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.

• Short season variety, Condo yielded the highest (5.75 t/ha).
• There was no significant difference between applying 40 + 40 kg N/ha (5.77 t/ha) split application and the single 80 kg N/ha (5.75 t/ha).

• The 12 barley varieties were, on average 26%, higher yielding than the 4 wheat varieties in this experiment.
• the fast developing wheat varieties Emu Rock and Condo generally reached anthesis around the same date as the slow developing barley varieties Navigator, Oxford and Urambie.
• Long season barley varieties such as Oxford and Urambie performed well for early sowing (24 April) but most barley lines had their highest yield from main season sowing (12 May).
• The four early season wheat varieties generally had better yield from main season sowing than from early sowing. 

• Winter cereal varieties differ in their levels of yield loss and responsiveness to crown rot and growers can use these rankings to improve production in the presence of this disease.
• Grain yield and responsiveness to crown rot appear strongly correlated in these experiments.
• Grain yield losses vary between seasons with up to a 25% reduction measured in southern NSW.

• Three seasons of research have provided confidence that V071 is a superior rice variety to Reiziq in all agronomic attributes.
• The V071 grain yield was higher than Reiziq in all experiments by an average of 1.43 t/ha.
• V071 development does not slow during periods of low temperatures like Reiziq, which is very beneficial in cool seasons.
• V071 has strong emergence and establishment vigour like Reiziq, and a higher tolerance to grain shattering than Reiziq.
• Provided V071 meets market quality requirements, it is showing potential to be a welcome replacement for Reiziq, the current industry standard bold medium-grain rice variety for the past 18 years.

• The critical pHCa threshold is in the range of 5.2 to 5.4, below which faba bean growth is reduced.

• Variability for tolerance to low pH is present within the species with cultivar (cv) PBA ZahraA more tolerant at low pH than cultivars (cvv) PBA SamiraA, FarahA or PBA NasmaA.

• The sensitivity of uninoculated faba bean plants to low pH suggests it may not be sufficient to overcome the poor performance of faba bean on acid soils simply by developing more acid-tolerant rhizobium. Further research is warranted to address this question.

• Genotypic variability observed in response to wheat grain yield in alkaline sodic subsoil.
• MaceA, CorackA, ScepterA and Emu RockA were the top performing cultivars over three consecutive years.
• Higher grain yield was attributed to greater subsoil water extraction and capacity to maintain higher harvest index under drought conditions.

• 60 thrips per plant four weeks after cotton emergence.
• Cruiser® seed treatment reduced thrips larvae numbers at one week after cotton emergence.
• Thimet® in-furrow treatment reduced thrips larvae numbers at one and three weeks after cotton emergence. » Hand-harvest yields indicated the Thimet® treatment increased yields over no Thimet®-treated plots.
• Machine harvest yields were not significantly different between treatments.

• Seasonal conditions and soil type have a greater effect on carbon than management.
• Providing necessary nutrients and pH for optimum pasture production will potentially increase soil carbon.
• Cropping in a good season might not decrease soil carbon stocks. Opportunities could exist for Monaro landholders to diversify their enterprises when the conditions are right without depleting their soil carbon.
• A rapid increase of soil carbon can easily be followed by a rapid decrease.
• For more information please see our eBook: Soil carbon in the Monaro region (https://itunes.apple.com/au/book/ id1035198100 or http://tinyurl.com/zrr9mht).

• N2O emissions at the Gunnedah site were approximately 10 times higher than at the Emerald site, due to the wet soil conditions and high pre-season rainfall at Gunnedah which led to denitrification of N from pre-season anhydrous ammonia application.
• Two nitrification inhibitors, DMPS (“Big N-sure”, Incitec Pivot Fertilisers) and nitrapyrin (“N-serve”, Dow AgroSciences) directly injected into anhydrous ammonia during pre-plant N application delayed the conversion of applied ammonium in the soil to nitrate for a period of 2–3 months.
• At the Gunnedah site, cumulative N2O emitted was reduced by 86% (DMPS) and 65% (nitrapyrin), compared to untreated ammonia.

