• Neither Cu or Zn increased grain yield
• Zinc did not reduced yield of wheat with Cu nil. Cu application gave  no yield increase without Zn applied.
• Combination of 5.5 kg Cu sulfate and 8.25 kg Cu sulfate depressd yield.
• Plainsuperphosphate and aerophos+gypsum gave maximum yield.
• .

• Zinc reduced yield of wheat with Cu nil. Cu application gave a small yield increase without Zn applied.
• Combination of 5.5 kg Cu sulfate and 1.7 kg Zn oxide gace maximum yield.
• There was no evidence that further additions of Cu and Zn was needed in subsequent years.

• Neither Zinc or Cu increased grainyield alone
• Wheat required Cu & Zn applied together.
• Combination of 5.5 kg Cu sulfate and 1.7 kg Zn oxide gace maximum yield.
• There was no evidence that further additions of Cu and Zn was needed in subsequent years.

• Cu increased with Zn or without Zn added to superphosphate.  
•  ZnO application had no consistent effect on grain with Cu applied.
• Combination of Cu Sul at 5.5 kg/ha and  nil  ZnO was required for maximum yield.
• Plain superphosphate yielded  the same as Aerophos +gypsum suggested  Zn soil was adequate.

• General location only as 3 experiments are summarised for 1967.
• Trials over 1965-1967 ; covers a range of locations for the central wheatbelt area
• Summary of 3 experiments with 4 Cu and 4 Zn levels
• Cu increased grain yield in the absence or presence of Zn.
• Cu application increased grain yield by 35 - 50%
• Zn depressed grain yield at nil Cu more in the gravels than sands
• Combination of Cu sulfate (5.5 kg Cu sulfate) and 1.6  KgZnO /ha  for maximum yield on gravel sites
• General conclusion 5.5 kg Cu sulfate and 0.8 kg/ha ZnO adequatefor sandy surfaced grey earths of the central wheatbelt of WA.

• Cu increased with Zn or without Zn added to superphosphate.  
• All Zn levels depressed yield with nil Cu other levels of ZnO application increased grain with Cu applied.
• Combination of Cu Sul at 5.5 kg/ha and 0.8 kg/ha ZnO was required for maximum yield.
• Plain superphosphate out yielded  Aerophos +gypsum suggested  Zn soil was inadequate.

• Concluded that Cu and Zn not required for wheat .
• Zn addition not required for grain yield of oats and also clover growth..

• General location only as 5 experiments are summarised for 1967.
• Trials over 1965-1967 ; covers a range of locations for the central wheatbelt area
• Combination of 4 Cu levels and 3 Zn [0.8 kg ZnO ommitted].
• Summary of  5 experiments with 4 Cu and 3 Zn levels sandy
• Cu increased grain yield in the absence or presence of Zn.
• Cu application increased grain yield by 35 - 50%
• Zn depressed grain yield at nil Cu.
• Combination of Cu sulfate (2.75kg Cu sulfate) and nil KgZnO /ha  gave the same maximum yield.

• Cu increased with or without Zn added to superphosphate.  
• Zinc oxide increased yield of wheat with Cu (2.75 & 5.5  Kg Cu sulfate/ha).
• Combination of Cu sulfate (5.5 kg Cu sulfate) and 0.8 kg Zn oxide required.
• Plain superphosphate gave higher yield than aerophos+gypsum.
• .

• Summary of 2 experimental sites 
• Cu increased with or without Zn added to superphosphate.  
• Zinc oxide increased yield of wheat with Cu (2.75 & 5.5  Kg Cu sulfate/ha).
• Combination of Cu sulfate (5.5 kg Cu sulfate) and 0.8 kg Zn oxide required.
• Plainsuperphosphate gave higher yield than aerophos+gypsum.
• .

• Summary of 2 experimental sites 
• Small additions of Cu or Zn added to superphosphate increased grain yield.  
• Zinc oxide at 3.3 kg/ha did  reduced yield of wheat with Cu (0 & 2.75 Kg Cusulfate/ha).
• Cu application at 8.25 kg Cusulfate without Zn applied decreased grain yield.
• Combination of Cu sulfate (2.75 kg Cu sulfate) and 0.8 kg Zn oxide required.
• Plainsuperphosphate gave higher yield than aerophos+gypsum gave maximum yield.
• .

• Cu increased with Zn or without Zn added to superphosphate.  
• All Zn levels followed no consistent pattern some depressed yield other levels of ZnO application increased.
• Concludedd Zn application not real & Zn had no clear reffect on grain yield.
• Combination of Cu Sul at 2.75 kg/ha and nil ZnO was requyired for maximum yield.
• Plain superphosphate yield was the sane as Aerophos +gypsum suggested  Zn soil was adequate; hence no further Zn was recommended for Oats and Clover.

• Cu increased with Zn or without Zn added to superphosphate.  
• All Zn levels depressed yield with nil Cu 2.75 & 5.5 Cu levels, particularly 3.3 kg /ha of ZnO application.
• Combination of Cu Sul at 5.5 kg/ha and nil  kg/ha ZnO or 2.75 kg Cu/ha nil Zn was required for maximum yield.
• Plain superphosphate out yielded  Aerophos +gypsum suggested  Zn soil was inadequat for oats and or clover.

• Summary of 2 experiments
• Nil Cu and Nil Zn gave equal top yield.  
• Even without Zn, CuSulfate @2.75 kg/ha slight nonsignificant increase in the growing season.
• Zn addition decrease wheat yield with no added Cu.
• Cu  at 2.75 kg Cu sulfate gave maximum yield.
• Copper deficiency of wheat and barley have been recorded in trials and farmer paddocks.
• Aerophos and plain superphosphate treatments were not significantly different.

• Cu increased grain yield in the absence or presence of Zn.
• Cu application increased grain yield by 50-60%
• Zn depressed grain yield at nil Cu and in all Cu applications
• Combination of Cu sulfate (2.75 kg Cu sulfate) and nil KgZnO /ha  for maximum yield on gravel sites
• General conclusion similar results to yellowm-brown gravel  of the central wheatbelt of WA.

• Cu increased grain yield in the absence or presence of Zn.
• Cu application increased grain yield by 50-60%
• Zn depressed grain yield at nil Cu and in all Cu applications
• Combination of Cu sulfate (2.75 kg Cu sulfate) and nil KgZnO /ha  for maximum yield on gravel sites
• General conclusion similar results to yellowm-brown gravel  of the central wheatbelt of WA.

• Cu increased grain yield in the absence or presence of Zn.
• Cu application increased grain yield by 50-60%
• Zn depressed grain yield at nil Cu and in all Cu applications
• Combination of Cu sulfate (2.75 kg Cu sulfate) and nil KgZnO /ha  for maximum yield on gravel sites
• General conclusion similar results to yellowm-brown gravel  of the central wheatbelt of WA.

• Nil Cu and Nil Zn gave equal top yield.   Zinc addition reduced yield of wheat with Cu nil. 
• Combination of 2.75 kg Cu sulfate and 1.7 kg Zn oxide gave maximum yield. The increase with 2.75 kg/ha Cu sulfate was about the same magnitude  caused by Zn addition where nil Cu was applied. Zn did not depress yield where Cu was applied.
• There was no evidence that further additions of Cu and Zn was needed for wheat in subsequent years.

