• Sunflower yields were greatly affected by the various defoliation treatments, ranging from 0.12 t/ha to 0.97 t/ha.
• Reductions in yield, of between 55% and 82% compared with the control resulted from total leaf removal at all three of the targeted growth stages (budding, start of flowering and flowering completion) as well as removing two-thirds of the leaves at budding.
• There was no negative effect on grain yield from removing the bottom third of leaves at budding or the start of flowering. Removing the bottom third of leaves at the start of flowering actually provided a slight yield advantage over the control treatment. The largest effect on plant height, head diameter and head arc length were caused by removing all leaves at the budding stage.

• Mungbean yield potential ranged from a low of 0.81 t/ha up to a high of 2.70 t/ha in three years of irrigated variety evaluation experiments at Trangie in the Macquarie Valley.
• Jade_AUA (released 2013) is the recommended variety for Macquarie Valley mungbean growers with the highest yield potential, largest seed size (an important quality attribute for marketing) and best disease tolerance package. CrystalA would be an adequate second-best option based on yield and potential seed size.
• Niche mungbean varieties such as Regur (black gram type), and the two small-seeded lines Celera IIA and Green DiamondA, would have to command a substantial premium for their respective seed quality attributes to compensate for the poorer yield potential demonstrated in these experiments.

• Sunflower grain yield averaged 1.07 t/ha at this site with the highest yields obtained from the control and the treatments where only the bottom one third (1/3) of leaves were removed.
• The total leaf removal treatments had the largest effect on yield, at worst yielding only 0.16 t/ha.
• Removing all leaves at budding or at the start of the flowering growth stages had the largest effect on plant structures.
• Total leaf removal at the end of flowering had the largest effect on 1000 grain weight and test weight.

• Sunflower yields were very low at this site in 2015–16, averaging 0.24 t/ha, and overall variability was very high.
• The total removal of leaves at the budding stage had the largest impact on plant structures; plant height, head diameter and arc length.

Key findings:

• Nitrogen (N) decision making requires a good understanding of background soil and plant science, and soil test interpretation.
• Training for new agronomists needs to be a priority issue.
• Senior NSW agronomists identified crop yield expectation as guided by soil moisture at sowing (or at the time of N decision making) as the most important determinant of N fertiliser requirement.
• Further research is needed to increase the understanding of how management practices affect potentially large gaseous N losses. 
• Changing from legume pasture-crop sequences to continuous cropping in many central and southern areas of New South Wales is posing new questions for managing N supply. The absence of N-fixation by pasture legumes is seen as a substantial loss of N-buffering capacity.
• Despite most advisers choosing soil testing as a key approach for determining N fertiliser required, many of their clients had a lower confidence in soil testing, citing ‘high perceived variability in soil nitrate results in the lead up to sowing’.

• Conclusions and Recommendations

  Senior advisers highlighted the importance of quality training in N decision-making, understanding the background soil and plant science involved, and soil test interpretation for the next generation of agronomists, with training courses including representation from highly experienced local agronomists.
• The understanding of gaseous N losses requires further research, development and extension to the grains industry. Recent field research in the north was limited in scope and produced challenging outcomes that can potentially lead to large practice changes in when and how N fertiliser is applied. Further research and development work is warranted to answer more of the practical questions growers and advisers are asking in regards to losses associated with various alternative practices.

• The northern results on N loss pathways are less relevant to advisers in the central and southern regions where N application timing, soil type and climatic differences are generally quite different from the dominant medium-heavy clays of the north. New N loss research is recommended for the lighter textured soils in regards to the potential for N volatilization losses from surface N application of various products. Economic outcomes from the various strategies being practiced are also needed. Nitrogen loss research should focus less on expensive slow-release products and more on optimising results from urea, the cheapest N source.

• Research into better soil water measurement was seen as a priority area, especially given the importance all advisers place on knowing this when making expensive N-fertiliser decisions for a coming cropping season. Zonal management within paddocks is not possible with single site characterisations, so atypical areas of paddocks are over or under-fertilised.

• The very early application of N fertiliser ahead of a winter cropping season is well established, but what is not known is how well the subsoil N may be protected or at risk from denitrification in flooding events. Also, better knowledge on specific N use within the profile during the cropping season will help growers to know when late-applied N is likely to be inaccessible to crop use.

• Nitrogen mineralisation was highlighted by agronomists from all three regions as an area for greater understanding with regards to the differences caused by climatic conditions, especially rainfall. They also require better understanding of the N produced from both native organic matter and recent legume pasture residues.

