This trial was conducted to evaluate the residual control of button grass in fallow. An establishment of button grass was already present at the site with the majority of weeds ~15-25cm in diameter. These weeds were controlled with Roundup 450 @4L/ ha + Liase @1%. Residual treatments were applied on the 19/11/18, 5 days after the Roundup application.
Significant rain events occurred 3 days after residual application (52mm) and 29 days after application (30mm). There was no new emergence of button grass even in the untreated areas. A second maintenance spray of Roundup was applied to control any surviving mature button grass plants ~30 days after the residual herbicide application. Assessment on the 5/2/19 (77 days after application) still showed no new button grass emergence.
Additional rain events occurred in March 2019 (85mm on 16/3/19 and 35mm on 30/3/19) with an assessment of control conducted on the 1/5/19 (163 days after application). The majority of button grass at this assessment were flowered, up to ~30cm in diameter and expected to have emerged following the March rainfall. Dual Gold 2L provided ~99% control of the emergence flush with Flame at 150-200 mL/ha in excess of 90% control. Stomp Xtra and Valor provided useful levels of suppression and controlled ~70-80% of the emergence. Neither Balance 100 g/ha nor Terbyne Xtreme 1.2 kg/ha provided any button grass control and there was no obvious indication of biomass suppression.

This trial was conducted to evaluate the residual control of button grass in fallow. An establishment of button grass was already present at the site with the majority of weeds ~15-25cm in diameter. These weeds were controlled with Roundup 450 @4L/ ha + Liase @1%. Residual treatments were applied on the 19/11/18, 5 days after the Roundup application.
Significant rain events occurred 3 days after residual application (52mm) and 29 days after application (30mm). There was no new emergence of button grass even in the untreated areas. A second maintenance spray of Roundup was applied to control any surviving mature button grass plants ~30 days after the residual herbicide application. Assessment on the 5/2/19 (77 days after application) still showed no new button grass emergence.
Additional rain events occurred in March 2019 (85mm on 16/3/19 and 35mm on 30/3/19) with an assessment of control conducted on the 1/5/19 (163 days after application). The majority of button grass at this assessment were flowered, up to ~30cm in diameter and expected to have emerged following the March rainfall. Dual Gold 2L provided ~99% control of the emergence flush with Flame at 150-200 mL/ha in excess of 90% control. Stomp Xtra and Valor provided useful levels of suppression and controlled ~70-80% of the emergence. Neither Balance 100 g/ha nor Terbyne Xtreme 1.2 kg/ha provided any button grass control and there was no obvious indication of biomass suppression.

This trial was established to evaluate residual control of common sowthistle in fallow. Treatments were applied in late December 2021 to a paddock cropped to cotton in 2020/21 and then conventionally farmed. No stubble cover was present and dead or dying weeds provided ~20-40% ground cover. The trial received ~23 mm of rainfall during the first 4 days after application.
The site was inspected at 40, 58, 75 and 126 days after application (40, 58, 75 and 126 DAA) with no seedling weeds present at the initial or final inspection. Seedling weed counts were conducted at 58 and 75 DAA with glufosinate at 5 L/ha applied at 62 DAA to control weeds present at the 58 DAA count. In the fortnight following the clean-up spray, ~180 mm of rainfall was received. A new seedling weed flush was counted at 75 DAA. Seedling common sowthistle and caustic weed (caustic creeper) were present at each assessment.
Despite ~120 mm of rainfall since residual application, common sowthistle was only at trace levels at the 58 DAA assessment with no significant treatment differences. Untreated common sowthistle populations of ~4 /m2 were present at the 75 DAA assessment. Both rates of Valor alone and the experimental Group 14 R provided complete control with mixtures of Valor with Dual Gold or Impose, Voraxor at both rates and Tordon 75-D reducing common sowthistle counts by >90%. Dual Gold, Balance and Terbyne Xtreme did not provide acceptable levels of common sowthistle control under these conditions.
At the 58 DAA assessment, caustic weed was present in the untreated at ~0.6/m2. All treatments other than Balance and Gp 27 C reduced caustic weed numbers by >90%. By the assessment at 75 DAA, caustic weed density was ~2/m2 with complete control from both rates of Valor alone, Valor + Dual Gold, Group 14 R and both rates of Voraxor. The mixture of Valor with Impose also provided >90% control.
In this situation with ~300 mm of rainfall, all treatments containing Valor (alone or in mixture), Voraxor, Tordon 75-D and an experimental Group 14 herbicide provided excellent levels of residual common sowthistle control (95-100%), up to ~70 days after application. Valor, Voraxor and the experimental Group 14 herbicide also provided excellent levels of residual control of caustic weed. Balance, Dual Gold and Terbyne Xtreme only provided moderate levels of weed suppression under the high rainfall conditions.