• Summary of 2 experiments
• Nil Cu and Nil Zn gave equal top yield.  
• Combination of 2.75 kg Cu sulfate and 0.8 kg Zn oxide gave maximum yield.
• Copper deficiency of wheat and barley have been recorded in trials and farmer paddocks.
• Similarly, Zn deficiency in oats have been recorded in trials grown on yellow sands.

• General location only as 13 experiments are summarised for 1967.
• Trials over 1965-1967 ; covers a range of locations for the central wheatbelt area
• Gravelly sites only slightly more affected by Cu deficiency than sandy sites.
• Summary of 13 experiments with 4 Cu and 4 Zn levels
• Cu increased grain yield in the absence or presence of Zn.
• Cu application increased grain yield by 35 - 50%
• Zn depressed grain yield at nil Cu more in the gravels than sands
• Combination of Cu sulfate (8.25 kg Cu sulfate) and 1.6 or 3.3 KgZnO /ha  for maximum yield on gravel sites
• Zn nil or ZnO0.8 kg/ha Cu Sul 2.75 or 5.5 kg/ha on sandy sites
• General conclusion 5.5 kg Cu sulfate and 0.8 kg/ha ZnO adequatefor sandy and gravelly surfaced yellow earths of the central wheatbelt of WA.

• Cu & Zn either separately or in combination increased grain yield.
• Combination of 11 Kg Cu sulfate and 3.3 kg ZnO recommended
• Follow with a combination of 5.5  Kg Cu sulfate and 1.6 kg ZnO recommended in following crops.
• No information on Zn depressing yield with nil or low rates of Cu.

• Zinc reduced yield of wheat with Cu nil. Cu application gave a small yield increase without Zn applied.
• Cu & Zn apploication both required for maximum grain yield.
• Combination of 5.5 kg Cu sulfate and 1.7 kg Zn oxide grain maximum yield.
• ZnO and 1.7 kg/ha required for maximum pasture and Oat yield.
• There was no evidence that further additions of Cu and Zn was needed in subsequent years.

• Zinc reduced yield of wheat with Cu nil. Cu application gave a small yield increase without Zn applied.
• Combination of 5.5 kg Cu sulfate and 1.7 kg Zn oxide gace maximum yield.
• There was no evidence that further additions of Cu and Zn was needed in subsequent years.

• Plants grown in small pots containing Mn deficient calcareous (pH 8.5, 80% CaCO3) sand collected from Wangary, S.A with 0-50 ppm added Mn in growth room at 15°C.
• Plants harvested at approx. 4 weeks (early tillering). Also 30 wheat cultivars were screened at Wangary using plant breeders' plots (4 rows x 5 m) with a split plot application of foliar MnSO (1 kg/ha ).
• Effects of seed soaking were evaluated for wheat and barley by soaking for 6 h with 1.5% MnSO4 prior to sowing.
• Without Mn, all cultivars showed no differences in growth and Mn uptake at 4 weeks (pots) but significant differences at 8 weeks in the field. With Mn supplied either in soil or on seed large cultivar differences were apparent at 4 weeks.
• Conclude that use of Mn efficient varieties coupled with a suitable seed Mn content will lessen the need for Mn fertilisers.

• Deep ripping to 500mm increased plant biomass, tiller numbers and ultimately yield, by 500kg/ha
• There was no significant difference in weed numbers between ripped and un-ripped treatments; however, weeds in the deep ripping treatment were bigger and had more seeds, therefore potentially a greater seed bank.
• The root lesion nematode species P. neglectus population increased over the season with a ten times higher increase in un-ripped compared to ripped soil. 

• Baiting with metaldehyde baits resulted in approximately 50-60% mortality.
• Baits had most effect on snails larger then 6mm.
• This trial highlight the need for further research into the growth rates and fecundity of snails under different environmental conditions and availability of sources of food and refuges.

• Grain yield and quality was significantly reduced in all varieties when harvest was delayed. Oxford and La TrobeA suffered least yield penalty, while BassA, and FathomA had the greatest yield losses.

• Yield losses and quality downgrades ranged from $75–300/ha in lost revenue in 2016, despite overall low prices and distinction between malt and F1 grades.

• Despite seed boron concentrations being very high (>20 mg/kg) there was no detectable effect on seedling emergence or growth.
• The amount of boron in the shoots was similar irrespective of the amount of boron in the grain.
• It would appear that grain boron is not mobilised to the developing seedling.

• Just 50 kg DAP/ha knife point drilled with 70 kg/ha wheat seed is enough to reduce wheat plant  establishment.
• Wheat fertilised with DAP with seed yielded 0.5 t/ha (20%) less than wheat with DAP placed below seed in 2016.
• The addition of 35 kg urea/ha below the seed overcame the yield penalty in the DAP-with-seed plots, suggesting access to N was a driver.

• Just 50 kg DAP/ha knife point drilled with 70 kg/ha wheat seed is enough to reduce wheat plant establishment
• Wheat fertilised with DAP with seed yielded 0.5 t/ha (20%) less than wheat with DAP placed below seed in 2016. 
• The addition of 35 kg urea/ha below the seed overcame the yield penalty in the DAP-with-seed plots, suggesting access to N was a driver.

• Blackleg infection of flowers, pods, branches and upper stems can be collectively termed as upper canopy infection (UCI).

• Early flowering of canola increases the risk of UCI.

• Fungicide can reduce disease levels and increase grain yield, but does not provide full disease control.

• Matching sowing date and varietal phenology so that flowering occurs in late winter will reduce UCI.

Responses to cutting treatments in Mackellar wheat and Breakwell triticale were examined in an early sowing (March).  Frost damage was severe and both uncut treatments produced significantly lower grain yields being at mid flowering (Breakwell) and late ear emergence (Mackellar) at the time of the frosts.  Grain yields did not tend to correlate with the number of ears per m2 or grain weight.  However for both varieties the higher yields of cut treatments related to the number of grains per ear.

For trial results please see the attached trial report.

Very dry conditions during the growing season and the inherent variability with the trial site requires the results to be viewed with caution.  However these results show grazing Yerong barley during the vegetative stage of growth will have no impact on grain yield and is likely to be beneficial.  The grazing benefits to the whole farm system are considerable and the small reduction in stubble mass, although not huge is a positive outcome.

Intensive grazing at GS 30 – GS 31 (start of stem elongation) reduced grain yield compared to no grazing by an average of 37%. The greatest yield loss of 57% occurred with Monstress triticale and the lowest yield loss occurred with Amarok wheat (18%). Up to 2.1 t/ha of drymatter was available for grazing before stem elongation was reached. Yerong barley yielded the greatest drymatter pre grazing, with Brennan wheat the lowest drymatter yielding at 1.5 t/ha.

• Heat stress during the reproductive development phase significantly reduced grain yield, harvest index and oil percentage.
• Varieties respond differently to heat stress: Nuseed Diamond had the highest reduction in grain yield and oil percentage under heat stress, whereas ATR Stingray had the lowest reduction in grain yield.
• Under heat stress, seed formation is more severely affected than pod formation.
• Canola pods that appear healthy can produce less, or even no, seed, and therefore do not achieve yield potential under heat stress.