• There are a number of good decision support tools available currently, with several advisers suggesting that combining the best points of each into one package, even one available as an app, would be highly useful, particularly one with good grower-friendly reports.

• Many farmers have low confidence in soil testing.  This may be related to a range of factors from poor sampling strategies, to poor sample handling, to poor service from laboratory analysts, to insufficient sample numbers or poor interpretation of the results. It is seen as an expensive option for many, with some advisers looking for quicker and cheaper means of estimating soil mineral N.

• Variety-specific N management packages were seen by some senior advisers as key areas for continued research funding, as results from some new varieties have been quite different in terms of N uptake and protein outcomes.

• 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.

• In a year with high rust pressure, fungicide application provided beneficial to all genotypes, even those with a good level of rust resistance.
• Several advanced breeding lines from the northern breeding program show promise, with high yield and large seed size combined with rust and chocolate spot resistance equal to or better than the current northern varieties.

Conclusion:

The high rust pressure and frequent rainfall towards the end of the season was likely responsible for the poor fungicide response in the LF experiment in terms of reducing symptoms and improving yield and seed size. In the HF experiment, mancozeb and
tebuconozole were most effective overall in reducing symptoms and improving yield and seed size. Four of the five fungicides were effective in increasing yield in the HF experiment compared with only one in the LF experiment, indicating the need for repeated sprays when disease pressure is high.

Note that the permit for tebuconazole allows for only three applications of 145 mL/ha in commercial crops.

 

• Adding phosphorus (P) did not significantly increase yield or seed weight in the varieties PBA WardaA and PBA NasmaA.
• PBA NasmaA produced greater yield and seed size than PBA WardaA.

Conclusions:

In this experiment, additional P did not increase yield, however, on a lower P site, a positive response to P might occur. The reduction in yield caused by adding N might be due to reduced nodulation in N-treated plots, although nodulation was not measured in this trial. The greater yield and seed size of PBA NasmaA compared with PBA WardaA supports other experimental data.

• In a year of high disease pressure, most fungicides did not provide a yield and seed size benefit when used at low frequency.
• A high frequency fungicide strategy provided yield benefit using a number of products.
   

•  A survey of 80 winter cereal crops across central and northern NSW in 2016 established that low levels (generally <1%) of Fusarium head blight (FHB) were evident with the causal pathogen predominantly being Fusarium pseudograminearum (Fp).
• This was the crown rot fungus (Fp), reminding growers that it does not disappear in a wet season.
• FHB infection caused by Fp has a reduced risk for mycotoxin accumulation in infected grain, but could have detrimental impacts on crop establishment if seed is retained for planting.
• Planting Fusarium-infected grain can also introduce seed-borne crown rot infection into clean paddocks, negating the rotational benefits associated with growing non-host crops.
   

• The starting soil nitrogen (N) at this site was 73 kg N, which was sufficient to supply the average crop yield of 2.1 t/ha, which was achieved.
• Consequently, there was no response to any of the nitrogen treatments applied.
• Hybrid selection had a major impact on plant structures, grain yield and quality. Pioneer 1467 produced more tillers than the other two hybrid maize varieties.
• Pacific 606 produced the highest grain yield at 2.65 t/ha and also had the highest 1000 grain weight and lowest screenings of the three hybrid maize varieties examined.
   

KEY MESSAGES:

• Richmond produced an average yield 7% higher than Soya 791 in advanced variety evaluations at early sowing dates (first week in December) over six seasons.
• Richmond produced an average yield 7.7% higher than Asgrow A6785 in advanced variety evaluations at late sowing dates (mid January) over eight seasons.
• In on-farm experiments, Richmond yielded 16% higher than Soya 791 in a wide-row system on the northern slopes, and 7% higher than Asgrow A6785 in a narrow-row coastal system.
• In addition to higher yield potential, Richmond is tolerant to lodging and pre-harvest weather damage, has clean leaf drop, large seed size and high protein, and is resistant to powdery mildew. This combination of traits provides greater crop security and a full range of market options for growers, and high quality grain for buyers and processors.

