• 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.

• Analysis of wheat crops sown after rice harvest in the Murray Irrigation Ltd districts (MIL) found that increasing yields required different management depending on soil type and irrigation layout.
• Four management factors that limit winter crop yields were identified: waterlogging, late season water stress, under-fertilisation and low soil pH.
• In the MIL districts alone, increasing wheat yields after rice from the current median to the 80th percentile would result in an additional 20,000–30,000 tonnes per annum ($4–6 million at $200/t).
• If all rice areas were sown to wheat after harvest every year and 80th percentile yields achieved, an additional 128,000–138,000 tonnes of wheat would be produced ($26–$28 million at $200/t).

• This trial is a large-scale experiment, the data collected provides an indication of treatment effects and demonstrates benefits and pitfalls of adopting these subsoil acidity management methods on a large-scale. The small plot trials are more accurate and provided detailed statistical analysis of the impact of different treatments.
• Further years of research and analysis from this site and other sites will confirm these findings.

• High-pressure injection shows promise as an alternative method for applying fertiliser into the soil.
• Deep banding fluid fertilisers with extra long knife points is another option which also showed promise.
• This research is still in its early days.

Field peas can respond to the use of rhizobia innoculants.

Response to inoculant was positive at this site over the untreated, however, there was no differences between inoculant types

Chickpeas need to be inoculated in paddocks which have not had chickpeas before.

The season was too dry to see the benefits of inoculating legume seed with rhizobia.

For key messages please see the attached trial report.

• Annual medic had lower levels of soil N (kg/ha) remaining in the soil post-harvest compared to balansa clover and subterranean clover at Sherwood.
• Annual ryegrass establishment was greater in crops following wheat, compared to crops following a pasture break crop.
• Overall pasture biomass production was greater at Bordertown compared to Sherwood.
• Wheat yields at Sherwood were greater following balansa clover and subterranean clover, compared to following canola and cereals options, wheat, barley and oats.
• Grain barleys Compass and Rosalind have demonstrated a capacity to produce biomass as a forage or hay option; feed tests need to be considered to ensure they are as favourable as forage options for livestock production. 

• Research funded by the GRDC- SARDI Bilateral Research Agreement.
• Focus on ‘Integrated Farming Systems in the Medium Rainfall Zone’.
• Three field components, long-term rotational trials, targeted agronomic trials and focus paddocks.

• Sow chickpea crops between standing wheat rows.
• Sow the following wheat crop directly over the row of the chickpea crop from the previous year.
• Keep wheat stubble intact and do not spread it across the soil surface.
• This will maximise yield of both chickpea and wheat crops and reduce the incidence of crown rot in the wheat phase of the rotation sequence.
   

• Insect prest pressure was generally low in Victoria and Southern NSW for 2001.
• There was no significant yield differences between the different pest control treatments, with the site mean being 4.92t/ha.
• Selective insecticides promote and encourage beneficial species which can be useful in combating harmful pest species attacking crops.

Insecticide sprays are effective in controlling crop pests, but do not always provide yield benefits.

These trials demonstrate that certain crop species and cultivars such as barley, oats and grazing wheat, can
suppress weeds effectively at standard establishment rates. This may be due to their ability to compete
effectively with weeds for valuable resources, or their potential to exhibit allelopathic effects associated either
with the crop or remaining residues following harvest.

• The seed catcher treatment reduced the ryegrass seed bank from 2007 most effectively
• Delaying sowing in 2008 from the 29th May until the 6th June decreased the ryegrass population by 55%.

• A combination of chemical and non-chemical weed control strategies can extend the life of herbicides and improve the sustainability of intensive cropping systems.
• Windrow burning, crop topping and chaff carts are options which can reduce the ryegrass seed bank without any yield penalty.
• Cutting a cereal crop for hay for one year can significantly decrease ryegrass levels in the following crop.

• An integrated weed management (IWM) approach was used incorporating integrated Harrington Seed Destructor (iHSD), herbicide, hand picking, crop rotation and early grazing opportunities
• After seven years wild radish numbers were controlled on paddocks that previously had high densities 
• Between 2018 and 2020 the radish population was reduced by 71%

• Integrated weed management is the best approach for long-term control of herbicide resistant annual ryegrass.
• The most effective cultural control method trialled was mouldboard ploughing which was significantly better than stubble.burning or direct sowing into retained stubble in terms of in crop weed numbers.
• Sakura + Avadex Xtra IBS herbicide regime achieved the best control of annual ryegrass later into the season.
• Crop establishment, wheat yield and grain quality were not affected by the choice of weed control method in this trial.