• A preliminary experiment in 2017 showed that extra heat can be applied to canola plots successfully using specially designed heat chambers.

• Heat stress of four days, applied seven days after flowering started, significantly reduced the grain yield of the flowers opening during that period.

• Four days of heat stress significantly reduced harvest index and thousand seed weight at the plot level, however, grain yield and biomass yield was not affected due to recovery during cooler nights.

• Further research is needed to extend the duration and intensity of heat stress to show differences, and for rigorous validation across different varieties.

• Yield responses were achieved when Hombre seed treatment was used at Frances and Conmurra sites in 2012.
• Crop rotation effects had a much greater impact on grain protein than whether a seed treatment was used or not.
• Reducing aphid activity reduces the risk of developing BYDV.
• Most occurrences of BYDV occur from aphid activity early in the season, so early protection is best 

• Yield responses were achieved when Hombre seed treatment was used at Frances and Conmurra sites in 2012.
• Crop rotation effects had a much greater impact on grain protein than whether a seed treatment was used or not.
• Reducing aphid activity reduces the risk of developing BYDV.
• Most occurrences of BYDV occur from aphid activity early in the season, so early protection is best 

• Yield responses were achieved when Hombre seed treatment was used at Frances and Conmurra sites in 2012
• Crop rotation effects had a much greater impact on grain protein than whether a seed treatment was used or not
• Reducing aphid activity reduces the risk of developing BYDV
• Most occurrences of BYDV occur from aphid activity early in the season, so early protection is best

Yield responses were closely related to blackleg resistance rating. Varieties with a resistance rating of 7 or greater showed low or no response to fungicide application. Varieties with a mid range rating showed large responses to fungicide.Fungicide does not totally compensate for a low resistance rating.

Three years after application of lime, soil pH (CaCl2) increased by 0.68–1.45 units at 0–10 cm depth, 0.20–0.47 units at 10–20 cm and 0.08–0.18 at 20–30 cm depth. • Lime reduced density of ryegrass by 42% and barley grass density by 67%, improved barley crop vigour by up to 13%, and increased barley grain yield by up to 7% in 2013. • Boxer Gold in 2013 season together with Sakura and simazine in previous seasons reduced annual ryegrass density by 96% and barley grass density by 99%, improved barley crop vigour by up to 15%, and increased barley grain yield by up to 16%. • Lime effect on efficacy of herbicides in controlling weeds was not evident.

Three years after application of lime, soil pH increased by about 1 unit at the top soil and 0.08-0.26 units at the sub-soil layers. • The effect of liming improved crop vigour in 2013 by up to 16% and this effect reduced wild radish density by 50%. This reduction was however not significant, most likely due to low radish densities and a high level of variability. • Velocity together with simazine in previous seasons reduced wild radish density by 98% in 2013 season and improved crop vigour by up to 16%. • Lime increased barley grain yield by up to 6% and Velocity by up to 8%. • Lime effect on herbicide efficacy to control radish in barley crop was not evident.

• Our results suggest shifting investment from nutrients to lime and cultivation and maintaining profit in the first year for the 2 sites we ran is a feasible proposition.  However, this is dependent on the soil constraints and existing soil fertility.  In this trial, it appears that the cultivation response was driven by an increase in the mineralisation rate of organic matter. The incorporation of lime did not provide any yield benefit; while the rotary spader provided adequate mixing of the lime this had no impact on growth because soil pH was already above target levels.  The yield benefit from cultivation was enough to offset the cost of the cultivation and most of the lime application, and the net margin in the year of application could be improved by reducing fertiliser rates.
•  

Our results so far suggest that there is an important interaction between year (timing and distribution of rainfall) and soil and nutrient management. There were no significant treatment effects on grain yield in 2013 and 2015, but there were in 2014 and this may be related to autumn rainfall. At the end of March, 75 and 57 mm had fallen in 2013 and 2015 respectively (Figure 3), however, only 16 mm had fallen at this time in 2014. In 2014, soil water repellence as measured in a laboratory test was significantly higher in the no-till control treatments compared to the rotary spader treatments. Seedling density in 2014 was highest in treatments that had the highest soil water repellence, however, this effect did not carry through to grain yield which was lowest in the no-till control. This trial will continue for at least one more year.

 

• There was a significant yield difference due to liming in the Magenta and Roe plots; however, the Buloke plots were not significantly different.
• Soil pH increased from 4.68 to 5.24.
• This iste had a massive radish seed bank after poor control in lupins in 2008.

• Leaves showing strongly developed symptoms of manganese deficiency or toxicity obtained from the field.
• Wherever possible parallel samples from healthy plants were also taken.
• Healthy green and chlorotic laminar tissue was dissected and manganese determined by atomic absorption spectrometry on acid digests of the wet ashed sample.
• In healthy leaves manganese is not distributed uniformly but is accumulated in the interveinal areas and the tip and margins of the blade.
• In deficient leaves this pattern is reversed and manganese concentrations are lowest in these areas.
• The distribution suggested that manganese is mobilised under severe deficiency however at luxury supply manganese behaves as an immobile element.
• The strong association between visual symptoms of manganese deficiency and toxicity and the distribution of manganese in the leaf suggest these symptoms are the product of local changes in manganese concentrations in the leaf.

• Summary of  2 experiments

• Soil extractable Cu was 0.23 mg/kg.

• Plant density were not effected by Cu or N fertiliser (29-36 plants/m of row2)

• Plant B concentrations 26 -30 mg/kg.

• Cu fertiliser had no effect on seedling density; September Dry matter (DM) (2.0 t/ha); Seed yield (1.55 t/ha) or N % in DM (3.43 % N) or N in the seed (3.6 %).

• B had no effect on %oil (41.9) or on oil yield (650 kg/ha).

• Soil extractable B Hot CaCl2 of 0.7 was adequate

  Care needs to be taken on use of borax fertilizer as toxicity was induced in canola with 0.34 to 1 kg B ha−1(3-10 kg borax ha−1) at sowing depressing seed yield, mostly by decreasing plant density. Rather than making general recommendation for B fertilizer application based on 0.01M CaCl2 soil extractable B, soil and plant analysis should be used to diagnose B deficiency and B fertilizer use limited to calcium borate or foliar borax rather than soil-applied borax on low B sands.

• Boron not required

• Rosalind (fast maturity) had the highest grain yield at all rates of applied nitrogen.
• Higher lodging at higher nitrogen rates reduced yield response to applied nitrogen in Compass, Commander and scope CL
• High spring rainfall and mild growng conditions resulted in high yields and full use of applied nitrogen

• La Trobe and Compass displayed the best combination of yield and quality traits for achieving malt specification.
• The environment, or experiment site, had a greater effect on yield than variety, nitrogen (N) rate or sowing rate. Low rainfall at Condobolin resulted in significantly lower yields than at Parkes.
• The sowing rate did not significantly affect yield above 150 plants/m2 at Condobolin or Parkes.
• Nitrogen (N) applications, in the absence of adequate rainfall, can have a negative effect on yield.