CONCLUSIONS; 

The Australian soybean variety RichmondA produces large grain (22 g/100 seed) with a clear hilum and high levels of protein (42% dry matter), which is suitable for all markets including human consumption and export. The traditional variety, Asgrow A6785, has small grain (<16 g/100 seed) with a brown hilum and protein levels less than 40%, which limits the range of markets to which it is suited. The traditional variety, Soya 791, has average sized grain Agronomy NORTHERN NSW RESEARCH RESULTS 2017 | 53 (19 g/100 seed) with a light brown hilum and high levels of protein (42%). Both A6785 and Soya 791 are prone to excessive vegetative growth, especially at an early sowing date. However, this is not necessarily converted into grain yield as demonstrated in the on-farm experiment at Harwood. RichmondA is superior to A6785 and Soya 791 in terms of grain yield, tolerance to lodging, tolerance to pre-harvest weathering and clean leaf drop. RichmondA offers a summer legume option with high yield and high grain quality for early, mid or late sowing windows in northern New South Wales. The variety’s performance was not adversely affected by the range of soil types and farming systems reported in this paper; it was superior to A6785 and Soya 791 in all situations. RichmondA is resistant to powdery mildew. This package of traits represents a significant advance in soybean varieties for the North Coast, Tablelands, Northern Slopes and Liverpool Plains production regions of northern New South Wales. The results of the on-farm experiment of RichmondA versus Soya 791 in a wide spacing, single row system at Oakwood demonstrates the variety’s ability to compensate for wide rows and the associated lower plant populations in dryland systems. Row spacing and plant population interactions of new soybean and mungbean varieties are being investigated in the current NSW DPI–GRDC project DAN00171

• Richmond produced an average yield 7% higher than Soya 791 in advanced variety evaluations at early sowing dates (first week in December) over six seasons.
• Richmond produced an average yield 7.7% higher than Asgrow A6785 in advanced variety evaluations at late sowing dates (mid January) over eight seasons.
• In on-farm experiments, Richmond yielded 16% higher than Soya 791 in a wide-row system on the northern slopes, and 7% higher than Asgrow A6785 in a narrow-row coastal system.
• In addition to higher yield potential, Richmond is tolerant to lodging and pre-harvest weather damage, has clean leaf drop, large seed size and high protein, and is resistant to powdery mildew. This combination of traits provides greater crop security and a full range of market options for growers, and high quality grain for buyers and processors.

Conclusions:

The Australian soybean variety RichmondA produces large grain (22 g/100 seed) with a clear hilum and high levels of protein (42% dry matter), which is suitable for all markets including human consumption and export. The traditional variety, Asgrow A6785, has small grain (<16 g/100 seed) with a brown hilum and protein levels less than 40%, which limits the range of markets to which it is suited. The traditional variety, Soya 791, has average sized grain Agronomy(19 g/100 seed) with a light brown hilum and high levels of protein (42%). Both A6785 and Soya 791 are prone to excessive vegetative growth, especially at an early sowing date. However, this is not necessarily converted into grain yield as demonstrated in the on-farm experiment at Harwood.

RichmondA is superior to A6785 and Soya 791 in terms of grain yield, tolerance to lodging, tolerance to pre-harvest weathering and clean leaf drop. RichmondA offers a summer legume option with high yield and high grain quality for early, mid or late sowing windows in northern New South Wales. The variety’s performance was not adversely affected by the range of soil types and farming systems reported in this paper; it was superior to A6785 and Soya 791 in all situations. RichmondA is resistant to powdery mildew. This package of traits represents a significant advance in soybean varieties for the North Coast, Tablelands, Northern Slopes and Liverpool Plains production regions of northern New South Wales.

The results of the on-farm experiment of RichmondA versus Soya 791 in a wide spacing, single row system at Oakwood demonstrates the variety’s ability to compensate for wide rows and the associated lower plant populations in dryland systems. Row spacing and plant population interactions of new soybean and mungbean varieties are being investigated in the current NSW DPI–GRDC project DAN00171

Key findings

• Yield loss from crown rot ranged from 7.6% in the bread wheat variety LRPB SpitfireA up to 29.1% in the barley variety CommanderA. • Bread wheat variety choice affected yield in the presence of high levels of crown rot infection with nine entries being 0.30 t/ha to 1.33 t/ha higher yielding than the susceptible bread wheat variety EGA GregoryA.

• Grain protein levels varied from 12.0% in MitchA up to 15.8% in the recently released durum variety DBA LillaroiA. Crown rot infection did not affect any grain protein level in any entry.

• Screening levels varied from 2.2% in the barley variety CompassA up to 9.5% in the bread wheat line LPB12-0494.

• Crown rot infection did not affect screening levels in any entry.

Conclusions

Cereal crop and variety choice provided a 7–33% yield benefit over growing the susceptible
bread wheat variety EGA GregoryA under high levels of crown rot infection at Bullarah in
2016. This could have maximised profit in the growing season but will not reduce inoculum
levels for subsequent crops, because all winter cereal varieties are susceptible to crown rot
infection. 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.