This trial was established to evaluate residual common sowthistle control in fallow. Treatments were applied in early January 2022 to a paddock cropped to wheat in 2021. The site had ~10-20 cm tall wheat stubble with ~100% ground cover. The site received a commercial fallow knockdown spray ~2 weeks prior to the residual herbicide application.
The site received ~21 mm at 7 days after application (7 DAA) and a total of ~520 mm over the duration of the trial. Weed counts were conducted at 19 DAA, 55 DAA and 91 DAA. Data from the 19 DAA assessment was ignored as there were a small number of 6-9 leaf common sowthistle. These weeds would have been emerged at the time of residual herbicide application but covered by the dense groundcover. A commercial fallow double knock was applied on 33 and 39 DAA to control weeds that had emerged prior to the residual herbicide application. In the two weeks following the double knock application ~230 mm of rainfall was recorded.
Residual control was assessed at 55 DAA with untreated common sowthistle populations of ~2.1/m2 at the cotyledon to 2 leaf stage. Residual control >90% was achieved from all treatments containing Valor, both rates of Voraxor, Tordon 75-D, Terbyne Xtreme and an experimental Group 14 herbicide despite ~290 mm of rainfall since application. Common sowthistle counts in the Balance, Dual Gold alone, Gesaprim and experimental Group 27 herbicide treatments were not significantly different to those in the untreated.
In the following five weeks, an additional 230 mm of rainfall was received. Assessment at 91 DAA found common sowthistle at three distinct growth stages. The largest were at stem elongation and expected to be primarily the seedlings assessed at 55 DAA. Similar treatment patterns were observed to the 55 DAA assessment.
Rosette staged common sowthistle at ~15-20 cm diameter were present at ~3.3/m2 in the untreated. These weeds are likely to have emerged from rain events between 50-59 DAA when a total of ~95 mm of rainfall was recorded. The most effective control (~80-90%) was obtained from all treatments containing Valor or the experimental Group 14 herbicide.
Seedling staged common sowthistle at 2-3 leaf were present at ~0.6/m2 in the untreated. These weeds are likely to have emerged from rain events between 75-82 DAA when a total of ~187 mm of rainfall was recorded. No treatment provided significant control, however the lowest weed counts were present where Valor or the experimental Group 14 herbicide were applied.
In this situation all treatments containing Valor (alone or in mixture), Voraxor, Tordon 75-D, Terbyne Xtreme and an experimental Group 14 herbicide all provided good levels of residual common sowthistle control (90-100%), up to ~55 days after application with ~290 mm of rainfall. Valor, and the experimental Group 14 herbicide provided longer residual control under the high rainfall conditions but did not effectively control an emergence that occurred ~80 days after application following >330 mm of rainfall. Balance and Dual Gold provided poor levels of weed suppression under the high rainfall conditions.

This trial was conducted as part of a series to evaluate the potential of a range of fallow registered residual herbicides and potential new options for management of common sowthistle. Management of common sowthistle in fallow is a major industry challenge with increasing levels of glyphosate resistance or tolerance. Although common sowthistle populations are typically scattered and at low densities, management alternatives including residual control are keenly sought.