• Yield was reduced by dry and hot conditions during flowering for both times of sowing.
• Spitfire yielded highest in time of sowing 1 (1.55t/ha) and Condo yelded highest in time of sowing 2 (1.15t/ha).
• The nil nirtogen treatment yield highest (1.01 t/ha); increasing nitrogen rate decreased grain yield for both times of sowing.

• Averaged across sowing densities Djakal, N005A-80 and P176-2 yielded the highest with 3.7 t/ha, 3.8 t/ha and 3.9 t/ha respectively, while SnowyA achieved a significantly lower grain yield of 3.2 t/ha.
• Grain yield of Djakal and N005A-80 did not vary significantly between target sowing densities. Both varieties maintained high yields even at the lowest target sowing density (15 plants/m2).
• Lodging was exacerbated at higher sowing densities for all varieties except P176-2, which was consistently low across all sowing densities.
• The length of time to maturity did not vary significantly between target sowing densities for SnowyA, N005A-80 or P176-2. However, Djakal’s maturity length was extended by 4 days at the 60 plants/m2 sowing density when compared with the three lower target plant densities.

The effects of plant density (50, 125, 200 plants/m2) on growth and grain yield of early sown (March) wheat were evaluated. Early in the growing season the low density plots looked very sparse but by September had largely caught up. The trial was severely frosted at ear emergence and during flowering and average yields were only 0.5 t/ha. Yields tended to increase from 50 through to 200 plants/m2 with the highest density producing significantly greater yields than for 50 plants/m2 density. There were no differences in number of grains per ear or grain weight but there were significantly higher ears per m2 at the 200 plants/m2 density. July sown plots avoided some of the frost damage and grain yields were significantly higher.

Wheat plant density was significantly affected by the planting arrangement (P=0.027) and the herbicide treatment (P<0.001). The Ribbon seeder system had the highest wheat density (196 plants/m2) as compared to the knife-point system (180 plants/m2) and the Zero row spacing (177 plants/m2). Wheat plant density in the inter-row space in the Zero row spacing treatment was reduced by Treflan + Avadex and Boxer Gold. Annual ryegrass plant density was only affected by the herbicide treatments (P<0.001). Pre-emergent herbicide activity was much lower than expected (24-29% efficacy) and is likely to be due to extremely dry soil conditions at the site (decile 1 growing season). Similarly, the reduction in ryegrass spike density by the herbicides relative to the untreated control was low and ranged from 6 to 24%. There was no significant reduction in ryegrass seed production by the herbicide treatment, which was surprising because Sakura and Boxer Gold did reduce ryegrass spike density. Ryegrass was able to produce 18-20,000 seeds/m2 in different herbicide treatments, which highlights the poor efficacy of pre-emergent herbicide in dry conditions. Herbicide treatments had a significant effect on wheat grain yield with Sakura producing the highest yield (2.31 t/ha), closely followed by Boxer Gold (2.13 t/ha). Sakura and Boxer Gold treatments increased wheat grain yield by 29% and 19% compared to the untreated control, respectively.  These results show that ryegrass was quite competitive against wheat under the dry conditions experienced in 2018. The treatment of Sakura ($40/ha) increased wheat yield by 0.5 t/ha compared to the untreated control, which would have improved the gross margin by $150/ha.

Wheat plant density was significantly affected by the planting arrangement (P=0.012). The Ribbon seeder system had the highest wheat density (171 plants/m2) as compared to the knife-point system (156 plants/m2) and the Zero row spacing (151 plants/m2). The establishment of wheat plants in the inter-row space in the Zero row spacing treatment was strongly influenced by the pre-emergent herbicide treatment (P=0.002). Trifluralin, Avadex or Boxer Gold were higher risk pre-emergent herbicides for wheat establishment, whereas Sakura appears much safer where wheat seed is placed on the soil surface in the Zero row spacing system. Annual ryegrass (ARG) plant density was not significantly affected by the planting arrangement (P=0.513) or pre-emergent herbicide treatments (P=0.13). ARG spike density was not significantly influenced by wheat planting arrangement (P=0.185). Herbicide treatment did have a significant influence on ARG spike density (P=0.023) and ARG seed production (P=0.003). The best performing herbicide treatment of Sakura + Avadex still produced 16824 ARG seeds/m2. While this is 51% lower than the Treflan + Avadex, it will replenish the soil seedbank to a highly problematic level for the future. Wheat grain yield was significantly affected by the planting arrangement (P=0.034) and the herbicide treatments (P=0.004). Even though the differences in wheat yield were small <10% for planting arrangement and <14% for herbicide treatments, they were statistically significant.

• Soil moisture: Surface soil moisture contents were measured using a soil moisture probe on 19 May 2011- after all treatments had been applied. There had been 14mm of rain at this site in the week prior to measurement. Results ranged from 10.5-12% however there was no significant difference between treatments. The texture of the top soil (loamy sand) indicates that field capacity is typically around 14%.
• Emergence, crop vigour and biomass: Table 2 lists the in-season measurements taken at the ‘Wathingarra’ yellow sand site on the plots sown with the DBS bar. No assessment of any treatment indicated a response to Lure application. Assessments were also taken of the plots sown with the Morris bar and the rolled DBS plots however there was no significant difference for any of the seeding systems.
• Yield and grain quality: There was no significant difference in yield between the treatments in either the DBS, DBS + Rolled or the ribbon seeded plots.

 

The Hart field site has a background of pea rhizobia that are numerous, but only moderately effective. Inoculation treatment did not affect measured root parameters. Some inoculation treatments increased shoot biomass and pod number, but not grain yield or grain N content. The N benefit from the extra biomass residues is estimated to be 51 kg N/ha

The herbicide treatment had a significant effect on ARG density (P<0.001) in this field trial at Minnipa. Favourable rain events in June were highly suitable for the activity of both pre-emergent herbicides investigated in this trial. Averaged across the row spacing and SBU treatments, Boxer Gold and Sakura + Avadex reduced ARG plant density by 88% and 90%, respectively. The density of ARG spikes was significantly influenced by the herbicide treatment.  Boxer Gold reduced ARG spike density by 74% compared to the untreated control, whereas Sakura + Avadex caused 85% reduction in ARG spike density. The density of ARG spikes in Sakura + Avadex were significantly lower than in the Boxer Gold treatment. ARG seed production was also significantly affected by the herbicide treatment (P<0.001) but not by wheat row spacing (P=0.272) or seed boot design (P=0.994). ARG produced 5740 seeds/m2 in the untreated control, which was reduced by 74% by Boxer Gold and 86% by the mixture of Sakura + Avadex. Presence of ARG at 190 plants/m2 in the untreated control, reduced wheat grain yield by 11% compared to Boxer Gold or 8% compared to Sakura + Avadex. However, it was still profitable to control ARG with effective herbicide treatments. Based on cash grain price of Australian Premium Wheat (APW) of $400/t in 2018, Boxer Gold would be expected to increase the gross margin by $68/ha as compared $12/ha increase for Sakura + Avadex.