• Yield loss from crown rot ranged from not significant in four of the bread wheat varieties up to 14.9% in the barley variety CompassA. • Bread wheat variety choice affected yield in the presence of high levels of crown rot infection with eight entries being between 0.29 t/ha and 0.76 t/ha higher yielding than EGA GregoryA.
• Grain protein levels varied from 11.9% in BeckomA up to 14.7% in the recently released durum variety DBA LillaroiA. Crown rot did not affect protein levels in any other entry.
• Screening levels varied from 4.4% in the barley variety CompassA and bread wheat variety CoolahA up to 9.3% in the barley variety SpartacusA. Crown rot did not affect screenings in any other entry.

Key findings

• Yield loss from crown rot ranged from not significant in the barley varieties SpartacusA and CommanderA up to around 20% in the barley variety CompassA and bread wheat varieties EGA GregoryA and LRPB FlankerA.

• Bread wheat variety choice affected yield in the presence of high levels of crown rot infection with five entries being between 0.32 t/ha to 0.57 t/ha higher yielding than the susceptible bread wheat variety EGA GregoryA.

• Grain protein levels varied from 11.3% in MitchA up to 14.9% in LRPB SpitfireA. Crown rot infection did not affect protein levels in any entry.

• Crown rot infection increased the level of screenings in all four barley varieties and the two bread wheat varieties SunmateA and LRPB ReliantA.

Conclusions

Cereal crop and variety choice provided a 7–13% yield benefit over growing the susceptible
bread wheat variety EGA GregoryA under high levels of crown rot infection at Garah in 2016.
This could have maximised profit in this growing season, but will not reduce inoculum levels
for subsequent crops because all winter cereal varieties are susceptible to crown rot infection.
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.

• Yield loss from crown rot ranged from not significant in the variety DBA LillaroiA and seven of the 13 bread wheat varieties, up to 32.9% in the durum variety JandaroiA.
• Only the bread wheat variety MitchA was higher yielding (0.41 t/ha) than the susceptible bread wheat variety EGA GregoryA in the presence of high levels of crown rot infection.
• Grain protein levels were low across the site and varied from 7.7% in MitchA up to 10.1% in the durum line 190873. Crown rot infection did not affect protein levels in any entry.
• Crown rot infection caused a small (1–2%), but significant, increase in the level of screenings in the barley variety La TrobeA, and 10 of the 13 bread wheat entries.
   

•  Yield loss from crown rot ranged from not significant in the barley variety CompassA, durum entries 190873 and JandaroiA and six of the bread wheat varieties, up to 19.7% in the barley variety CommanderA.
• Only the bread wheat variety BeckomA was higher yielding (by 0.58 t/ha) in the presence of high levels of crown rot infection than the susceptible bread wheat variety EGA GregoryA.
• Grain protein levels were very low across the site (average 8.2%) and varied from 7.5% in LRPB ReliantA up to 8.9% in LRPB SpitfireA. Crown rot did not affect protein levels in any entry.
• Screening levels were very low across entries, but crown rot infection caused a small (0.5–1.3%), yet significant, increase in the level of screenings in the barley varieties CompassA and CommanderA, as well as in the bread wheat varieties CoolahA and LRPB SpitfireA.

CONCLUSIONS:

Cereal crop and variety choice affected yield in the absence and presence of added crown rot inoculum, which differed by 1.41 t/ha and 1.30 t/ha, respectively between the best and worst entries. Only the bread wheat variety BeckomA provided a yield benefit (15%) over growing the susceptible bread wheat variety EGA GregoryA under high levels of crown rot infection at Merriwa in 2016. This could have maximised profit in this growing season, but will not reduce inoculum levels for subsequent crops because all winter cereal varieties are susceptible to crown rot infection. 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.

•  Yield loss from crown rot ranged from not significant in the bread wheat varieties MitchA and BeckomA up to 18.6% in the bread wheat variety LRPB FlankerA.
• The two barley varieties Spartacus A and La TrobeA along with nine of the bread wheat entries were higher yielding (0.28 t/ha to 0.86 t/ha) in the presence of high levels of crown rot infection than EGA GregoryA.
• Grain protein levels were relatively low at across the site which varied from 9.2% in CoolahA up to 11.5% in the barley variety SpartacusA . Protein levels in all other entries were not affected by crown rot infection.
• Crown rot infection caused a small (0.6 to 1.4%) but significant increase in the level of screenings in the four barley varieties and four of the thirteen bread wheat entries but remained below 5% for all entries.