• Pre-emergent weed control with Sakura reduced annual ryegrass populations by 85-97% compared to the control

• Combining Sakura pre-em with Boxer Gold at GS11 resulted in 97% weed control 180 days after sowing

• Sakura provides robust pre-em weed grass control and can be used as one element of an integrated weed management approach

• Other practices that can form part of an IWM strategy include paddock selection, cultural control, grazing, land fallowing and chemical rotation

• Continuous cropping and a reliance on pre-sowing weed control measures is not an effective way to manage herbicide resistant annual ryegrass over the long term.
• The increase in weed numbers over time can be limited by adopting an intensive and high cost herbicide strategy, but this will not deplete the seed bank.
• Increasing annual ryegrass density was associated with decreased grain yield.

• The use of Lucerne in the Upper Wimmera catchment and similar areas can be extended away from traditional areas such as river and creek flats.
• Introduction of lucerne into grazing systems lengthens the period of available green feed and can allow for enterprise change such as adding a lamb finishing operation to the farm business.
• Sowing time of lucerne is best suited to late winter.
• Soil testing is important to test for nutrient deficiencies and pH prior to lucerne establishment. Adequate lime and fertiliser should be applied to address deficiencies prior to establishment. Attention must be paid to ensuring that aluminium levels are suitable for lucerne production prior to sowing.
• A sub soil pH test should be taken to ensure that there are no acidity or aluminium toxicity issues at depth which could affect the lucerne plants as their roots penetrate the sub soil.
• Weed control is of critical importance before and during the establishment phase of lucerne pastures.
• Sowing depth of lucerne is important to allow an even germination. Care should be taken not to sow seed too deeply. The seed should be covered by 1 – 2 cm of soil, ensuring good soil contact.
• Control of annual grass and broadleaf weeds is of critical importance during the life of the lucerne stand if maximum production is to be achieved.
• A suitable fertiliser regime including the use of potash needs to be applied to replace nutrients removed by the lucerne system.
• Lucerne pastures can produce high quality hay which can enhance the farm’s production system if kept on farm.

Herbicide strategy 1 (HS1), which was based on atrazine pre-sowing followed by clethodim (Select) post-emergence reduced ryegrass plant density relative to the untreated control by 57%. However, use of propyzamide pre-sowing, followed by atrazine and Select + Factor (HS 2) increased ryegrass control to 77%. Canola variety had a significant effect on ryegrass spike density (P=0.002). When averaged across the sowing dates and herbicide strategies, ryegrass growing in HyTTec Trophy produced 52 spikes/m2 as compared to 78 spikes/m2 in Bonito (33% reduction). HyTTec Trophy is a new hybrid triazine tolerant variety from Nuseed, which is known for high early vigour. Herbicide strategies also had a significant effect on ryegrass spike density (P<0.001). Ryegrass grown without any selective herbicide treatment (control – HS3) produced 128 spikes/m2 as compared to 40 spikes/m2 in HS1 and 29 spikes/m2 in HS2. This works out to 69% reduction in HS1 relative to the control and 78% reduction in HS2. Herbicide strategies had the largest effect on canola yield (P<0.001). HS1 and 2 produced canola yield of around 0.8 t/ha, which was almost 50% greater than the yield obtained in the control.

Inter row sowing in no-till systems works well and can increase crop profits for wheat, lentils and canola.

Inter row sowing in no-till systems works well and can increase crop profits for wheat, lentils and canola.

Inter row sowing in no-till systems works well and can increase crop profits for wheat, lentils and canola.

Inter row sowing in no-till systems works well and can increase crop profits for wheat, lentils and canola.

