• Changes in farming practices in the past 15 years have increased crop disease pressure in southern NSW.
• Annual crop surveys are important for monitoring disease incidence and severity between districts and years. They also identify emerging disease issues and provide forewarning of potential problems.
• Sclerotinia diseases were widespread in broadleaf crops across the region in 2020, especially in narrow-leaf lupin and canola crops. This will have implications in 2021 and beyond.
• Blackleg was observed in every canola crop assessed as part of the integrated disease management (IDM) crop survey.
• Canola sown into a double break scenario will potentially require pre-emptive management to minimise disease risk.
• The decision to use fungicides is not always clear and should be assessed every year, depending on your crop’s disease risk profile.

• The survey received 224 responses from growers aligned with the different farming systems groups participating in this project.
• 39% of the grower respondents identified barley grass as having a medium to high impact on their cropping systems.
• 40% of the grower respondents feel that barley grass emergence patterns have changed over the last 10 years and that it now emerges later in the season.

51% of growers thought barley grass had become more common in their cropping paddocks. Some of the factors responsible for the increase in barley grass include delayed emergence and early seed-set, low efficacy of pre-emergence herbicides, particularly during dry starts to seasons, resistance to group A herbicides, continuous cereals in the system and wide crop row spacing

• Substantially better brome control and seed set reduction is possible by using pre-emergence options other than trifluralin.
• The costly Sakura+Avadex treatment is likely to be the most effective.
• Consistency of performance of all pre-emergence herbicides for brome remains a problem
• On-row seeding on non-wetting sand showed that it can substantially improve early crop emergence.
• One reason for this is the likely wetter surface soil in rows at time of seeding.
• Seasonal conditions such as the long-wet season of 2016 will affect efficacy of both pre-emergence herbicides and the impact of additional crop competition on brome seed set suppression.
• Maintaining low seedbanks and having alternative options for weed seed control when faced with a risk of ‘blowouts’ in brome seed set is important given the chance of particularly poor control in some seasons.

• Substantially better brome control and seed set reduction is possible with pre-emergence options other than trifluralin.
• The costly Sakura+Avadex treatment is likely to be the most effective.
• Consistency of performance of all pre-emergence herbicides for brome remains a problem
• On-row seeding on non-wetting sand can substantially improve early crop emergence in part due to increased surface soil water accumulation in rows at time of seeding.
• Seasonal conditions such as the long wet season of 2016 will affect efficacy of both pre-emergence herbicides and the impact of additional crop competition on brome seed set suppression.
• Maintaining low seedbanks and having alternative options for weed seed control when faced with a risk of ‘blowouts’ in brome seed set is important given the chance of particularly poor control in some seasons.

• The later seeding had very poor crop establishment, resulting in significantly higher brome seed production (115% more panicles) than early seeding, but seeding time did not interact with herbicide treatment effects.
• Only the treatments including Sakura resulted in significantly (P<0.01) better brome control than trifluralin alone (measured by number of panicles/m2).
• Sakura alone resulted in 55% less brome panicles than trifluralin alone, and Sakura + Avadex resulted in 72% less brome panicles than trifluralin alone.
• Sakura’s extended residual soil activity, which can restrict root growth of brome, combined with the dry spring, was probably responsible for the reduced seed set.
• Substantially better brome control and seedset reduction is possible by using pre-emergence options other than trifluralin. The additional herbicide cost needs to be evaluated against the better level of control, including the longer-term seedbank benefits.

• The herbicide treatment had a significant effect on annual ryegrass (ARG) plant density. Trifluralin only reduced ARG spike density by 20% compared to the untreated control, whereas Boxer Gold caused a 73% reduction in ARG spike density.
• Barley sown on 25 cm row spacing resulted in a 38% less ARG seed production compared to the 37.5 cm row spacing treatment.
• Barley sown using the splitter seed boot treatment had 32% lower ARG seed production than the narrow seed boot treatment.
• It was still profitable to control ARG with effective herbicide treatments. Based on cash grain price of feed barley of $250/t in 2019, Trifluralin would be expected to increase the gross margin by $32/ha as compared $71/ha increase for Boxer Gold.