Conclusions: 

In a season such as that experienced at the Emerald 2016–17 site, there were only minor environmental benefits from using a nitrification inhibitor in conjunction with anhydrous ammonia. However, these experimental conditions may not be typical as pre-plant fertiliser is usually applied earlier in the year at Emerald than it was at this site. A longer period of time between pre-plant application and plant establishment would provide greater opportunity for N2 O losses to occur, although the potential for heavy winter rainfall tends to be low in the Emerald region. While both inhibitor products clearly reduced emissions during the first two measurement periods, it was apparent that the effectiveness of these products had dissipated by the time of the second irrigation. The additional inhibitor application with the side-dressed urea boosted the N2 O reduction period for the DMPP treatment, while the application of untreated urea to the other treatments allowed further losses matching those of the untreated control after the initial pre-plant N application. The 2016–17 Gunnedah experiment provided the perfect testing conditions for nitrification inhibitors as the soil was very wet at application, and received frequent heavy rainfall during the next 3 months. These inhibitors were designed to retain mineral N from applied N fertiliser in the soil during periods of excessive rainfall that may otherwise lead to large losses of nitrate N through denitrification and leaching. Leaching occurs through downward movement of nitrate with water in the soil, but we found no evidence of this having occurred in the soil core samples we took just prior to sowing. For heavy clay soils such as this one at Gunnedah, denitrification of soil nitrate during periods of anaerobic soil conditions is the most likely major N loss pathway. The results of the gas sampling campaigns highlighted the almost complete mitigation of N2 O emissions during this period by adding nitrification inhibitors. The Big N-sure® inhibitor appeared to remain active for longer in the soil than the N-serve®.

• Soil water can be predicted from EM38 measurements made on the soil surface in southern dryland cropping soils.

• It is possible to estimate the amount of water and its distribution in the top 50 cm of soil.

• Rapid surveys of large areas and/or high numbers of experiment plots will be possible.
 

• Neither varying row configuration or hybrid affected yield at this site, given average site yields of 2.14 t/ha.
• Slightly higher yields were obtained from the 30,000 plants/ha and 50,000 plants/ha target plant populations.
• Thousand grain weight increased as row spacing widened, and decreased as plant population increased.
• Screenings were low across all treatments.
   

• Neither varying row configuration or hybrid affected yield at this site, given average site yields of 2.14 t/ha.
• Slightly higher yields were obtained from the 30,000 plants/ha and 50,000 plants/ha target plant populations.
• Thousand grain weight increased as row spacing widened, and decreased as plant population increased.
• Screenings were low across all treatments.
   

• In a low-yielding season varying row configuration had no effect on sorghum yield.
• Yield declined as plant population and hybrid tillering ability increased and staygreen levels decreased.

• Row direction was the only factor that affected final grain yield at this site in this season.
• Sorghum sown in a north–south direction yielded 7% more than sowing east–west.
   

• Varying row direction (north–south vs east– west) had no effect in this trial in this season.
• Row configuration did influence final grain yield with the solid plant out yielding the superwide and single skip treatments by 0.93–1.29 t/ha respectively.

Key message:

• Varying row direction from north–south or east–west did not affect grain yield or quality.
• Row configuration did not affect grain yield, however, there were some effects on grain quality. The solid row configuration produced higher grain protein and screenings levels, but lower test weight than the superwide and single skip treatments.
• There were differences between the hybrids for grain yield and quality. MR Apollo and MR 43 produced higher yields than 84G22. Differences in grain quality were also found, with MR Apollo producing a higher grain protein level and 1000-grain weight than the other two hybrids.

Conclusions:

The effect from row direction on plant structures was minor, with only an increase in plant establishment detected from the north–south direction compared with the east–west direction. This difference did not translate into higher tiller or head production per hectare. There were slightly more tillers per plant and heads per plant from the east–west direction, but again this did not correlate with higher yields. Row configuration did not affect plant establishment or tillering, however, there were more heads produced per hectare from the solid configuration compared with the single skip. This did not translate into a difference in grain yield; however, there were some impacts on grain quality. The solid row configuration produced higher grain protein and screenings levels, but lower test weights than the superwide and single skip treatments. There were differences between the hybrids for grain yield, with MR Apollo and MR 43 producing higher yields than 84G22. There were also differences in grain quality, with MR Apollo producing a higher grain protein level and 1000-grain weight than the other two hybrids The results from this experiment suggest that there is no economic value in altering the sowing direction of rows to either north–south or east–west, or any yield benefit from altering row configuration between solid, single skip or superwide.