• 2 soil types compared seaparately yellow brown earths and gravels.
• % -9 experiments included in the comparisons
• Seasonal responses of 1965 & 1966 were compared
• THe Cu and Zn recommendation for 2 soil types showeed difference in combination required over the 2 seasons.
• Cu application increased grain yield by 45% in 1965 & 50% in 1966 [6 experiments in the summary]
•  
• Seasonal responses of 1966 & 1967 were compared.
• Cu increased yield by 51% in 1966 compared to 52% in 1967.
•  
• Seasonal variation in Cu requirement is not revealed
• Combination in both Cu & Zn for maximum grain yield remarkably similar across compared season and for the 2 soil types..

• Demonstrated a strong dependence of wheat seedlings linseed manganese supply.
• Real manganese uptake can only be calculated if the initial seed manganese content is known.
• Seed soaking in manganese sulphate prior to selling greatly increase the seed manganese content although less than 20% of this manganese was recovered in the seedlings after 26 days.

• Sowing wheat 75mm deep compared to 40mm deep reduced crop establishment by up to 62% and wheat yield by up to 24%.
• Within the same variety small seed was much more sensitive to deep sowing than large seed.
• Corack and Mace were the least sensitive varieties to deep sowing in terms of yield.
• Growers should endeavour to use seed larger than 35 g/thousand seeds, especially if sowing into stressful conditions.

• Yield responses to seeding density and nitrogen rate varied between the 2016 and 2017 seasons.

• BannisterA achieved the highest grain yields and had consistent grain quality in both years compared with other varieties.

• In 2017 the new milling variety KowariA had a yield advantage over benchmark variety MitikaA, and had a more stable grain quality at higher seeding and nitrogen rates.
 

• New pre-emergence herbicides provided effective control of annual ryegrass under both knife point and disc systems.
• Good crop safety was observed with preemergence herbicides under knife-points; however, herbicide damage was evident under discs and was due to shallow seeding depth.

• Foliar zinc decreased grain cadmium concentration at only one of three sites, when zinc was applied twice.
• The timing of zinc application had no significant effect on wheat grain cadmium concentration.
• Soil applied zinc had no effect on wheat grain cadmium concentration.
• The recommended rate of foliar zinc (0.33 kg Zn/ha) may not be sufficient to decrease cadmium uptake.

• There was no significant interaction between sowing time and phosphorus (P) in response in 2014 and 2015.
• Both sites and years responded positively to P fertiliser with 10kg P/ha achieving a relative yield of 88% and 97% in 2014 and 2015 respectively.
• Further research is required to determine if winter canola requires less applied P than slow spring phenology types (due to teh longer vegetative phase to accumulate biomass by flowering. 

• Increased nitrogen application rates equated to increased grain yield.
• Eary sowing had a grain yield advantage of 0.74t/ha averaged accross all varieties and nitrogen application rates.
• Corack was the highest yielding variety in this trial.
• Splittimg nitrogen application in the second time of sowing increased grain yield. 
• Grain protein concentration increased as nitrogen application rates increased.
• The highest protiens occured at the maximum nitrogen rate of 160kg/ha in Lancer, EGA_Gregory and SPitfire from the 12th May sowing. 

• In 2019, the highest yields came from sowing in late March due to the dry spring conditions and only mild frosts at Wallendbeen.
• Nuseed Diamond was the highest yielding variety from all sowing dates. The highest yield was from the late March  sowing date.
• The winter varieties were lower yielding than the spring types, with yields declining from later sowing dates.
• Open pollinated triazine tolerant varieties were generally lower yielding than the hybrid Clearfield® varieties with similar phenology.

• Grain yeild was maximised by matching variety phenology with the correct sowing time to target the optimal flowring period.
• Early maturing spring types sown on 16 April suffered frost damage and reduced grain yeild as a result of higher moistuer and heat stress conditions at flowering. 
• The highest yielding variety was Sunvale (6.3t/ha) sown on 16 April.
• Beckon sown on 7 May yielded 6.2t/ha and Condo swn on 28 May yielded 4.9t/ha

• The variety Beckom sown on 5 May yielded highest (5.67 t/ha).
• Grain yield reductions up to 4t/ha occured when varieties were not sown at the correct time (due to flowering throughout August - September frost events).
• Greatest yield losses occured when quick maturing varieties were sown early rather than longer season varieties sown late.
• Winter wheats and very long springs spring wheats performed better in 2015 than 2014, presumably due to less aphid pressure (BYDV) in 2015. 
• Grain yield was maximised when winter wheats were sown early (mid-April) or mid to mid-fast varieties were sown in teh first week of May. If spring conditions had been favourable, the winter whaets may have outperformed the mid to mid-fast varities when sown in late May.
• Screening increased as sowing was delayed. 

• The highest grain yields were attained from mid May sowing accross all barley varieties.
• Longer-season varieties were high yielding in the 2016.
• Oxford acheived the highest grain yield for both sowing dates.
• Lodging was prevalent in 2016, significantly reducing grain yield oil susceptible varieties in the first sowing.

• For all varieties, the middle sowing date (4 December) resulted in higher grain yields than the early (11 November) or late (23 December) sowing dates.
• Varieties, N005A-80 and BidgeeA consistently achieved the highest seed protein concentrations.
• Varieties, SnowyA and BidgeeA achieved consistent seed protein concentrations across the three sowing dates, while later sowing dates reduced the seed protein of Djakal, N005A-80 and P176-2 varieties.

• The later sown canola resulted in greatly reduced yields and lower oil contents.
• Aphid pressure was moderate from flowering to podding but no spray was applied.

• Cooler spring temperatures and excellent plant available soil moisture, favoured the yield potential of longer season and mid maturing wheat varieties in 2016.
• The mid–late and mid-season bread wheat varieties SuntimeA, LRPB FlankerA, SuntopA, BeckomA, MitchA and EGA GregoryA all performed well from an April 27 sowing date (SD1) with yields >6.5 t/ha. The new long-season spring type SunmaxA, likewise achieved ~6.5 t/ha.
• The longer season bread wheat varieties LRPB KittyhawkA and SunlambA also demonstrated their yield potential, achieving yields >6 t/ha for SD1.
• Varieties that performed well across the three sowing dates included EGA GregoryA, MitchA, LRPB FlankerA, SuntopA and BeckomA.
• The new mid-fast season variety LRPB ReliantA yielded well from a main season and delayed sowing date.
• Warm autumn temperatures resulted in many spring wheat entries, particularly the more temperature responsive cultivars, reaching anthesis faster (days from effective SD to anthesis) for SD1 compared with SD2. LRPB LancerA for example was ~9 days faster to reach anthesis for SD1 vs SD2.
• The advanced durum line AGT D043 performed well, achieving yields comparable to the best performing durum DBA AuroraA and bread wheats from a main season sowing date.

• Grain yield was highest from the early sowing date (17 April) .
• Pioneer 44Y89 (CL) was the higest yielding variety.
• The early sowing treatments grew more total biomass and had a higher harvest index than the two later sowing dates.
• Pioneer 44Y89 (CL) had a better harvest index than all other varities in this experiment.

• It is critical to match sowing time with yield varietal phenology to optimise yield potential
• Longer-season varieties were high yielding in 2016 due to the extended grain filling period due to adequate soil moisture and mild spring temperatures
• There is a range of newer varieties with varied phenology with high yield potential 

• Sowing canola early highlights the inherent differences in phenology.