• Positive yield responses from the control of yellow leaf spot (YLS) were recorded despite disease levels not exceeding 10% on the top three leaves in this wheat-on-wheat rotation position.
• For the second year in succession there was a significant yield increase (0.12t/ha mean of two fungicide products) from two fungicide applications made at the late tillering stage and the second node stage (GS25 and GS32).
• The yield response from two fungicides corresponded to significantly better disease control than the untreated control and increased the crop canopy greeness.
• Although single fungicide timings produced little or no evidence of YLS control, significant yield increases were measure (0.13-0.14t/ha).
• Nitrogen timing (application of 40kg N/ha at either tillering (GS22) or first node stage (GS31)) had no significant effects on disease levels, yield or quality.

• The level of yellow leaf spot (YLS) control achieved with fungicides applied at tillering (GS22) and third node stage (GS31) in wheat-on-wheat was poor (less than 50% in most assessments).
• Fungicide applied at the third node stage (GS33) was more effective at preventing YLS infection on the top three leaves of the crop than when applied at tillering (GS22).
• Fungicide applied at the third node stage (GS33) generated a significant (0.44t/ha) yield increase over the untreated crop, whereas the equivalent fungicide applied at tillering (GS22) gave no yield benefit.
• Applying fungicide at both tillering (GS22) and third node stage (GS33) offered no advantage over a single application at GS33.
• Nitrogen application at tillering or first node had no effect on yield.
• There was no significant difference in product performance between Tilt and Prosaro.

Plant growth regulators significantly reduced the yield and quality of Gairdner malting barley, irrespective of which fungicide programme was employed.

• Nitrogen applications increased yield, manily through increased tillering.
• Increased plant density reduced yield.
• Spartacus CL and Fathom had the highest yield at optimum nitrogen and plant density.
• Compass and Commander were the least responsive to nitrogen applications.

• In a low-yielding situation at Coreen, Victoria (< 2.5t/ha) following a dry spring, plant growth regulator (PGR) application lead to a significatn yield reduction (0.14t/ha) in early-sown first wheat.
• PGR application significantly reduced crop height in both trials, but did not reduce crop canopy biomass, suggesting that crop biomass was redistrubuted, not recuced.
• The addition of extra nitrogen, over and above farm standard significantly increased grain protein but not yield
• PGR application significantly reduced the normalised difference vegetative index readings taken with Greenseeker, particularly where applicaiton was superimposed on lower amount of applied nitrogen.

• The negative effect of water repellence management at this site is at odds with other work in this project. In both years we have observed a lower grain yield in the banded wetter, mouldboard ploughing and spading treatments than in the control at this site.
• However, the average yield response to mouldboard ploughing and spading was 550 to 600 kg/ha over 28 sites.
• For further details please see the attached trial report.

• Severity of root rot of barley and wheat in farmers fields caused by Rhizoctonia was inversely correlated with crop Zn status.
• Zn was the only nutrient correlated with the severity of Rhizoctonia.
• Zn deficient plants were more susceptible to Rhizoctonia.
• 2.5 kg Zn/ha halved the area suffering from bare patch.

• A factorial pot experiment involving four rates of soil-applied Mn (0, 0.75, 7.5 and 75 mg Mn/pot), four levels of CCN (0, 93, 186 and 372 second stage juveniles per pot) and 12 replicates of one Hordeum vulgare cv. 'Clipper' plant per pot was carried out.
• Four replicates were harvested 28, 73 and 192 days after sowing and each plant was assessed at harvest for growth, Mn content and level of CCN infection • Several plant growth parameters were measured non-destructively during growth.
• Resistance (ability of the pathogen to reproduce on the host) was not influenced by Mn nutrition of the host and equal numbers of nematodes invaded and developed to maturity on all plants despite Mn treatments resulting in plant Mn levels which ranged from severely deficient (0 Mn rate) and deficient (low Mn rate) to adequate (two highest Mn rates).
• However, tolerance (endurance of disease without severe losses in yield or quality) was considerably reduced by the combination of low Mn supply and higher levels of CCN.
• Plant height was reduced by increasing CCN numbers only at the two lowest Mn rates.
• These trends were typical of those observed in all plant growth parameters measured in the final two harvests including dry and fresh weight of roots and tops and total dry weight of grain produced per plant. Maturity was delayed in the severely affected plants.

In a high yielding trial (5-6 t/ha), Baudin barley gave small responses to fungicide (mean 2- 4%), compared to Gairdner which gave no response.