• Onion thrips were the dominant thrips species observed during monitoring.
• Western flower thrips constituted less than 5% of thrips monitored.
• During early cotton establishment there were more tomato thrips larvae than onion thrips larvae. By December, onion thrips larval numbers exceeded tomato thrips larval numbers.

• The frequency of winter cereals in the rotation have a large impact on crown rot inoculum build up.
• Monitoring paddocks over time is a powerful way to help crown rot management and the PreDictaB™ soil tests are an effective method for achieving this.
• The dominant wheat–canola rotation in southern NSW is increasing the region’s level of risk to losses caused by crown rot.
• Not all paddocks behave the same way and factors other than crop type are affecting crown rot behaviour.

• 55% of paddocks tested in 2014 and 80% of paddocks in 2015 had crown rot.
• 90% of paddocks tested in 2014 and 2015 had take all.
• The previous crop grown in the paddock can greatly influence the pre-sowing levels of crown rot and take all in the following year, particularly in a cereal on cereal rotation.
• Most paddocks with pre-sowing levels of crown rot and take all had increased inoculum levels throughout the growing season.
• Crop rotation and duration, and stubble management can reduce crown rot and take all infection risk.

• In a season characterised by low frost severity, Nuseed Diamond was the highest yielding variety for all three sowing dates.
• In a low frost severity season, earlier sowing on 27 March and 11 April achieved a higher grain yield compared with the later sowing on 30 April.
• Triazine tolerant varieties were generally lower yielding compared with other varieties with a similar phenology.
• Winter type canola yield and oil performance were comparable with spring types when sown before mid April and could be worth considering as a dual-purpose crop due to the additional value generated from grazing.

• Seasonal conditions, characterised by low frost incidence combined with heat stress and terminal drought conditions, significantly affected grain yield and quality responses.
• The highest yields were associated with earlier flowering; there was a significant yield penalty associated with later flowering of slower developing genotypes or when sowing was delayed.

• Seasonal conditions significantly affected phenology and yield responses to sowing date among barley varieties in 2019.
• Phenology significantly influenced yield and quality responses, whereby later flowering incurred severe yield and quality penalties, affecting overall profitability.

• Fertiliser nitrogen (N) rates should be tailored to suit paddock history and soil mineral N levels at sowing.
• Sorghum yields without N fertiliser, although high in a favourable season, were still well below those achieved using additional N fertiliser.
• At Tamworth, in-season rainfall ideally suited a split-N application strategy resulting in the highest yields.
• At Breeza, drier conditions meant that neither split N application nor slowrelease N products boosted grain yields above those reached using urea all applied at sowing.
• Gross margins for most alternative N strategies were greater than that achieved when no N was applied.
   

• Fertiliser nitrogen (N) rates tailored to suit paddock history/ soil mineral N levels optimised N2O emissions.
• At Tamworth, withholding N fertiliser on a high mineral N soil reduced N2O emissions, but did not optimise grain yield.
• At Breeza, most strategies of urea + nitrification inhibitor, polymer-coated urea and split N application substantially reduced N2O emissions. Most alternatives produced similar grain yields to the current practice of urea all applied at sowing, so the N2O emissions intensity per tonne of grain produced was also reduced.
• A 1:3 blend of urea + polymer-coated urea all applied at sowing, increased N2O emissions compared with the urea all at sowing treatment. The treatment also reduced grain yield, so potential slow-release treatments need to be carefully evaluated from both an N2O emissions and grain production point of view.

• Fertiliser nitrogen (N) rates tailored to suit paddock history/ soil mineral N levels optimised N2O emissions.
• At Tamworth, withholding N fertiliser on a high mineral N soil reduced N2O emissions, but did not optimise grain yield.
• At Breeza, most strategies of urea + nitrification inhibitor, polymer-coated urea and split N application substantially reduced N2O emissions. Most alternatives produced similar grain yields to the current practice of urea all applied at sowing, so the N2O emissions intensity per tonne of grain produced was also reduced.
• A 1:3 blend of urea + polymer-coated urea all applied at sowing, increased N2O emissions compared with the urea all at sowing treatment. The treatment also reduced grain yield, so potential slow-release treatments need to be carefully evaluated from both an N2O emissions and grain production point of view.