Conclusions

Cereal crop and variety choice provided a 6–20% yield benefit over growing the susceptible bread wheat variety EGA GregoryA under high levels of crown rot infection at Parkes in 2016. This could have maximised profit in this growing season but will not reduce inoculum levels for subsequent crops because all winter cereal varieties are susceptible to crown rot infection. 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.

Key findings

• Yield loss from crown rot ranged from not significant in five of the bread wheat varieties, the barley variety CommanderA and the durum variety JandaroiA up to 12.9% in the bread wheat variety EGA GregoryA.

• The recently released durum variety DBA LillaroiA produced a protein level of 15% which was over 1% higher than the two other durum entries JandaroiA and 190873.

• Crown rot infection did not significantly impact on the level of screenings in any of the entries due to limited expression under the wet seasonal conditions at this site in 2016. However, genetic differences were evident with screening levels which ranged from 3.2% in the durum line 190873 up to 17.6% in the bread wheat variety BeckomA.

Conclusions

Cereal crop and variety choice affected yield in the absence and presence of crown rot infection, which differed by 2.26 t/ha and 2.24 t/ha, respectively between the best and worst entries. The three durum entries were higher yielding relative to bread wheat and barley entries in both the added CR and no added CR treatments at this site in 2016. This was likely due to seasonal conditions (near full soil water profile at sowing plus 472 mm of in-crop rainfall), which limited crown rot expression.

Cereal crop and variety choice still provided a 9% to 35% yield benefit over growing the susceptible bread wheat variety EGA GregoryA under high levels of crown rot infection at Tamarang on the Liverpool Plains in 2016. This can maximise profit in the current season but will not reduce inoculum levels for subsequent crops, because all winter cereal varieties are susceptible to crown rot infection. 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.

Key findings

• Yield loss from crown rot ranged from not significant in the bread wheat variety LRPB ReliantA up to 16.9% in the barley variety CompassA

 • Bread wheat variety choice affected yield in the presence of high levels of crown rot infection with three entries being between 0.45 t/ha and 0.85 t/ha higher yielding than the susceptible bread wheat variety EGA GregoryA.

• Grain protein levels were low across the site (mean of 9.8%) and varied from 8.7% in MitchA up to 10.6% in LRPB SpitfireA Crown rot infection did not affect protein levels in any entry.

• Crown rot infection caused a small (1–4%), but significant increase in screenings in the barley variety La TrobeA and all of the 13 bread wheat entries.

• Seasonal conditions reduced stress during grain fill at this site in 2016, which limited the effects from infection on yield.
• Although the effect of crown rot infection on yield was not significant, there was still a 52% (1.76 t/ha) difference between the overall yield of the best and worst entries.
• Grain protein levels were relatively low across the site, varying from 7.8% in MitchA up to 9.8% in the durum line 190873. Crown rot did not affect protein levels in any other variety.
• Crown rot infection caused a moderate (2–6%) increase in the level of screenings in 10 of the 13 bread wheat entries.

Conclusions:

Cereal crop and variety choice affected yield at this site in 2016, which differed by 1.76 t/ha (52%) between the best (SpartacusA) and worst (DBA LillaroiA) entries when averaged across CR treatments. CR treatment did not significantly affect yield in any of the entries due to seasonal conditions (~120 mm of plant available water at sowing plus 555 mm in-crop rainfall), which limited stress during grain filling. The added CR treatment also did not affect grain protein levels, but resulted in a modest 2–6% increase in the level of screenings in 10 of the 13 bread wheat entries.

It should be remembered that cereal crop and variety choice in paddocks with a medium crown rot risk can maximise profit in the current season, but will not reduce inoculum levels for subsequent crops because all winter cereal varieties are susceptible to crown rot infection. 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. 

• 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®.

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.

• 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

Key findings:

• In a wet season, substantial yield losses (94%) from Phytophthora root rot (PRR) occurred in susceptible chickpea varieties such as PBA BoundaryA.
• Varieties with improved resistance to PRR (PBA HatTrickA and YorkerA) can also have large yield losses (68–79%) in a season highly conducive to PRR.
• Although yield losses will occur in seasons highly conducive to PRR, crosses between chickpea and wild Cicer species, such as the PBA breeding line CICA1328, currently offer the best levels of PRR resistance.