This project was designed to evaluate the residual efficacy of three Group 14 herbicides (Reflex, Terrad'or and Terrain) when applied as standalone options, or in combination with Balance or Terbyne Xtreme. The trial was conducted in a paddock that was double cropped after sorghum production in 2021/22. The sorghum stubble was ~28 cm tall with ~30% groundcover. A fallow knockdown application of glufosinate (Biffo at 5 L/ha) was applied prior to application A to control established weeds (flaxleaf fleabane, slender celery and African turnip weed). The knockdown application provided good control of all established weeds. Pre-plant treatments (application A) were applied 5 days prior to sowing. Sowing was conducted using a single disc planter on 1 m row spacings at 55 kg/ha. Post sowing pre-emergent treatments (application B) were applied 5 days after planting (5 DAP). Application B was delayed by a pump breakdown. The first rainfall recorded at the site after trial commencement was ~35 mm at 23 to 24 DAA. Chickpea emergence was assessed at 23 DAP (28 DAA). There were no significant differences for emergence with ~10-12 plants/m2 in all treatments. There were no visual crop effects from any treatment. Low levels of flaxleaf fleabane, slender celery and common sowthistle were apparent at the crop emergence assessment. These weeds were at ~3-4 leaf growth stages and expected to have germinated on a ~23 mm rainfall event that occurred 7 to 9 days prior to planting. Weed assessment was delayed to allow a new emergence of weeds from the in-crop rainfall. An additional 36 mm of rainfall was recorded ~two weeks later. A weed count was conducted at 63 DAA, following a total of ~71 mm of in-crop rainfall. Weed density was <1 plant/m2 for all species with most weeds at early stem elongation and no seedlings present. All treatments containing Balance significantly reduced flaxleaf fleabane counts by ~80-100%. Terrain followed by Balance, Balance alone and Balance + Terbyne Xtreme all provided >95% control. Terrain followed by Terbyne Xtreme was the only other treatment to significantly reduce fleabane counts (~63%). All treatments containing Balance significantly reduced common sowthistle counts by >95%. Reflex (IBS) or Terrain followed by Terbyne Xtreme, Reflex 1250 mL/ha alone (PSPE) and Terbyne Xtreme + Reflex (PSPE) also reduced sowthistle counts by >95%. Slender celery counts were only significant at the p=0.10 level. Reflex (IBS) or Terrain followed by Balance, Balance alone or Balance + Reflex 1250 mL/ha (PSPE) were the only treatments to ‘trend’ to reduced numbers of slender celery. In this situation, all treatments demonstrated good crop safety. Weed densities were very low despite >70 mm of rainfall between planting and assessment. The weed growth stages indicated germination and emergence was initiated from rainfall shortly prior to trial establishment. This may have reduced residual efficacy of products that require incorporation prior to weed germination. Under these conditions, Balance provided the most effective control of all weed species present, with no significant improvement from any treatment compared to Balance alone. None of the Group 14 herbicides alone provided significant weed control when applied prior to planting although Reflex 1250 mL/ha (PSPE) significantly reduced common sowthistle counts.

Paradoxa grass (Phalaris paradoxa) is an important weed of winter crops, particularly in seasons when wet conditions occur in late autumn and early winter. Improved understanding of the potential for residual paradoxa grass management is needed due to increasing levels of Group 1 (A) and 2 (B) post-emergent herbicide resistance.

This project was developed to evaluate a range of residual herbicides for paradoxa grass (phalaris) control in wheat. However, a mix-up occurred at sowing with the paddock planted to barley rather than the planned wheat crop.

Although Sakura and Luximax are not registered for use in barley, the trial was continued to generate efficacy data on paradoxa grass but also evaluate crop safety in barley. All of the herbicides applied have annual ryegrass control registrations with three of them having paradoxa grass control claims when applied at planting in wheat: Sakura, TriflurX and Mateno Complete. Overwatch has a paradoxa grass suppression claim when applied at planting. 