• Fertiliser nitrogen (N) rates tailored to suit paddock history/ soil mineral N levels optimised N2O emissions.
• At Tamworth, withholding N fertiliser on a high mineral N soil reduced N2O emissions, but did not optimise grain yield.
• At Breeza, most strategies of urea + nitrification inhibitor, polymer-coated urea and split N application substantially reduced N2O emissions. Most alternatives produced similar grain yields to the current practice of urea all applied at sowing, so the N2O emissions intensity per tonne of grain produced was also reduced.
• A 1:3 blend of urea + polymer-coated urea all applied at sowing, increased N2O emissions compared with the urea all at sowing treatment. The treatment also reduced grain yield, so potential slow-release treatments need to be carefully evaluated from both an N2O emissions and grain production point of view.

• Very dry conditions during the 2013−14 summer meant that much of the nitrogen (N) fertiliser applied was not taken up by the sorghum crop, especially if it had been applied in-crop at booting. Between 46–65% of the applied N remained in the soil at harvest in 2013−14.
• A following crop of unfertilised sorghum accessed the remaining N for crop growth and, at rates of 100 kg N/ha and above in the 2013−14 crop, increased grain yield and protein above the control. Late N application by topdressing in the 2013−14 crop gave similar crop production results to treatments where N was sidebanded at sowing.
• Two-year gross margins showed a significant benefit from N application as urea either at sowing or incrop.
   

• For three seasons, we applied isotope-labelled urea (15N) to sorghum in small (0.75–1.0 m2) plots, then calculated nitrogen (N) recovery by comparing the amount applied with the total 15N found in grain, crop residues and soil.
• Between 55–85% of the N fertiliser applied was recovered at harvest, meaning a 15–45% loss, presumably during wet soil conditions when nitrate denitrification led to N2 and N2O gaseous losses.
• In very wet conditions, little of the applied N remained in the soil at harvest, while in a dry season there was more of the applied N found in the soil at harvest than in the plant.

• After stem elongation, mature prickly lettuce plants are difficult to control.
• Controlling mature prickly lettuce plants early achieves better results.
• No single treatments, except paraquat, achieved 100% control of mature prickly lettuce plants that emerged after a wheat crop was harvested. The paraquat, either used alone or as a follow-up application, was the only outstanding treatment, achieving 100% control.
   

• Sunflower yields were very low at this site in 2015–16, averaging 0.56 t/ha.
• Plant population affected plant measurements, with larger head diameters and 1000 grain weights resulting from lower populations.
• Hybrid selection also affected plant measurements. Ausistripe 14 had the longest arc length but the smallest head diameter. Ausigold 4 and Ausigold 62 had very similar plant characteristics.

• The more area of leaf removed, the greater the yield loss in sunflowers.
• The greatest effect on yield was from total leaf defoliation at the start of flowering or the end of flowering, which reduced yield by 1.16 t/ha (78%) and 1.02 t/ha (66%) compared to the control.
• Removing the top 10 leaves at the end of flowering had no effect on grain yield or any of the quality parameters measured.

• Yields from the 35,000 plants/ha and 45,000 plants/ha target plant populations were significantly higher than the 25,000 plants/ha treatment (by 0.52–0.56 t/ha). Plant population did not affect oil content.
• The solid 75 cm treatment achieved a yield significantly higher than the solid 100 cm and superwide (150 cm) configurations. Varying row configuration did not affect oil content.
• Ausigold 62 and Hyoleic 41 produced higher yields than the experimental sunflower hybrid. Ausigold 62 had significantly higher oil content than the other two hybrids evaluated.