Despite an exceptionally dry growing season (GSR Apr – Nov 235mm) first cereal barley averaged 3.6 t/ha, with Gairdner giving a mean yield of 3.50t/ha and Baudin 3.71t/ha. As a consequence of the season, disease did not develop in this trial (irrespective of variety susceptibility), meaning that it was not possible to examine the interaction between nitrogen timing and fungicide requirement.

The later maturing feed wheat Mackellar was significantly lower yield than the earlier AH category variety Chara, with mean yields of 2.35 and 2.52 t/ha respectively. Much of this difference was due to the poor performance of Mackellar under the seedbed nitrogen application, since when compared at the later nitrogen timing alone, the mean yields were 2.55 and 2.60t/ha for Mackellar and Chara respectively. Fertilising with upfront nitrogen had less detrimental effect on yield with an early maturing variety with lower tillering capacity than it did with later maturing wheat (Mackellar) that had a longer tillering window.

In a decile 1 growing season, with no rainfall in October, barley yielded between 1-1.5 t/ha. Baudin averaged 1.38 t/ha, with the experimental low protein barley VB0229 averaging 1.31 t/ha. Both were superior to Gairdner, which as a result of poorer establishment, averaged only 1.02 t/ha.

Dry sowing resulted in the poorest weed control at seeding and as a consequence this treatment was the weediest later in the year.

• Spray-seed drift during shielded spraying damaged the lupin plants in this trial.
• Lupins yielded well when sown in rows 50cm apart.

• Zinc deficiency occurs on many heavy textured soils in the cereal areas of Queensland.
• Zinc deficiency is greater after long fallows and much reduced in double crop systems .
• In linseed zinc deficiency has been associated with potassium, manganese and occasionally phosphorus deficiency. But in wheat only zinc deficiency has been recognised.
• Zinc foliar sprays are thought to be the best solution.
• The positive effect of double cropping is thought to relate to root factors.

Soil biota hold the key to sustainable crop production via impacts on processes like suppression of disease outbreaks and the cycling of essential nutrients.

1. In dryland conditions, planting in February increased yield of dryland mungbeans by 475 kg/ha over December planting.
2. Irrigation treatments increased mungbean yields by a maximum of 298 kg/ha and 653 kg/ha (planted in February and December respectively).
3. Application of water during mid pod-fill increased grain yield in the December planting but not the February planting.

Intercropping lentil and canola resulted in increased grain productivity at Wudinna, 2019. Intercrop combinations did not over-yield at Warnertown, 2019. Intercropping warrant exploring in low rainfall environments and their potential ancillary benefits, such as increasing groundcover on erosionprone soils, nitrogen fixation, and fodder production as a secondary end use benefit.

The success of break crops to increase wheat production in the Eastern Wheatbelt is dependent on firstly addressing any physical and chemical soil constraints to crop production and where the previous land use is a chemical fallow. In this situation, the grain yield of lupin, chickpea, lentil and field pea was 0.97-1.42 t/ha 0.67-1.1 t/ha, 0.3-0.97 t/ha, and 1.2 t/ha respectively in a below average season. The yield of wheat following legume break crops tended to be higher than either canola or wheat planted in the remaining paddock area. The profitability of double break-crop sequences was negative in many of the sequences evaluated in this study compared to a positive profit for continuous wheat. The profitability of double break-crop sequences can be improved by the inclusion of high value legumes as the second break-crop, but further work is required to lower the risk of growing these species of crops.The yield of wheat following legume break crops tended to be higher than either canola or wheat planted in the remaining paddock area. The profitability of double break-crop sequences was negative in many of the sequences evaluated in this study compared to a positive profit for continuous wheat. The profitability of double break-crop sequences can be improved by the inclusion of high value legumes as the second break-crop, but further work is required to lower the risk of growing these species of crops.

• The results presented in this report are from the first year of a three-year study that investigates the effect of break-crop sequences on wheat grain yield. The site was selected due to its high background levels of ryegrass control, and crop rotation treatments have been designed around weed control as the main rotational factor.
• Grain yield was relatively low compared to the growing season rainfall of 253 mm. Grain yield was affected by severe frost that occurred during grain fill.
• This project will continue with the second crop in rotation for the 2017 season, followed by wheat across all plots in 2018 to assess the benefit of a stacked rotation for subsequent wheat grain yield.