The trial was conducted in a paddock near Bellata in Northern NSW that was fallowed from faba beans in 2020. Stubble levels were low and the paddock was sown to LRPB Lancer wheat in early May.
The majority of herbicide treatments were applied in late April and incorporated by sowing (IBS) 5 days later using a John Deere single disc planter on 38 cm row spacings. Rainfall totaling 11 mm was recorded 3-4 days after planting (3-4 DAP) with an additional 7 mm within the first fortnight. One herbicide was applied as a post sowing pre-emergent (PSPE) split application, 5 days after sowing and the remaining 3 treatments applied at an early post-emergent timing in wheat, at ~4 leaf crop stage.
Wheat establishment was assessed at 12 DAP when a majority of plants were already at ~1-2 leaf stage. The untreated population was ~96 plants/m2. Severe damage to crop emergence was apparent from a number of herbicides.
Treatments containing trifluralin (TriflurX or Bolta Duo) caused the greatest damage and reduced crop emergence by >90% (0-8 plants/m2). Rifle 440 (pendimethalin) and Luximax (cinmethylin) had less impact but still reduced emergence by ~50-60% (50 and 37 plants/m2). Diablo Duo (triallate and prosulfocarb) reduced emergence by ~15% (82 plants/m2). No other treatment had a significant impact on crop emergence although there was a non-significant trend to a ~10% reduction in emergence from both Boxer Gold (s-metolachlor plus prosulfocarb) treatments and Overwatch (bixlozone). There was no effect on crop emergence from Sakura or Dual Gold. A second assessment of emergence was not conducted, as there was no apparent change in crop emergence at later inspections.
Trace levels of paradoxa grass were apparent at 23 DAP when the in-crop treatments were applied but with no detection in the untreated. Paradoxa grass control was assessed in late June at 59 DAP with a density of ~0.7 plants/m2 in the untreated. All herbicides significantly reduced the weed counts under a low paradoxa grass density. Sakura, the split application of Boxer Gold, Luximax and all treatments containing trifluralin reduced paradoxa grass counts by >90%. Arcade 3 L/ha and Mateno Complete applied at 23 DAP also reduced paradoxa counts by >90%.
All treatments provided useful levels of suppression or control of paradoxa grass for ~3-7 weeks after application. All herbicides with paradoxa grass control claims provided >90% reduction in counts with encouraging activity from the split application of Boxer Gold, Luximax and Arcade 3 L/ha applied 23 DAP.
An effective commercial knockdown spray was applied shortly after the 59 DAP assessment. The site was inspected in August and October with no new paradoxa grass emergence in the untreated but trace levels where severe crop damage had occurred.
This trial however was an example where residual herbicide crop safety was very poor. The actual cause is unclear but may be due to a combination of early planting with very rapid seedling development (wheat to 2 leaf by 12 DAP) and the use of a single disc planter which failed to remove adequate soil from the planting furrow. Depth of planting was unfortunately not assessed but the rapid crop emergence would suggest planting seed was relatively shallow. Rainfall after planting was obviously a factor but the amounts were relatively low with ~8 mm at 3 DAP and ~3 mm at 4 DAP.
In this situation, with low paradoxa grass density, the treatments with the best combination of crop safety and paradoxa grass efficacy were Sakura, Mateno Complete and Arcade 3 L/ha.

Paradoxa grass (Phalaris paradoxa) is an important weed of winter crops, particularly in seasons when wet conditions occur in late autumn and early winter. Improved understanding of the potential for residual paradoxa grass management is needed due to increasing levels of Group 1 (A) and 2 (B) post-emergent herbicide resistance.
This project evaluated a range of residual herbicides with existing registrations for use in wheat. Three of the herbicides have paradoxa grass control claims when applied at planting in wheat: Sakura, TriflurX and Mateno Complete and Overwatch has a suppression claim.

Despite the trial being established in a paddock with a history of FTR, common sowthistle was the only weed to emerge over thefollowing 5 months. No data was generated on residual herbicide efficacy against FTR

This trial was established to evaluate the residual control of Feathertop Rhodes (FTR) grass in wheat. Stubble levels were extremely low with the paddock long fallowed from sorghum in 2019/20.
The majority of treatments were applied 3 days prior to planting (-3 DAP) and incorporated by sowing (IBS) using a commercial disc planter on 28cm row spacing. The post sowing pre-emergent treatment (PSPE) was applied 4 days after planting. No rainfall was recorded between the IBS and PSPE applications with ~24 mm recorded in the first 9 days after the PSPE application. The in-crop application was applied at a crop stage of 2-4 tillers, 57 days after planting (57 DAP) and received ~11mm of rain the following day.
A total of 175mm was received during the 5-month duration of the trial. Monthly totals of less than 10mm of rain were recorded in August and September with a total of ~65mm in October.
Wheat establishment was assessed at 18 DAP with ~104 pl