• Slow-developing varieties maintained consistent yield across all sowing dates (late March to late April), whereas fast-developing varieties achieved their highest yield from late April sowing.

• Early flowering (from sowing fast-developing varieties early) reduced yield potential and exposed those treatments to greater disease pressure.

• Early sowing exacerbated phenological differences between the varieties.
• The spread of days to reach 50% flowering within each time of sowing (TOS) varied by 35, 26 and 14 days in TOS 1, TOS 2 and TOS 3 respectively.
• The highest yield was acheived by Nuseed GT-50 (3.9 t/ha) sown on 1 May.
• Hyola 600RR was the highest yielding variety when averaged across all sowing dates.
• The sowing time had a neglible impact on grain yield. 
• The biomass at 50% flowering was greatest in TOS 2 (9.92 t/ha) followed by TOS 1 (7.93 t/ha) and TOS 3 (9.23 t/ha).
• There was strong correlation between biomass at maturity and grain yield, i.e. a higher biomass produced a higher yield.  

• Frost and terminal drought were key determining factors on barley grain yield and development at Condobolin in 2017.
• Selecting sowing date and varietal phenology maximised grain yield by timing flowering for the first week of September at Condobolin.
• Grain plumpness, as indicated by screenings and retention, can be adversely affected by late sowing dates in the absence of spring rainfall.

• Slower maturing varieties had the highest yields in 2016, uncharacteristic of long-term yield trends in central west NSW, where weather conditions typically favour shorter-season varieties.
• While anthesis date is a important contributor to yield, high rainfall and a long grain filling period diluted this association and was confounded by lodging, secondary tillering and waterlogging events.
• Highest yields were attained from the second sowing date (mid May), while late sowing dates suffered yield penalties due to poor plant establishment from waterlogging.  

Key findings

 Sowing time had a huge effect on grain yield.

 Delaying sowing time reduced grain yield, TOS 1 yielded 4.84 t/ha and TOS 2 yielded 3.55 t/ha.

 Suntop was the highest yielding variety, 4.47 t/ha.

 Lancer was the lowest yielding variety, 3.73 t/ha.

 Given profitability and return on investment 40 kg N/ha at sowing was the ideal rate of nitrogenSowing time had a huge effect on grain yield.

Delaying sowing time reduced grain yield in all varieties across all nitrogen treatments.The effect of nitrogen varied between the two sowing times. The ideal target rate of nitrogen, given profitability and return on investment was 40 kg N/ha.

Key findings:

• Sowing time had a huge effect on yield.
• Delaying sowing time reduced grain yield in all varieties across all nitrogen treatments. 
• Given profitability and return on investment 40 kg N/ha at sowing was the ideal rate of nitrogen.

• The combination of extra stored water (20mm) and early sowing (17 April) resulted in the highest grain yield in this experiment.
• Early sowing without extra stored water gave a higher yield than late sowing (4 May), regardless of teh irrigation treatment at the later sowing date.
• The extra grain yield from early sowing and irrigation was due to increased biomass accumulation and imprved harvest index.
• Oil concentration was low overall, but was higher from the early sowing (33.6%) than th elater sowing (30.5%).

• LBP10 - 0018 was the highest yielding variety sown on the 30th April (2.09 t/ha)
• Emu Rock was the highest yeilding variety sown on 22 May (1.72 t/ha) and 11 June (0.89 t/ha)
• Emu rock was the highest yielding variety (1.49 t/ha) when averaged accross all sowing times.
• Dry conditions during September and October contributed to the lower average yields in the 22 May  and 11 June sowing times

A field trial was undertaken at Watchman in 2020 to investigate combinations of barley sowing time, seed rate and herbicide treatments to control brome grass. The average seedbank of brome grass at the site was 2140 ± 178 seeds/m2. Delaying sowing by three weeks did not impact on barley establishment (P=0.368) and brome grass plant density (P=0.417). However, delayed sowing of barley did have a significant effect on brome panicle density (P=0.019) and it had an interaction with herbicide treatment on brome seed production (P=0.049). This lack of an effect of delayed sowing on brome plant density, compared to other brome sites indicates presence of high seed dormancy in Watchman population. Barley seed rate did not have a significant effect on brome panicle production (P=0.854), or brome seed production (P=0.392). However it did have a small, but significant impact on barley yield with a 6% increase in grain yield when barley seed rate was increased from 100 to 200 seeds/m2 (P=0.049). Increase in barley seed rate also significantly reduced barley grain contamination with brome grass seeds by 38% (P=0.049). Herbicide treatments had a significant effect on brome plant density (P<0.001), brome panicle density (P<0.001), brome seed production (P<0.001), brome grain contamination (P<0.001), and barley grain yield (P=0.023). Where IMI herbicide treatments were applied in this trial, brome grass control was improved greatly, which resulted in an increase in barley grain yield. These IMI herbicides were effective in providing high levels of brome grass control and should be considered a very useful tool in the management of brome grass. While herbicide resistance to these herbicides is common in annual ryegrass, IMI resistance in brome grass is far less common. However, over reliance on IMI herbicides should be avoided in order to preserve their activity for the future.

Canola establishment was significantly influenced by the variety (P=0.012) and seed rate (P<0.001). Greater plant density in the hybrid variety T4510 (36 plants/m2) than the open pollinated Bonito (31 plants/m2) is likely to be associated with the larger seed size and greater early vigour in the hybrid. Plant density achieved was within 10% of the target density. There was a significant interaction between sowing time of canola and herbicide treatments (P=0.004). This interaction was mainly associated with a significantly lower brome grass density in the control (glyphosate). In contrast, brome grass density was very similar between the two sowing dates where pre-emergent and post-emergent herbicides were used. Consistent with the trend of brome grass panicle density, brome grass seed production in this trial was significantly influenced by the herbicide treatment (P<0.001). The results also show that brome grass panicles set more seeds when only the knockdown or Atrazine IBS was used (49-59 seeds/panicle) as compared to post-emergence Haloxyfop treatments (30 seeds/panicle). Canola grain yield was significantly affected by the time of sowing (P=0.034), with the earlier sown crop (1.58 t/ha) producing higher yield than the later sowing (1.35 t/ha). The hybrid variety Invigor T4510 (1.56 t/ha) produced significantly higher grain yield than the open-pollinated Bonito (1.37 t/ha) (P<0.001). Increase in canola plant density from 25 to 50 plants/m2 also caused a significant increase in grain yield (P=0.002), even though the yield improvement was only 100 kg/ha. Even though brome grass density at the site was fairly low (~12 plants/m2), herbicide treatments had a significant positive effect on canola grain yield (P<0.001). Controlling brome increased income by $169/ha or 21% after including the cost of the herbicides and applying the herbicides when averaged across the trial.