 

The herbicide treatment had a significant effect on annual ryegrass (ARG) plant density (P<0.001) in this field trial at Minnipa. Favourable rain events in May were highly suitable for the activity of both pre-emergent herbicides investigated in this trial. Averaged across the row spacing and seed boot treatments, Trifluralin and Boxer Gold reduced ARG plant density by 20% and 90%, respectively. The density of ARG spikes was significantly influenced by the row spacing (P<0.001), seed boot treatment (P=0.027), and the herbicide treatment (P<0.001). The 25cm row spacing had 20% lower ARG spike density than the 37.5cm row spacing treatment. The splitter seed boot treatment had 12% lower ARG spike density than the narrow seed boot treatment. Trifluralin only reduced ARG spike density by 20% compared to the untreated control, whereas Boxer Gold caused a 73% reduction in ARG spike density. ARG seed production was also significantly affected by the row spacing (P=0.003), seed boot (P=0.01), and the herbicide treatment (P<0.001). The normal (25 cm) row spacing set 38% less seed than the wide row spacing. The splitter seed boot treatment also had 32% lower ARG seed set compared to the narrow seed boot. ARG produced 4792 seeds/m2 in the untreated control, which was reduced by 11% by Trifluralin and 69% by Boxer Gold. Presence of ARG at 262 plants/m2 in the untreated control, reduced barley grain yield by 8% compared to Trifluralin or 16% compared to Boxer Gold. However, it was still profitable to control ARG with effective herbicide treatments. Based on cash grain price of Feed Barley of $250/t in 2019, Trifluralin would be expected to increase the gross margin by $32/ha as compared $71/ha increase for Boxer Gold.

• Weed control in Broad beans in the SE of South Australia requires increased research to adapt new strategies to minimise resistance to herbicide technologies.
• Conmurra Trial Site was extremely clean in 2013 with lesser loosestrife being the only major weed observed.
• All treatments except Triflur X, Terbyne PSPE, F8142/6 and Magister significantly increased yield when compared to the untreated control.
• Triflur X, Terbyne PSPE, F8142/6 and Magister were not significantly different in yield when compared to the untreated control.
• Ensure to read and follow herbicide label before the application.
• Trial Photos Can Be found on the Mackillop Website.

• The disc machine had much less variation in seed placement than the tyne.
• The depth of incorporation with the single disc seeder increased slightly with speed, although speed of sowing did not significantly improve weed control.
• Crop growth was not affected by the speed of sowing with discs as hypothesized but there was a significant difference between the tyne and disc seeded treatments. The limited vigour of the wheat seedling sown by the disc seeder is probably the reason for generally lower yields than tyne sown plots. It is not clear whether reduced vigour was due to weed competition or herbicide toxicity as these factors weren’t tested separately in this trial. 
• For further detials, see attached trial report.

• Sowing canola early (6 April) on 200 mm applied water reduced the time to the start of flowering by up to two weeks, compared with a later sowing (7 May).
• Significant yield increases were recorded across all varieties (for both sowing dates) where 200 mm water was applied pre-sowing, compared with 70 mm and 0 mm.
• The highest yield resulted from sowing a mid season hybrid (Pioneer® 45Y91 (CL)) early on 200 mm applied water.
• Sowing canola early on 200 mm applied water yielded around 900 kg/ha more than sowing later with the same amount of applied water, averaged across all varieties.

• Increasing siphon pipe diameter used for flood irrigation, from 42 mm to 63 mm halved irrigation time, reduced the amount of water applied per irrigation, and increased cotton lint yield and lint quality.
• The longer irrigation time increased soil water content for up to a week post irrigation, and likely led to waterlogging effects on cotton plant growth.
• The maximum daily nitrous oxide (N2O) emissions occurred in response to the first irrigation event after pre-plant nitrogen (N) application and continued for more than a week after irrigation.
• The highest N2O emissions in each plot came from the non-irrigated side of the plant bed where surface soil nitrate concentrations were also highest – despite pre-plant N fertiliser being applied evenly to both sides of the plant bed.
• Postharvest, excess soil nitrate was found to depth in the non-irrigated side of the plant bed, indicating that nitrate moved both sideways and downwards during the season.
   

In 2019, the three trial sites experienced vastly different rainfall and crop germination patterns. The Kojonup site had good soil moisture throughout the growing season resulting in a rapid crop germination. The York and Miling sites however were seeded into completely dry conditions with the wheat germination in the TOS 1 treatments occurring more than six weeks after seeding. The bioassay experiment showed that at all sites, Sakura was the most persistent herbicide. This was evident in the field results where the persistence and activity of Sakura resulted in lower ryegrass emergence, lower seed production and a higher wheat yield. Furthermore, the results showed that at the Kojonup site, which was sown into excellent soil moisture, Trifluralin was also very effective.