• Chickpea pods can split open when harvest is delayed (harvest date (HD)3 and HD4), allowing easy access for water and an easier exit for seeds that can drop to the ground before or during the harvest process.
• HD3 averaged 28.6% split pods per plant (varietal range of 2.8–51.9%) while HD4 averaged 46.0% split pods per plant (varietal range of 30.0–64.9%).
• Averaging across HD3 and HD4 for the desi chickpeas, Howzat had the least split pods (10.5%) and PBA SeamerA had the most (55.6%). For the kabuli chickpeas, Genesis™ 090 had the least split pods (22.5%) and Genesis™ KalkeeA was the worst affected (55.6%).
• Loss of seed from split pods and pod abscission, seed shattering and reductions in grain weight caused from delaying harvest were shown to reduce grain yields by up to 44%.
• A delay of six days with one rain event (44.2 mm) was enough to reduce the grain yield in chickpeas (averaged across varieties) by 2%, due to lower seed density.
• Growers should aim to harvest chickpeas on time to avoid yield losses and grain quality penalties at receival.
   

• The 2013 Tamworth and 2014 Trangie environments were not conducive to high levels of seed markings, with all varieties having <5% tiger stripe/blotches.
• The later sown chickpeas had a lower incidence of seed markings in two of the three environments.
• The 2015 Tamworth experiment was conducive to seed markings for the first sowing date (SD1). In this case, the most susceptible commercial varieties were PBA PistolA and PBA BoundaryA, with 9.7% and 6.7% of individual seeds having tiger stripe/blotches respectively.
• All five kabuli varieties did not display any seed markings in any of the three environments.
• All desi varieties showed at least low levels of tiger stripe/blotch type markings in one or more of the three environments and two sowing dates

Conclusions

Time of sowing and variety influence the amount of seeds showing the tiger stripe/blotching type markings in chickpea. Kabuli chickpeas do not suffer from this defect. Desi chickpeas sown in mid-June at Tamworth and Trangie had a lower incidence of this type of seed marking. Research is ongoing to identify both the genetic basis and the environmental triggers of tiger stripe/blotch type markings in desi chickpeas to minimise any potential risk to the Australian chickpea industry.

• Applying a monolayer of ethylene glycol monooctadecyl ether polymer reduced evaporation by 50%–60% under small scale, controlled environmental conditions.
• Under field situations its efficacy is significantly reduced and produces inconsistent results with evaporation savings of less than 10%.
• Windy conditions and/or a decrease in the polymer’s longevity on the water surface under field situations probably cause this reduced effectiveness.
   

• In the unusually wet growing season of 2016, increasing the barley plant density did not increase the yield of all varieties.

• High tiller numbers reduced overall grain size.

• In ideal growing conditions, some varieties with lower plant densities of <125 plants/m2 out-yielded higher density treatments.

• Ancient barley germplasm from Ethiopia harbours resistance to scald and other diseases.
• Twenty-eight out of 355 Ethiopian lines were moderately resistant to scald.
• Careful selection for disease-resistant lines is important to retain other desirable traits.

• Nuseed Diamond achieved 5 t/ha grain yield from early sowing (watered for germination on 12 April).
• The high yield of Nuseed Diamond was due to its high biomass accumulation and high harvest index. ATR BonitoA was the lowest yielding variety, largely because it accumulated less biomass than hybrid non-TT varieties.
• Split nitrogen application resulted in higher grain yield than all nitrogen applied at sowing or all nitrogen
delayed to the 8-leaf stage.

• Pioneer® 45Y88 (CL) was the highest yielding variety, averaging over 4 t/ha, with Nuseed Diamond and Pioneer® 45Y25 (RR) also achieving high yields.
• Sowing on 5 April resulted in higher grain yield, reduced lodging and lower oil content compared with sowing on 26 April.
• A plant population of 35–56 plants/m2 resulted in higher grain yields than populations of 18 plants/m2 or 68 plants/m2.
• Applying 200 kg N/ha resulted in higher grain yields than 150 kg N/ha when the soil available nitrogen (N) at sowing was 64 kg/ha. Nitrogen rates above 200 kg N/ha resulted in no extra yield.
• Increasing N application rates above 200 kg N/ha reduced oil concentration.
• Crop lodging increased with plant populations above 35 plants/m2 and N rates above 150 kg N/ha.

• Correct varietal selection and optimal agronomic management can result in irrigated wheat yields of over 10 t/ha.
• LongReach CobraA, LongReach TrojanA and BeckomA were the highest yielding varieties.
• Delaying nitrogen fertiliser application by applying the greatest amount at booting was shown to improve grain protein concentration and reduce lodging compared with applying more nitrogen at sowing.
• A plant population of 120 plants/m2 was shown to yield more than higher plant populations whilst also minimising lodging.