Summary

Under conditions that are highly conducive to PRR, substantial (94%) yield losses occur in susceptible varieties such as PBA Boundary.  However, significant losses (68-79%) can also occur in varieties with improved resistance to PRR (PBA HatTrick and Yorker).  Crosses between chickpea and wild Cicer species such as the PBA breeding line CICA1328 offer the best resistance to PRR.

• Durum varieties displayed differential grain quality and yield responses to time of sowing (TOS) and nitrogen (N) management.
• DBA AuroraA appears to offer good yield potential, but exhibits an increased risk of screenings with increasing rates of N application at sowing or when N is applied before stem elongation (GS31). It also appears to have an increased potential for lower grain protein concentrations (GPC) due to yield dilution under high yielding situations.
• A strategy involving a split application of N at sowing and either GS31 or GS39, could reduce the potential for screening issues in DBA AuroraA while maintaining adequate GPC.
• Findings from this experiment further highlight the need to sow appropriate variety maturity types within their recommended sowing windows.
   

• Durum varieties (CaparoiA, DBA AuroraA, DBA LillaroiA and JandaroiA) displayed differential grain quality and yield responses to time of sowing (TOS) and nitrogen (N) management. Increased screenings (>5%) were the most common cause of quality downgrades.
• DBA AuroraA, due to increased risk of screenings (>5%) in part because of reduced grain size, would appear to offer less flexibility in terms of agronomic management, specifically delayed sowing and N management.
• The newly released Northern Durum breeding program variety DBA LillaroiA appears to offer excellent grain size and grain stability, achieving low screenings from a delayed sowing and high N rates.
• Results also highlight the need to sow varieties within recommended sowing windows. An earlier than recommended sowing date of May 19 for the Liverpool Plains resulted in yield losses of ~25% averaged across N treatments for earlier maturing varieties such as JandaroiA and DBA LillaroiA, with possible grain quality implications (e.g. increased screenings).

Key findings:

• Increasing levels of inoculum (oospores/ plant) of Phytophthora medicaginis (P. med) was strongly correlated with the decreasing yield of Yorker, a moderately resistant chickpea variety.
• An inoculum level of 660 oospores/plant (PreDicta B >5000 P. med copies/g soil) at sowing significantly reduced yield compared with lower inoculum levels under both dryland and irrigated conditions.
• These findings provide further evidence that the PreDicta B P. med test will be a useful tool for growers to determine their risk of Phytophthora root rot before sowing chickpeas.
• Note: the SARDI PreDicta B test for Phytophthora medicaginis is under development and is not yet available commercially.

Summary

P.med inoculum level, PRR disease and yield

Can the P.med DNA soil test predict the risk of Phytophthora root rot?  Based on the results of this trial with Yorker (MR) and the 2014 Tamworth trial with Sonali (S), the answer is YES.  For Yorker significant yield loss can be expected with starting (pre-sow sampling) inoculum levels above ca 3000 P.med DNA sequences/g soil (ca 130 oospores/plant). However, these values may need to be interpreted with some caution as seasonal conditions will modify outcomes, for instance in a dry season less disease may develop from the same amount of inoculum.

As Phytophthora can reproduce rapidly and cause new infections over a relatively short period there was concern that under PRR conducive conditions (a wet season), that low initial levels of inoculum could catch up to high initial levels as cause similar disease severity and yield loss.  The 2015 season was wet but not very wet, under these conditions there was separation in the disease and yields of the low and high inoculum treatments.

P.med DNA detection in commercial in paddocks and disease risk determination

These second season of detection capability results for the soil P.med DNA test were again generally promising, with most samples with positive and negative P.med DNA results corresponding to expected P.med isolation results.  However, results for some samples indicate that further work is required to a) identify what factors may contribute to false negative results and b) determine if false positives are due to the presence of dead or inactive P.med DNA

The DNA result for a soil sample from a paddock can only provide an indication of inoculum concentration and disease risk for the areas of the paddock which were sampled.  Therefore, the spread and locations of sampling across a paddock will affect how representative DNA results are for a paddock.  Because of the risk of rapid PRR disease buildup following wet conditions it may be appropriate to treat a negative Predicta B^® test result as indicating a low risk rather than a nil risk, as the pathogen could still be in areas of the paddock that were not sampled and so still cause PRR and reduce yield. 

Work in 2016 will evaluate maximising the probability of detecting P. med by targeting those areas of the paddock where P.med is more likely to occur.  The pathogen thrives in high soil moisture contents and so often occurs in low lying regions of paddocks where pooling following rain may occur.  The pathogen also carries over from season to season on infected chickpea volunteers, lucerne and, native medics.  Including low lying areas and weedy areas of paddocks during PreDicta B^® soil sampling may provide the best strategy to detecting P. med and so identifying a paddocks disease risk of PRR in chickpea.