The TOS response was variable; the first time of seeding showed better weed control and wheat yields at Miling and York whereas the delayed time of seeding was advisable at the moist Kojonup site. It was also found that increasing the wheat density increased crop competition which in turn reduced ryegrass emergence, ryegrass biomass and ryegrass seed production for all herbicide treatments studied. 

• A combination of dry sowing and a pre-emergent herbicide choice yields greater than the standard sowing time.
• The seed production of ARG at the end of the season correlates with the pre-emergent herbicide soil persistence.
• Increasing crop seeding rates may affect ARG seed production at some sites.

• 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.

Trifluralin appears to be the best pre-emergent ryegrass herbicide for wheat.

Trifluralin and related Group D herbicides are effective in controlling Group A herbicide resistant ryegrass, however when they are consistently used without other control practices resistance will develop. Ryegrass with Group D (trifluralin) resistance is already common in some areas.

Differences in trifluralin tolerances exist between different wheat varieties, however the differences were not consistent. Over three years of trial work Silverstar was intolerant to trifluralin in one year (30% yield loss at Triflur480 2.4L/ha IBS in 1998) and tolerant in 1999 and 2000. In 2000 only Yitpi suffered a yield loss (20% yield loss at Triflur480 2.4L/ha IBS). There are no differences in tolerance when applying trifluralin immediately prior to sowing or post sowing pre-emergent as long as the trifluralin is not incorporated into the sowing band. Trifluralin residues in grain were below the Minimum Residue Level (less than 0.05ppm) for the plots with trifluralin used at the registered rate or at the high application rate (Triflur480 2.4L/ha). Trifluralin is registered at 0.8L/ha of Triflur480 applied at least 7 days prior to sowing. NuFarm have applied to the NRA for changes to the Triflur480 label - changes relate to higher rates for use in minimum tillage.

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.

• Vegetable beetle and slater activity is correlated to high relative humidity, mild temperatures and time of day, and that these conditions overlap with other crop emergence pests such as conical snails.
• Vegetable beetles and slater movement was not correlated with soil moisture content, unlike conical snails.
• There may be a wider window of opportunity to apply chemical controls to target these pests pre-sowing especially in dry sowing situations. Whereas when baiting for snails, efficacy is improved when baits are applied immediately following rain when the soil surface is moist and there is high relative humidity overnight.

• Velocity and Precept selective herbicides are based on a new active pyrasulfotole.
• This is a new mode of action on broadleaf weeds in cereals in Australia (Group H).
• Velocity and Precept showed excellent crop safety.
• Broad spectrum and reliable broadleaf weed control.

• Triflur and Roundup CT applied pre-sowing produced the best yield and gross margin result, some other treatments were statistically similar.
• All 4 rates of Diuron produced the same yield and gross margin.
• The best timing for weed control to maximize yield and gross margin is prior to sowing.

There are still many answers required before we can be confident on how to manage this important and expensive input to our farming systems.

• There are still many answers required before we can be confident on how to manage this important and expensive input to our farming systems.
• There is little chance that we can work out a profitable N management system if we do not know what happens to applied nitrogen in our cropping soils.

May 4th sown Mackellar wheat produced yields in the range of 4.74 – 5.99 t/ha following canola stubble. With high soil nitrogen reserves (176 kg/ha N, 0‐90cm) recorded 2 days pre sowing, there was a small but significant response to applied nitrogen (0.43 t/ha at 50kg/ha N & 0.58 t/ha at 100kg/ha N). There was a significant advantage to nitrogen timed during stem elongation (GS30‐39) over nitrogen applied in the seedbed. This advantage was evident in both single and split applications between which there was
no difference.