This trial was established to screen potential options for the residual control of tall fleabane in fallow. Stubble levels were very high (~95%) following harvest of the 2021 wheat crop. The trial was established in the second week of February 2022, ~ 1 week after the site recorded ~57 mm of rain. Total rainfall of ~530 mm was received during the 6 months that the trial was conducted with ~14 mm of rain received ~9 days after residual herbicide application.
An initial assessment was conducted 31 days after application (31 DAA) with very low weed numbers present despite ~170 mm of rainfall being received. Seedling common sowthistle (~1-3 leaf) were present at ~0.2/m2. Although there were no common sowthistle present in treatments that included Valor, Voraxor, Terbyne Xtreme, the experimental Group 14 herbicide or Tordon 75-D, the untreated weed density was too variable and low to show significant differences.
During the following 7 weeks, an additional ~107 mm of rainfall was recorded with a second weed assessment made at 80 DAA. Common sowthistle densities had increased in the untreated to ~0.6/m2. The majority of sowthistle were at the 4-7 leaf stage but advanced plants weeds were at early flowering. No treatment provided complete control of common sowthistle but with >80% reduction in numbers where Valor was used alone or in mixture with Impose. Only Valor 280 g/ha provided a significant reduction in common sowthistle counts compared to the untreated. Neither Dual Gold alone or the experimental Group 27 herbicide showed any suppression of common sowthistle numbers, at either assessment.
Low fleabane numbers were present at 80 DAA with untreated populations of tall fleabane at 0.2/m2 and flaxleaf fleabane at 1.7/m2. There were no significant differences for either species.
A new cohort of tall fleabane was present 3 months later when a final count of weeds was made at 172 DAA. An additional 254 mm of rain had been recorded between assessments 2 and 3. Although tall fleabane counts were still low, there was no apparent effect from any herbicide.
At this site, with very high levels of groundcover from the 2021 wheat harvest and ~170 mm of rainfall in the first month after application, no herbicide showed useful residual activity against either tall or flaxleaf fleabane. Valor 280 g/ha was the only treatment to provide significant control of a trace population of common sowthistle at 80 DAA.

Ally applied as per label recommendations with a 9 month plant back period for pulses and canola grown on alkaline soils did not appear to have a negative effect on the growth of chickpeas, field peas, lentils, faba beans and canola.

In 1978, a residual value trial in which it is possible to compare the effectiveness of previuos applied Mn with cuuently applied Mn.  The Mn sulfate at 15, 30 & 60 kg/ha in 1978 produced maximum seed yield. The 15 & 30 kg Mn sulfate applied in 1982 produced the same maximum seed yield as Mn applied in 1978.  However, the 15 kg/ha of Mn sulfate applied in 1978 & 1982 still resulted in 11 - 16% split seed compared to the nil Mn that had 40% split seed. THe 30 kg Mn sul /ha reduced split seed to <5%.

The Mn concentration in whole shoot was 34 mg/kg; indicating Mn deficiency The Mn concentration in whole shoots with 15 kg Mn sul/ha was similar (80 mg/kg) for 1978 and 1982 applications.

THese results suggest that the residual value of soil applied Mn is greater than originally thought 

• Tested effect of rates, methods of application and residual effects of zinc oxide on hybrid maize XL45.
• Zinc was either broadcast or drilled at initial rates of 0, 5.6, 11.3 or 38 kg Zn/ha and 0 or 5.6 kg Zn/ha in subsequent seasons.
• In most seasons, treatment with zinc almost doubled grain yields.
• Broadcasting and working in was more effective than drilling zinc with the fertilizer.
• Residual effects of the initial 5.6, 11.2 and 38 kg Zn remained evident throughout the 6 years and the higher rates continued to produce highest yields.

Rates nil to 5 kg Zn/ha applied in 1970. Results for 1977.

Zn applied in 1970 barely detectable although application of plain super at 250 kg/ha /yr since 1970 maintain Zn levels for near maximum yield of pasture..