Key messages:

• Treating EGA GregoryA seed with Rancona Dimension reduced establishment losses associated with the addition of crown rot inoculum to 7% compared with 26% when no seed treatment was used.
• In this instance, Rancona Dimension did not provide a significant or consistent yield benefit in the presence of high levels of crown rot infection across the 12 trial sites in 2015.
• Growers should not expect Rancona Dimension to provide a significant and consistent reduction in yield loss from crown rot infection when used as a standalone management strategy.
• Growers considering the use of Rancona Dimension should follow the manufacturer’s advice and only consider it as part of an integrated management strategy against crown rot.

Conclusions

Rancona® Dimension is registered in Australia for the suppression of crown rot infection. Rancona® Dimension reduced establishment losses associated with severe early infection, created by the addition of crown rot inoculum to the seed furrow at sowing, to 7% compared to 26% in the absence of a seed treatment. Further research is required to determine if this improvement in establishment is associated with reduced Fusarium seedling blight. It should also be established whether such severe establishment losses are an artefact of the inoculation process used in the trials or occurs naturally in paddocks with high stubble-borne inoculum loads. In a separate larger trial conducted at Tamworth in 2015 in which infected stubble at the surface was the inoculum source Rancona® Dimension did not have a significant impact on the establishment of EGA Gregory compared to the Nil seed treatment (data not presented). Establishment benefits apparent in the 12 trials unfortunately did not translate into any improvement in grain yield. Rancona® Dimension did not provide a significant yield benefit over the use of no seed treatment or the two other commonly used seed treatments examined in this study under high crown rot pressure across 12 sites in 2015.

Although Rancona® Dimension is registered for the suppression of crown rot, with activity against early infection and potential establishment losses evident in this study, growers should not expect this to translate into a significant and consistent reduction in yield loss from crown rot infection when the product is used as a standalone management strategy. Integrated management remains the best strategy to reduce losses to crown rot. Growers may like to consider including Rancona® Dimension (320 mL/100 kg seed) as one additional component in their integrated management of crown rot.

• There is no evidence to support growers grading seed into different size categories and sowing the smaller seed.
• In one trial in 2015, sowing seed of different size classes did not significantly influence the yield of PBA NasmaA. Insufficient data is currently available to make a recommendation either way on this practice, but there was a trend towards reduced size of harvested seed and yield from sowing smaller PBA NasmaA seed.

• Hybrid choice and plant population had a significant impact on the yield of sorghum with irrigation. MR Buster yielded significantly higher than the other hybrids evaluated, while the higher population rates of 100,000 and 150,000 plants/ha yielded higher compared with the lower planting rates.
• The development and yield potential of the late season heads was compromised, and therefore the later developing sorghum did not take full advantage of the greater soil moisture of the intensive irrigation rate.

Conclusions

The experiment showed there are considerable productivity gains to be made by growers by selecting the right hybrid and plant population when irrigating sorghum. Irrigation management can significantly influence the growth of sorghum hybrids, affecting plant height, and grain development. Population did have an effect on yield during the trial with the higher planting populations of 100,000 & 150,000 plant/ha resulting in significantly higher yields than the 50,000 & 75,000 plants/ha. The higher plant numbers took advantage of the high plant available water from the irrigation treatments. 

Key findings:

• This site was fairly unresponsive to nitrogen (N) application. Yield and screenings did not significantly change with increasing rates of N, but there were moderate responses in grain protein to all rates of applied N in all varieties.
• The 40 kg N/ha at sowing + 40 kg N/ha in crop treatment had a significant increase in grain protein above the 40 kg N/ha at sowing only treatment in all varieties, but was not significantly different from the 80 kg N/ha at sowing treatment

Results:

There were moderate responses in grain protein to all rates of applied N in all varieties. The 40 kg N/ha at sowing + 40 kg N/ha in-crop treatment showed a significant increase in grain protein above the 40 kg N/ha at sowing only treatment in all varieties, but was not significantly different from the 80 kg N/ha at sowing treatment. Screening levels were low, with only Dart above 5% in some treatments. Dart, being the quickest variety in this trial, flowered and reached grain filling ahead of the other varieties, most likely causing it to be filling grain and losing green leaf during the hotter and drier part of September. The slower varieties probably benefited more from the late spring rains in this season

Key findings:

• This site was only moderately responsive to nitrogen (N) application. Yield and protein generally increased in all varieties with the 20 kg N/ha and 40 kg N/ha rates. However, yield decreased with higher application rates.
• Protein and screening levels increased with N rates above 40 kg N/ha.
• KioraA produced the highest screening levels. The sowing date of 5 May at Nyngan is probably a bit late for KioraA, which would have exacerbated screenings.
• Varieties with comparatively lower biomass such as DartA, LancerA, SpitfireA and SunmateA maintained higher yield and lower screening levels even with the higher N application rates with a corresponding lower impact on harvest index also observed in these varieties.