• In 2015, two spring irrigations produced the highest wheat grain yield (7.61 t/ha), but one irrigation provided the highest water use efficiency (1.7 t/ML).
• Ponding irrigation water for 48 hours to induce waterlogging did not reduce grain yield in this experiment, but increased water use and reduced water use efficiency by 25%.
• If the number of spring irrigations is limited, it is important to find a balance between irrigating before significant moisture stress occurs and ensuring adequate moisture is available during flowering.
   

• Suntop was the highest yielding variety (4.48 t/ha).
• Lancer achieved high protein, high test weight and low screenings at all nitrogen application rates.
• Grain yield increased as nitrogen application rates increased, but there was no significant increase in yield above 20 kg N/ha applied nitrogen.
• Applying 160 kg N/ha resulted in a yield decrease.

• Sowing date and varietal phenology both affected the exposure of canola to rain days and potential disease infection.
• Early sowing increased the level of pod blackleg infection.
• Early sowing increased sclerotinia infetion in the early flowering variety Hyola 575CL but not in the slower variety Pioneer 45Y88 (CL). 
• Grain yield was higher from the later sowing date (22 April) than the early sowing date (7 April).
• Grain yild was closely correlated to total biomass accumulation, which was greater from the 22 April sowing time than 7 April sowing time.

• Early sown (9 April) Pioneer 45Y88 (CL) yielded similarly to later sown (20 April) Pioneer 45Y88 (CL) and Hyola 575CL.
• The irrigation treatment that stored 20mm plant available water did not increase grain yield or oil concentration.
• The maturity biomass was higher from the later sowing date, but the harvest index was slightly higher from the early sowing date.

 

• Variety phenology and sowing date need to match to avoid plants flowering and podding during periods of severe frost. The highest yield in 2017 came from the 6 April sowing of the long season varieties Archer and ATR WahooA that flowered in early August.

• ATR Stingray and Nuseed® Diamond flowered earlier than the optimum start of flowering (OSF) date (28 July) from both the 6 April and 20 April sowing dates with significant frost damage incurred at both sowing dates.

• Canola varieties have the ability to recover from severe frost damage where soil water is not limited.

• 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.

• Varietal selection again proved to be the major factor in achieving higher wheat yields in the second year of experiments in irrigated wheat production at Leeton.
• CobraA was the highest yielding variety in this experiment but CorackA, SuntopA and the durum breeding line 280913 also performed very well.
• Correct nitrogen timing significantly increased grain yield, grain protein and significantly reduced lodging.
• Managing plant population also significantly reduced lodging

• Varietal selection again proved to be the strongest determinant of irrigated canola grain yield in the second year of experiments at Leeton.
• The three highest yielding varieties were Nuseed® Diamond, Hyola® 50 and Nuseed® GT-50.
• Sowing time and variety interaction affected lodging, grain yield and harvest index (HI).
• Plant population alone only affected lodging but the variety interaction affected lodging and the harvest index.

• Total number, severity and length of frosts increased as surface residues increased.
• Increasing the amount of surface residue delayed plant growth, lengthened growth phase duration, and overall time to maturity for both chickpea and lentil.
• For both chickpea and lentil, high surface residues, above 9 t/ha, significantly reduced biomass accumulation and grain yield.

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• 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.
   

• Nitrogen fertiliser management influences crop nitrogen uptake at defoliation and cotton lint yield
• Irrigation management did not influence crop nitrogen uptake at defoliation, but significantly influenced cotton lint yield.
• The apparent nitrogen fertiliser recovery was 46% where the optimum fertiliser nitrogen rate was applied
• Seed nitrogen concentration and nitrogen removal was influenced by nitrogen fertiliser application rate, but the effect was not consistent with rate.

• Although time of heading and flowering are considered the most sensitive stages for frost damage in cereals, sensitivity to early frost damage occurs from the start of stem elongation and is referred to as ‘stem frost’.

• Stem frost can be minimised by matching sowing date and cultivar phenology so that stem elongation starts after the period of greatest frost risk.

• Varieties that started stem elongation early (fast developing varieties sown early) were exposed to an increased number of frosts during the susceptible development stages, whilst winter types sown early had an extended vegetative period and were not exposed to the same frost risk, which reduced damage from stem frost.