The author indicated the following:  

Suggestion that results indicated need to reassess the Zn requirement of a wide on inherently Zn deficient soils. This is particularly so in the absence of Zn via the Zn impurities in super from traditional sources of rock phosphate. It maybe highly likely that some future date we may have to rely on low Zn containing Zn phosphates .  Unless more information is obtained in advanced there could be serious losses due to Zn deficiency some time in the future.

Residual effects from soil nitrogen can be observed in the following cereal crop whcih makes a good case for utilising pulse innoculants

• Residual subsoil zinc improved root growth and grain yield of wheat in a pot experiment.
• Canola genotypes did not differ in their effects on the following wheat.
• A greater proportion of wheat zinc was located in grain where subsoils had received zinc (but it should be noted that these pots had received 3 times the total zinc of the surface zinc pots).

Residual herbicides can be an effective management tool in providing an extended period of weed control but careful consideration must be given to potential crop selection limitations, or crop loss, that their application may impose.

1. Terbyne® Xtreme® and Valor® provided the best residual control of common sowthistle as stand-alone residual herbicides and as mix partners with ‘grass active’ herbicides.
2. Group K, Group D and Flame® provided the best residual control of grass weeds as standalone residual herbicides and as mix partners.
3. Herbicide mixtures provided improved control over individual products and are likely to provide more wide-spectrum control of a range of weed species.

• This trial yielded 3.4 t/ha without fertiliser but there were still good responses to nitrogen (N) and phosphorus (P). The application of both nutrients increased yields up to 4.5 t/ha.
• There was a 0.6 t/ha response to 80 kg N/ha and a 0.7 t/ha response to 24 kg P/ha.
• 24 kg P/ha applied in both years produced 0.4 to 0.5 t/ha more than where 16 kg P/ha applied both years.
• Residual responses to N and P applied in 2011 were not significant.
• NS 41 applications increased protein from about 12.3% to 13.3%. Hectolitre weights were about 77 kg/hl and screenings averaged 1%.
• The most profitable treatment over the two years of the trial was 24 kg/ha (136 kg/ha Double Phos) applied both years.

• Residual effects of high rates of nitrogen, sulfur and phosphorus applied to canola could be detected in soil tests prior to seeding wheat in the following season.
• Nitrogen applied to the wheat crop had a much larger impact (1 t/ha grain yield increase) than carryover effects of nitrogen applied to the canola crop (up to 0.6% grain protein concentration increase).
• Phosphorus rates applied to canola influenced the yield of the following wheat crop only when no P was applied to the wheat, with no difference in yield when 27 kg P/ha was applied at seeding of the wheat.
• Growers in WA’s high rainfall zone are unlikely to see meaningful carryover effects in the cereal phase from high rates of nutrition applied to canola the year prior. They should, therefore, continue to focus on expected responses in the current year only when determining the most profitable rates of fertiliser to apply to their crops.

• P fertilisers applied in 2006 did not improve grain yield in 2007, even at the high P rate (18 kg P/ha).
• In terms of residual value, there was no difference between granular and fluid P.
• 2007 applied fluid P (TGMAP) at 6 kg P/ha increased dry matter at GS30 from fresh granular P and control treatments.
• Soil testing is a useful tool for estimating P status in the soil.