• Our standard package of 100 kg 18:20/ha at seeding under the seed row (to avoid fertiliser toxicity), Jockey-treated seed, endosulfan and simazine pre-seeding, a follow up spray of atrazine and a grass herbicide mid-season, and two top-ups of nitrogen during the season (50 kg N/ha as broadcast urea each time) gave us a clean, high yielding and good quality crop with no pests or diseases.
• There was no evidence that extra management options provided any further benefits to canola performance (ie a fungicide spray, B fertiliser or use of a growth regulant) under the conditions of last year’s trial.
• However, it would appear that we may have been a bit generous with our N and P inputs in the standard package because we could halve the mid-season N rate and not suffer any yield or quality loss. Additionally, leaving out P altogether had little impact so a rate lower than 20 kg P/ha may have been the best compromise last year.
• There seems little reason to change from a management strategy of plenty of N at seeding (providing you can avoid seedling toxicity by separating the N and the seed) followed up by an early season top-up. Delayed aapplications of N produced yields or quality no better than our standard.

• Seeding rate had a bigger impact on wheat establishment than soil wetting agents
• High seeding rates on soils with low yield potential were sometimes a disadvantage; optimal seeding rates would need to account for yield potential as well as the degree of soil water repellence.
• Delaying sowing providing an opportunity to get a knockdown of weeds was important on water repellent soils where staggered weed germination, and reduced herbicide activity, reduces efficacy of in-crop and pre-emergent applications.
• In these trials soil wetting agents did not consistently improve wheat establishment and despite some evidence of benefits to vegetative growth this generally did not translate into a grain yield benefit.

• Despite high levels of available soil nitrogen at the start of the season (113 kg/ha N, 0 – 100 cm), there was a significant yield response to applied nitrogen. There was no yield advantage of 100kg/ha N over 50kg/ha N.
• At 50kg/ha N, there was a significant yield advantage (0.47t/ha) from application at GS33 (third node) compared to application pre-sowing.
• At 100kg/ha N, there was a significant yield advantage (0.55t/ha) from application at GS30 above seedbed application. Differences at 50kg/ha were not significant.

• Elevated temperature reduced yield by 0.3 – 0.4 t/ha per degree (°C) higher during pre- and post-flowering. •
• The effect of temperature was offset by grain number per m2 .
• Higher N rates may partially mitigate the effect of elevated temperature..

Nitrogen use has resulted in great improvements in crop yield in favourable seasons.
In dry seasons too much applied nitrogen can result in haying-off and lower yields.
Good guidelines are now available for nitrogen use to reduce the risk of crop failure resulting from applying too much fertiliser nitrogen.
The critical factors are:
• Stored soil water (control summer weeds)
• Measure how much nitrogen is in the soil prior to sowing
• Calculate nitrogen requirement from the target yield
• Do not pre-drill more than 60 kg/ha of urea in the 350mm rainfall zone (100kg/ha in the 450mm zone)
• Split applications are safer
• Topdress with urea if the soil test indicates a need, the crop is healthy, and the outlook is for an average to wet season

• A combination of Monza and Sakura applied PSPE provided the highest levels of wild oat control (68%)
• Even with good control a high weed density remained (>200 plants per square metre) which would still be expected to cause significant crop yield losses (90%)

• Sakura alone or in combination with Avadex Xtra provided the highest levels of wild oat control (75%).
• Although Sakura treatments provided the highest level of wild oat control the high weed density remaining (>50 plants per square metre) would still be expected to cause significant crop yield losses (50%).

The weather conditions in 2015 were extremely dry, and is thought that this may have impacted on the efficacy of the herbicides in this season.

• APSIM simulations, accessed through the Yield Prophet web interface, were evaluated for their ability to forecast nitrogen fertiliser responses at the canopy management trial in the Wimmera.
• Yield Prophet accurately simulated crop yield and protein for a range of nitrogen fertiliser application rates and timings.
• Yield Prophet was able to estimate likely nitrogen fertiliser responses and dollar returns during the season.
• For accurate simulations Yield Prophet requires good soil characterisation data (crop lower limit, drained upper limit and bulk density) and pre-sowing measurements of soil water and available nitrogen.

• All treatments were safe to the crop except for Sakura 118 g/ha + Sencor 150 g/ha which resulted in biomass reduction at all assessments.
• This was in part due to a couple of rows being sown into the inter row that contained herbicide which re-sulted in the death of some plants.
• This mixture would not be recommended on conventional wheat. An overall crop bio-mass rating was taken 106 DAA rated Sakura 118 g/ha as 100% with the other treatments benchmarked against it.
• The crop was water stressed at this time. Inspection of the crop heads found they were not filling to potential with small grain and empty husks common across the trial.