A field trial was undertaken at Mallala in 2019 to investigate combinations of wheat sowing time, seed rate and herbicide treatments to control brome grass. The average seedbank of brome grass at this site was 2877 ± 406 seeds/m2. The two week delay in sowing reduced average in-crop brome density from 567 plants/m2 to 352 plants/m2 (38%). Even though the reduction in brome density at Mallala was significant, it was a much lower reduction than that observed in the trial at Riverton (82% reduction). This difference in brome grass density with delayed sowing at these two sites highlights the large differences in seed dormancy between the populations of this weed species. Brome grass panicle density was significantly affected by wheat seed rate (P=0.039), and herbicide treatment (P<0.001) but not by the time of sowing (P=0.152). Increasing seed rate of wheat suppressed brome grass growth and reduced its panicle density. As wheat density increased from 100 seeds/m2 (low) to the highest seed rate (200 seeds/m2 – high) brome panicle density was reduced by 39%. These results support previous findings that higher crop density can be an important part of an integrated weed management program. Wheat grain yield increased consistently with the increase in seed rate or crop density. This trend correlates well with the improved suppression of brome grass panicle density observed in the trial. Not only did higher wheat density achieve superior weed suppression, it also provided a significant increase in grain yield. Herbicide treatments also had a highly significant effect on brome grass panicle density. However, there was no interaction herbicides and TOS or seed rate. This indicates that herbicides performed similarly in both times of sowing and the three seed rates. Sakura + Avadex significantly reduced panicle density as compared to Treflan + Avadex and Intercept (Clearfield technology) was used after pre-emergent Treflan + Avadex, it prevented brome plants from producing panicles (3 panicles/m2). Herbicide treatments had a large and significant effect on grain yield of wheat at Mallala (Figure 5). This is not surprising considering the high weed density present at the site and high competitive ability of brome grass. The treatment of Treflan + Avadex produced only 1.11 t/ha, which was significantly lower than the more expensive pre-emergent herbicide mixture of Sakura + Avadex (1.81 t/ha). However, when Intercept post-emergence herbicide was used, wheat yield increased further to 2.63 t/ha. In this trial, integration of Clearfield technology with pre-emergent herbicides not only prevented brome grass seed set as shown but the panicle density, it also delivered the highest grain yields.

A field trial was undertaken at Riverton in 2019 to investigate combinations of wheat sowing time, seed rate and herbicide treatments to control brome grass. The average seedbank of brome grass at the site was 1863 ± 303 seeds/m2. Brome grass at this site was effectively controlled (>80%) by delaying sowing by 2 weeks, with treatment effects from herbicide and wheat seed rate treatment only being significant in the early sown plots, where brome grass density was high. These results clearly indicate that brome grass population present at this site has very low seed dormancy and germinates readily after the season opening rains and can be effectively controlled with a knockdown herbicide. Wheat grain yield results reflected the level of brome grass control with herbicide and wheat seed rate treatments improving yields significantly as brome suppression improved. These treatments did not have a significant effect on yield when sowing was delayed because brome was effectively controlled by the knockdown herbicides. In the early sown crop when brome grass was controlled effectively with Intercept®, the 2 week delay in sowing caused a 9% reduction in wheat yield.

• There were large weed control benefits of delayed sowing of barley at Minnipa. However, when a highly effective pre-emergent herbicide was applied the benefit of delayed sowing was negligible.
• In barley a three week delay in sowing time did not significantly reduce grain yield as it did in the previous year in wheat. Lower yield penalty in barley from delayed sowing may be related to its earlier maturity and more competitive nature compared to wheat.

 

A field trial was undertaken at Minnipa in 2019 to investigate combinations of barley sowing time, seed rate and herbicide treatments to control annual ryegrass. The average seedbank of annual ryegrass (ARG) at the site was 4168 ± 411 seeds/m2. ARG plant density was significantly influenced by the time of sowing (P<0.001), herbicide treatment (P<0.001) and the interaction between the time of sowing and herbicide (P<0.001). There was a large impact of the 3 week delay in seeding barley on ARG plant density. This was particularly evident in the untreated control in which ARG density decreased from 676 plants/m2 in TOS 1 to 379 plants/m2 in TOS 2. This large reduction in ARG density due to delayed sowing is most likely related to rainfall events in early May, which would have caused weed emergence. Pre-emergence herbicides had higher efficacy in TOS 2 where the density of ARG plants had been reduced by the delay in seeding. This trend held through the season in the untreated control in which ARG spike density decreased from 306 spikes/m2 in TOS 1 to 199 spikes/m2 in TOS 2. In the trifluralin treatment, ARG produced 5078 seeds/m2 in TOS 2 as compared to 9192 seeds/m2 in TOS 1, a 45% reduction in ARG seed production. Unlike wheat in 2018, barley grain yield at Minnipa was not significantly influenced by the time of sowing (P=0.644). However, seed rate (P<0.001), herbicide treatment (P<0.001) and had a significant effect on barley grain yield. As stated earlier, there were large benefits of delayed sowing on weed control. In barley a three week delay did not significantly reduce grain yield as it had in the previous year in wheat. Lower yield penalty in barley from delayed sowing may be related to its earlier maturity than wheat.

Barley grain yield as significantly influenced by the time of sowing (P=0.025), seed rate (P<0.001) and the herbicide treatment (P<0.001). The delay of 4 weeks between the two sowing dates caused 22% (0.69 t/ha) reduction in grain yield or 25 kg/ha/day. Averaged over the two sowing dates and three seed rates, Boxer Gold treatment (2.996 t/ha) produced significantly greater barley grain yield than Treflan (2.634 t/ha) and the control (2.648 t/ha). Barley sown early (TOS 1) at high seed rate and sprayed with Boxer Gold produced 3.6 t/ha grain yield as compared to later sown crop (TOS 2) at low seed rate but treated with the same herbicide which produced 2.4 t/ha.

A field trial was undertaken at Washpool in 2020 to investigate combinations of barley sowing time, seed rate and herbicide treatments to control annual ryegrass (ARG). The average seedbank of ARG at the site was 1949 ± 496 seeds/m2. Time of sowing significantly influenced ARG plant density, with lower ARG plant density when seeding was delayed (P<0.001). Herbicide treatment had a significant influence on ARG plant density (P<0.001) due to 58% reduction in ARG plant density by the tank-mix of Boxer Gold and Trifluralin compared to the untreated control (155 plants/m2). Herbicide treatments also reduced ARG spike density and seed production. The mixture of Boxer Gold and Trifluralin reduced ARG spike density and seed production compared to the untreated controls by 45% and 42% respectively. ARG seed set was significantly lower in TOS 1 (18,911 seeds/m2) than in TOS 2 (30,990 seeds/m2) (P<0.001). Even though there was a higher ARG plant density in TOS 1 than TOS 2, greater competitive ability of early sown barley was able to reduce ARG spike density and seed production. Barley grain yield at this site was significantly affected by the time of sowing (P=0.014) and herbicide treatments (P=0.009). The control of ARG by the mixture of Boxer Gold and Trifluralin was reflected in barley yield improvement. The results of this study clearly showed that delayed sowing of barley can reduce ARG plant density but reduced competitive ability of the later sown crop often allows greater seed set by ryegrass that is also associated with a yield penalty.