The trial was conducted in a paddock sown to wheat in 2020. Cereal stubble levels were high with visual assessment indicating ~70% groundcover prior to trial initiation.
Ten treatments were applied at the start of June, and 7 days later incorporated by sowing (IBS) using a commercial single disc planter on 50 cm row spacing. The post sowing pre-emergent treatments (PSPE) were applied directly after planting. Rainfall of ~5 mm was received 3 days after IBS application with ~15mm recorded in the first week after planting/ PSPE application. Total rainfall of only ~110 mm was received in the 4 months after planting. Inspection and assessment for weed emergence was conducted at ~4-6 week intervals from early July. The trial was concluded in early November.
Chickpea establishment was assessed at 30 days after planting (30 DAP) with ~22 plants/m2 in the untreated plots. There was no apparent effect on emergence from any herbicide treatment and no visual crop effects. No weeds were present at this assessment.
Insufficient paradoxa grass emerged during the trial to allow assessment. Common sowthistle (Sonchus oleraceus) was the only weed to emerge in sufficient numbers to allow a useful evaluation of residual efficacy.
Residual common sowthistle control was assessed at both 66 and 87 DAP. Trace levels were present at 66 DAP with <1 sowthistle/10m2 in the untreated, mainly at a 2 to 5 leaf stage. Significant (and complete control) was provided by Balance + Simazine, Balance + Terbyne Xtreme and the experimental treatment. Balance alone and Outlook were the only other treatments to provide >90% control.
By 87 DAP, the untreated sowthistle population was ~0.3/m2, mainly at the large rosette stage. Balance, Balance + Simazine, Balance + Terbyne, the experimental treatment and Outlook all provided significant control and reduced populations by >98%.
Under low weed densities, the commercial standards of Balance alone or in a tank mixture with either Simazine or Terbyne Xtreme provided complete common sowthistle control of populations emerging ~5 to 10 weeks after application. Complete control was also achieved by the experimental herbicide. Outlook also provided significant levels of control of common sowthistle but does not have label claim for this weed in chickpeas. No data was generated on the residual control of paradoxa grass.

2020 Key message:

• The ability to make the best use possible out of rainfall and stored soil moisture continues to be the largest driver of crop and pasture production on the Eyre Peninsula.
• Being able to measure what plant-available soil moisture is present at any time of the year, not only at soil moisture probe points but across the landscape offers the potential to improve productivity and limit risk.
• In the next 12 months, tools such as an improved platform (website/app) to display soil moisture probe information will be rolled out.
•  
• 2021 Key message
• Out of season rainfall and stored soil moisture were found to be key factors in driving grain yields across most farming systems on the Eyre Peninsula in 2021. 
• Collating and interpreting information from a range of sources including plant available water, previous grain yields and soil testing across the landscape can maximise returns and reduce risk. 
• Improving knowledge of soil characteristics can add considerable valueto monitoring soil moistue probes.  

• Grain shattering is a significant cause of grain yield loss in wheat, accounting for 11–13% of the variability in grain yield in this experiment.

• Genetic variation exists for grain shattering in Australian wheat varieties.

• However, grain shattering is also controlled by the environment, and this will influence choice of variety.

• Almost 20% of all stored grain insects collected had strong resistance to phosphine.
• Rusty grain beetle resistance is the most serious, as it is beyond label rates to control.
• Strong resistance in lesser grain borer is the main problem in New South Wales; rice weevil in South Australia.

• Approximately 3% of all stored grain insects collected had strong resistance to phosphine – a marked reduction from 18% in 2016.
• Improved hygiene is the probable reason for the observed reduction in resistance.
• Rusty grain beetle resistance remains the most serious issue as it is not controlled by current label rates.

• It was not surprising that no response to sulphur was obtained, when we consider that the KCI sulphur level in the soil rose from 5-7 mg/kg before bed forming to 16 mg/kg after bed forming. 
• For further discussion please see the attached trial report.

  Key findings:

Yield in the presence of crown rot was generally barley > bread wheat > durum across both sowing times, but significant differences were evident between varieties.

• Barley, bread wheat and durum varieties differ in their extent of yield loss from crown rot and their actual yield and grain quality (screenings) in the presence of this disease.
• However, all varieties are susceptible to crown rot infection and will not significantly reduce inoculum levels for subsequent crops. Variety choice is not a sole solution to crown rot.

Conclusions

• Sowing date and variety maturity choice is a balance between frost risk and terminal heat stress in the northern grain region. Both can have a significant impact on grain yield. No frost damage was evident at this site in 2014 with either sowing time but terminal heat stress did occur which was more severe during grain filling with the second sowing time. A three week delay in sowing time resulted in an average 24% reduction in yield across the winter cereal entries.  Later sowing pushed grain-fill too far into hotter conditions. This can reduce yield by itself but if there is also an underlying issue with crown rot then delayed sowing significantly exacerbates the expression of this disease with negative impacts on both yield and grain quality.