• Crops can recover from stem frost where there is moisture available to support new tiller growth. However, the resulting effect on phasic development stage synchrony leads to delayed maturity and harvest issues.

• There was no observed difference in frost tolerance of specific cereal species observed in 2017.

• Stubble rentention increased the severity of frost events in experiments over two years
• There was no difference in floret sterility due to stubble treatment, but grain yield was highest where stubble was removed by burning. 
• Stubble rentention reduced the amount of heat stored in the soil during spring. With less heat stored there is less capacity for energy release at night to buffer against frost damage.
• Consider management strategies that avoid frost (e.g. crop choice, sowing date, variety choice) where high stubble loads are retained at sowing. 

• Thrips pressure reached the positive control threshold of one thrips per plant in late October while plants were at the cotyledon to 1-leaf stage.
• Thrips pressure reached the industry threshold of 10 thrips per plant in mid-November when plants were at the 4–5-leaf stage.
• Onion thrips were the dominant thrips species observed during monitoring.
• Western flower thrips (WFT) constituted less than 5% of thrips monitored.
• There was no yield difference between sprayed and unsprayed plots.

• Thrips pressure was lower in the earlier planted Whitton site.
• Thrips pressure reached the industry control threshold of 10 thrips/plant on 3 November while plants were still at the cotyledon to 1-leaf stage at the Darlington Point site, and only in some plots at Whitton on 9 November and most plots on 23 November when plants were at the 6–8 leaf stage.
• Onion thrips were the dominant thrips species observed during monitoring.
• Western flower thrips constituted less than 5% of thrips monitored.
• There was no yield difference between sprayed and unsprayed plots.

• The ideal sowing time for soybeans in southern NSW is from mid-November to early December.
• Delaying sowing until late December can result in reduced grain yield.

• Ornithopus sativus (French serradella) and O. compressus (yellow serradella) had a significantly high root hair cylinder volume compared with Trifolium subterraneum, which provides for a great phosphorus (P) foraging ability and helps explain why the Ornithopus species has lower critical P requirements than T. subterraneum.

• Flowering time is determined by responses to vernalisation, photoperiod and earliness per se.
• Match variety and sowing time to ensure flowering occurs during the optimal period for your growing environment.

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

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

KEY FINDINGS:

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

Conclusions

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

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

 

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

 

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

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

• Phenology and grain yield responses were significantly influenced by seasonal conditions in 2019.
• Severe heat stress and terminal drought conditions favoured faster developing spring genotypes, which achieved the highest grain yields in 2019.
• Grain yield responses varied in response to sowing date, and highest yields occurred when phenology was matched with recommended sowing windows.

• The most intense of three heat events avegarged 35.5 degrees celcius and reduced grain numbers per spikelet by 21%.
• Significant genetic variation was observed for floret sterility induced by natural heat events. The variety Halberd was identified as most heat tolerant and Westonia as most heat sensitive.
• The results indicate a genetic variation that could be exploited to improve wheat crop resilience under heat stress. 

• Sowing date, particularly for mid–late maturing varieties, was found to be a significant determinant of grain yield potential, with yield reductions of >25% observed due to a delayed sowing date (8 May vs. 7 June).
• Variety and sowing date in particular affected grain quality parameters, with a significant increase in the level of screenings for all varieties when the sowing date was delayed.
• Higher plant populations had a greater influence on grain yield when the sowing date was delayed. Yield potential was optimised at 200 plants/m2 for a 7 June sowing date vs. 100 plants/m2 for the earlier 8 May sowing date, supporting the principal of increasing targeted plant populations when sowing is delayed.
• Altering variety and maturity type, and increasing targeted plant population in response to a delayed sowing date did not fully compensate for yield losses associated with a delayed vs. timely sowing date.