General application of Sakura + Avadex over the whole trial site provided good control of ARG. As a result, follow-up application of Boxer Gold @ 1.5 L/ha or 2 L/ha at GS 11 (1-leaf stage) did not significantly reduce ARG plant density.  Post-emergence application of Boxer Gold at 1.5 or 2 L/ha after pre-emergence Sakura + Avadex extended the period of weed control, which reduced spike density of ARG (P=0.02). At both sowing times, increase in wheat plant density from 100 to 200 plants/m2 reduced ARG spike density by 44%. Delayed sowing at this site reduced the competitive ability of wheat against ARG. Averaged across the seed rates and herbicide treatments, ARG produced 234 spikes/m2 in TOS 2 as compared to 75 spikes/m2 in TOS 1 (68% reduction in TOS 1). Additional post-emergence application of Boxer Gold significantly increased wheat grain yield (P=0.008) compared to the baseline treatment of Sakura + Avadex. Wheat yield increased by 9% or 0.4 t/ha with the additional post-emergence treatment of Boxer Gold as compared to Sakura + Avadex treatment alone. Wheat grain yield was also significantly affected by wheat seed rate (P<0.001). Wheat grain yield increased from 4.6 t/ha at the density of 100 plants/m2 to the maximum of 5.48 t/ha at the seed rate of 200 plants/m2. This yield gain of 0.9 t/ha clearly indicates that early sowing, wheat density of 200 plants/m2 and effective use of herbicides can have a large influence on the profitability of wheat in the HRZ.

Wheat grain yield at Minnipa was significantly influenced by the time of sowing (P=0.002), seed rate (P<0.001), herbicide treatment (P<0.001) and the interaction between the time of sowing and herbicide treatments (P<0.001). Averaged across the seed rates and herbicide treatments, wheat produced grain yield of 1.67 t/ha in TOS 1 as compared to 1.06 t/ha in TOS 2. There were large benefits of delayed sowing on weed control. However, these benefits came at a significant cost in wheat grain yield.

Annual ryegrass (ARG) spike density and seed production were significantly reduced when seeding was delayed by two weeks (P=0.015 and P=0.017). This was not expected as ARG plant density was not significantly different between TOS 1 and TOS 2. Greater seed production by ARG in TOS 1 than in TOS 2 appears to be associated with good rainfall in late spring, which was used effectively by ARG but the crop was approaching physiological maturity and could not make use of increased plant available water. Crop type had a significant influence on ARG seed production with 23 to 53% lower ARG seed production in other cereals than Scepter wheat. Both ARG spike density and ARG seed production were significantly influenced by the herbicide treatment (P=0.017 and P=0.052). The new herbicide Overwatch® provided 30% greater ARG control than Boxer Gold®. Crop type also had a significant influence on grain yield (P<0.001), with barley generally yielding higher than wheat. Herbicide treatment had a significant influence on grain yield (P<0.001), where a 30% greater ARG control by Overwatch® than Boxer Gold® resulted in a 14% improvement in grain yield.

The trial site at Mallala was infested with a large seedbank of group A resistant brome grass, which made weed control in canola very difficult. Furthermore, the trial site experienced drought like conditions for most of the growing season which reduced the efficacy of atrazine. Even though the two-week delay in sowing reduced brome grass density from 927 plants/m2 in TOS 1 to 704 plants/m2 in TOS 2 (25%), this difference was not statistically significant.  However, the herbicide treatments (P=0.005) and the interaction between sowing date and herbicides (P=0.006) had a significant effect on brome grass plant density. Herbicide performance at the site was negatively affected by dry conditions and group A resistance in brome grass. As a result, even the best treatment combinations had more than 300 panicles/m2, which could lead to a large seed set in brome grass. When averaged across the sowing time, seed rate and herbicides, HyTTec Trophy produced 38% higher grain yield than Bonito. This difference in variety performance is consistent with superior crop establishment in HyTTec Trophy than Bonito. As a result of herbicide resistance in brome grass, yield increase in the Verdict treatment compared to the control (atrazine POST) was non-significant. However, use of clethodim increased yield by 61% compared to the control, which was statistically significant.

Barley plant density was significantly influenced by the time of sowing (P=0.025) and crop seed rate (P=0.002).  Averaged across the seed rates and herbicide treatments, the first time of sowing (TOS 1) had barley density of 125 plants/m2 compared to 82 plants/m2 in TOS 2, which was related to dry soil conditions after sowing in TOS 2. Brome grass plant density was significantly affected by the time of sowing (P=0.018) and the herbicide treatments (P<0.001).  The 4-week delay in sowing between TOS 1 and TOS 2, allowed greater emergence of brome grass seedlings before the sowing of the TOS 2.  Consequently, barley sown at TOS 2 had 48% lower brome grass infestation (107.9 plants/m2) than in TOS 1 (207 plants/m2). As expected, herbicide treatments had a significant (P<0.001) effect on brome grass density. When averaged across the sowing time and seed rates, the treatment of Treflan + Avadex was only moderately effective and reduced brome grass density by 36% (173 plants/m2) relative to the untreated control (271 plants/m2). In contrast, the same pre-emergent treatment (Treflan + Avadex) followed by Intervix reduced brome grass density by 90% (28 plants/m2). When averaged across seed rates and herbicide treatments, the time of sowing barley had a significant effect on its grain yield (P=0.011). TOS 1 produced 940 kg/ha greater barley grain yield than TOS 2. The post-emergence application of Intervix to the crop treated with Treflan + Avadex further increased barley grain yield by 872 kg/ha. These results are consistent with the trends in brome grass density and panicle production. The untreated control plots produced 40% lower grain yield than the Intervix treatment, which completely controlled brome grass. These results highlight the strong competitive ability of brome grass in cereals.

The average seedbank of ARG at the site was 3932 ± 270 seeds/m2. ARG plant density was significantly influenced by the time of sowing (P<0.001), herbicide treatment (P<0.001) and the interaction between the time of sowing and herbicide (P<0.001). The delay in seeding from TOS 1 to TOS 2 (16 weeks) caused a large reduction in ARG plant density. This was particularly evident in the untreated control in which ARG density decreased from 825 plants/m2 in TOS 1 to 31 plants/m2 in TOS 2 (96% reduction). This large reduction in ARG density due to delayed sowing is most likely related to an effective knockdown herbicide treatment after most ARG had emerged before TOS 2. Herbicide treatments reduced ARG plant density significantly in TOS 1, however herbicide effect on ARG plant density in TOS 2 was non-significant, possibly due to a much lower ARG density. While the delay in sowing significantly reduced ARG plant density (P<0.001), it did not significantly reduce ARG seed spikes (P=0.495). This result indicates that despite low ARG plant numbers in TOS 2, faba beans failed to compete effectively with ARG and suppress its growth. As a result, even at a relatively low density ARG was able to produce a large amount of seed for future infestations. Faba bean grain yield at Frances was significantly influenced by the time of sowing (P=0.033), seed rate (P<0.003), and herbicide treatment (P<0.001). Averaged across the seed rates and herbicide treatments, faba beans produced grain yield of 1.34 t/ha in TOS 1 as compared to 1.81 t/ha in TOS 2. Superior faba bean grain yield in TOS 2 In 2018 at Frances is most likely due to the reduction in ARG plant density.

• Stubble height would appear to have a statistically significant effect on early lupin plant height.
• This effect, although trending towards a higher lower pod height on those plants, is not statistically significant in this trial.
• This trial had insufficient measurements taken to determine the mechanism that caused the plants growing in the tall residue to grow taller and have a higher first pod, and whether that led to an increase in yield.