  Varieties do differ in their extent of yield loss from crown rot and in their relative yield in the presence of high levels of infection, which is often referred to as tolerance. This is a function of a varieties level of partial resistance to infection but appears to also interact with its environmental adaptation and maturity relative to the timing of stress (moisture and heat) which exacerbates the expression of crown rot. Generally quicker maturing barley, durum and bread wheat entries were higher yielding in the presence of crown rot infection in this trial. This does not necessarily mean that these varieties have improved levels of resistance to crown rot infection but rather their quicker maturity allowed them to minimize stress during grain filling relative to longer season entries, reducing the expression of crown rot.

  If forced into planting a cereal crop in a high crown rot risk situation then some barley varieties may provide a yield advantage over bread wheat in that season, as long as early stress does not occur. Some of the newer bread wheat varieties do appear to be closing this gap to some extent. Barley tends to yield better in the presence of crown rot infection due to its earlier maturity relative to bread wheat, providing an escape mechanism which reduces its exposure to moisture stress during the critical grain filling stage. However, a key message is that this decision is only potentially maximising profit in the current season. Growing barley over bread wheat will not assist with the reduction of crown rot inoculum levels as barley is very susceptible to infection. Significant yield loss is still occurring in the best of the barley and bread wheat varieties in the presence of high crown rot infection. Variety selection can improve yield in the presence of crown rot, though all varieties still suffer yield loss, which can maximise profit in the current season but this will not reduce inoculum levels for subsequent crops. Winter cereal crop and variety choice is therefore not the sole solution to crown rot but rather just one element of an integrated management strategy to limit losses from this disease.

• 10 chickpea genotypes were grown in the field with and without added zinc.
• Zinc sulphate was applied to the soil at sowing and later as a foliar spray at the start of flowering.
• Zinc fertilisation increase shoot dry matter by 13% at maturity.
• There were differences between cultivars in zinc efficiency.
• Gains in yield by improved to sink efficiency are possible in chickpeas.
•  The ranking of cultivars was consistent between sites and in pot studies in the glasshouse.
•  Significant responses to zinc fertiliser confirmed that zinc deficiency was a limitation to chickpea yield.

• Chickpea seed yield responded to 50 kg N/ha applied 8 weeks after sowing at Grass Patch in 2020
• Higher rates did not increase yields when applied at 8 weeks after sowing or in a split application at 8 and 12 weeks after sowing.
• Within plot variation resulted in no significant difference in the gross margin.

• Chickpea seed yield responded to 25-50 kg N/ha applied 18 weeks after sowing at Ridely in 2020
• Yield responses were not large enough to pay for the cost on applied nitrogen.
• Kabuli variety Gen090 produced similar yields to desi variety CBA Captain

• The critical zinc concentration in shoots ranged from 22 to 29 mg /kilogram across the 5 durum varieties.
• There was no difference in shoot zinc concentration of the 5 varieties within any of the zinc treatments, ranging from 0.025 to 5 mg / kilogram of soil.
• There was some evidence that zinc sensitive genotypes were more likely to suffer from crown rot.

• Applying 100 kg N/ha 8 weeks after sowing increased yield, but did not lead to increased gross margins
• Trial site was flooded in August – treat results with caution

• The Italian ryegrass responded well to phosphorus additions in the range of 15-60 kg P/ha and required the higher rates to be applied unless nitrogen, potassium and sulphur were also included.
• In regard to the addition of potassium, the relatively wet year meant there was unexpectedly no negative affect on plant establishment by banding potassium fertiliser in the soil at sowing which is generally not recommended.

• Applying nitrogen to lentil had no positive effect in 2020

Potassium levels are low in this soil and this site should have been responsive to applied potassium, however due to seasonal and soil conditions there where no differences between treatments in this trial. The very dry June-August had a marked impact on crop growth, particularly tillering. This can be seen by the lack of differences in the head counts taken in September. Very hot conditions in early August also affected flowering in wheat and limited any response in grain yeild with later rains. Soil penetrometer readings in the paddock near the trial site showed hard pan and this in conjunction with the pH and Aluminium levels below 10cm would have restricted root growth and limited the wheat plants ability to access soil miosture at depth during the dry winter period. Without yield responses to applied treatments, crop return decreased as fertiliser rates increased.