce ascospores on wheat stubble regardless of their resistance status.
• Any infected wheat stubble has the ability to initiate an epidemic for up to 2 years.
• Reduce harvest cut height to limit Z. tritici colonising stubble.
• Excess harvest material must be removed from the paddock to produce a net reduction of Z. tritici inoculum.
• Minimise disease impacts by using an integrated approach to management.