Conclusions:

Results from this experiment highlight the importance of timely sowing, particularly for mid–late maturing varieties. Yield reductions of approximately 1.3 t/ha averaged across plant population treatments were recorded for the mid–late maturing varieties LRPB LancerA and EGA GregoryA with delayed sowing, which equates to a 25% and 26% yield decline, respectively. Similarly, the late maturing variety EGA EaglehawkA suffered a yield penalty of around 22% (0.98 t/ha) whilst the mid maturing variety SuntopA suffered a 14% (0.70 t/ha) yield reduction due to delayed sowing. In comparison, the earlier maturing varieties LRPB DartA and LRPB SpitfireA suffered only minimal yield reductions when SD was delayed. Importantly however, the earlier maturing varieties did not exhibit any yield advantage over the later maturing varieties in SD 2 and were significantly lower yielding than these varieties at SD 1. Temperature and plant available water during anthesis/grain fill would also have affected both yield potential and grain quality parameters, with limited effective in-crop rainfall in September/October, and temperatures exceeding 35 °C for an extended period from 4 October. The longer season variety EGA EaglehawkA in particular had high screenings for both SDs, and also produced a low yield in SD 2, reinforcing the need to sow this variety early due to its lack of adaptability under unfavourable conditions. Increasing plant population had a greater influence on GY when SD was delayed, with yield potential optimised at 200 plants/m2 in SD 2 vs. 100 plants/m2 in the earlier SD 1, supporting the principal of increasing targeted plant populations with delayed sowing. These findings further emphasise the advantage of planting early in the sowing window compared to delayed sowing just simply in terms of input seed requirements. Variety selection and sowing date particularly affected grain quality parameters and screenings. There was a significant increase in the level of screenings for all varieties when sowing was delayed. LRPB LancerA was the only variety in this experiment that achieved screenings of <5%, but only at SD 1. All other varieties, including LRPB LancerA in SD 2, exceeded the critical 5% screenings receival standards level. LRPB LancerA appears to have excellent grain stability with significantly lower screenings than either EGA GregoryA or SuntopA. Findings from this experiment indicate that there were differences between varieties in terms of grain stability, due possibly to variations in kernel shape/plumpness and or kernel weight stability. These results also highlight the adaptability of some of the mid–late season 16 | NSW Department of Primary Industries varieties, and the yield and quality advantages of sowing these varieties early, compared with sowing earlier maturing varieties later

• Fungicide reduced disease levels in all varieties, but failed to eliminate disease completely.
• Observed differences in disease levels agreed with published variety resistance ratings.
• Early infection of yellow leaf spot (YLS) caused high yield losses in the more susceptible varieties.
• Variety selection will always play an important role in high risk areas.
• Crop rotation and best practice methods are required to maximise the benefits of correct variety selection.

• Fungicide reduced disease levels in all varieties, but failed to eliminate the disease completely.
• Observed differences in disease levels were broadly in agreement with published variety resistance ratings.
• Yield losses were observed in the more susceptible varieties due to early disease development.
• Low disease levels from an early stage can cause yield losses.
• Variety selection will always play an important role in managing disease in high risk areas.

• Sowing date and variety maturity choice is a balance between the risk of frost versus terminal heat stress.
• Earlier sowing can increase frost risk, but also generally maximises yield potential and reduces the extent of yield loss from crown rot.
• Cereal crop and variety selection can have a significant impact on yield where there are high levels of crown rot infection.
• Durum wheat, barley or bread wheat varieties with increased susceptibility to crown rot, should only be grown in paddocks known to have lowrisk inoculum levels based on testing (e.g. PreDicta B).
• All winter cereal varieties are susceptible to crown rot infection and will not significantly reduce inoculum levels for subsequent crops. Cereal crop and/or variety choice is not the sole solution to crown rot.

• The quicker maturing varieties LRPB DartA, HatchetA LivingstonA, MaceA, SceptreA, MitchA and SuntopA were generally lower yielding than other entries at SD1, but were more yield competitive with other entries at SD2 and SD3.
• The longer season varieties EGA WedgetailA (6.08 t/ha) and EGA EaglehawkA (5.88 t/ha) were the highest yielding varieties at SD1, followed by CutlassA (5.51 t/ha) and LRPB FlankerA (5.36 t/ha).
• The mean yield at SD1 (4.89 t/ha) was not significantly different from SD2 (4.63 t/ha), but SD3 (3.56 t/ha) was significantly lower yielding than either SD1 or SD2.
• All varieties yielded their lowest from SD3.
• Protein percentages were low to moderate (mean of 9.8% for SD2 and 10.3% for SD1) with no significant difference from SD for any of the entries