Conclusions:

Conditions at sowing were very wet. There was no effective in-crop rainfall after August and combined with temperatures above 35⁰C in September resulted in a hard finish to the season.

This site had a high background starting N level (233 kg N/ha) which was surprising given the history of continuous cropping – 17 years of crop (Wheat 40%, canola 20%, barley 20%, pulse 20%) with additional N (above starter fertiliser application) only applied once in 1999. The lower rates of 20 and 40 kg N/ha gave modest yield increases in most varieties however rates higher than this tended to reduce yield and also caused screenings levels to increase in this trial. Protein levels increased with N application rates of 40 kgN/ha and above as seed size decreased.

Biomass and harvest index data (data not shown) showed that increasing N rate in heavier strawed varieties such as EGA_Gregory, Viking, Kiora produced more dry matter with comparatively less grain yield i.e. lower harvest index.

Key mesages:

• There was a decline in yield with all rates of applied nitrogen (N), which was likely to be associated with high levels of residual soil N at the site.
• Grain protein increased with all rates of applied N in all varieties, most likely due to decreased grain size.
• Sowing time had the greatest influence on yield, with the earlier sowing time yielding close to 1 t/ha better than the later sowing time for each variety.

Conclusions:

This trial site had a high starting soil N level of 233 kg N/ha (0–120 cm) which probably contributed to declining yield with increasing rates of N application. However, protein levels still increased with increasing rates of N application, but this was most likely due to decreased grain size. Most varieties yielded almost 1 t/ha higher with TOS 1 compared with TOS 2. Sunmate and Suntop generally performed similarly at both sowing times. They were the highest yielding varieties at each sowing date, but also had lower protein achievement. Lancer and Spitfire also performed similarly at the two sowing dates and were generally lower yielding than Sunmate or Suntop at each sowing time, but obtained higher grain protein levels.

Key findings:

• Faba beans sown to target 20 plants/m2 appears to optimise yield in northern regions of NSW.
• Faba beans sown to target 30 plants/m2 appears to optimise yield in central regions of NSW.
• Faba beans sown to Doza appears more prone to frost damage than either PBA Warda or PBA Nasma get 30 plants/m2 appears to optimise yield in central regions of NSW.

Conclusions:

Limited data from the first year of trial results in 2015 suggests that for northern and western sites, 20 plants/m2 is a preferred target plant density, while in central areas 30 plants/m2 is a better option to achieve optimum yield with faba bean grown under dryland cropping conditions. Large seed does not necessarily confer higher yield, with PBA Nasma out yielding PBA Warda at only one location, Trangie, in 2015. Doza appears more prone to frost damage than either PBA Warda or PBA Nasma. Frost tolerance is a key attribute for the faba bean breeding program in northern NSW, with new releases (particularly PBA Nasma) targeted at having better tolerance than Doza, which was apparent in these trials in 2015.

• At present, there is inconsistent evidence to suggest that seed size at sowing can affect grain yield in the faba bean cultivar PBA Nasma, with a positive yield benefit associated with sowing larger seed at Trangie, but no significant yield effect at Tamworth in 2015.
• Seed size at sowing appears to be positively related to seed size at harvest.
• Further experimentation is required.
   

• 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.

• 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.
   

• 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.
   

• 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 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.
   

• 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.

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.

 

• Results from this study, clearly demonstrated that sowing timing is important. For example, delayed sowing (30 June vs 9 May) reduced the grain yield potential for EGA GregoryA by 1.75 t/ha or ~24%.
• Agronomic management factors that affected yield potential from the early sowing time (9 May) included response to nitrogen (N) input (~9% variation), with genotype and crown rot disease pressure both individually accounting for ~8% variations in grain yield.
• When the time of sowing was delayed to 30 June, agronomic factors had a larger impact/variation on grain yield potential. With both genotype (variety selection) and crown rot disease pressure responsible for a 13% variation/decline in grain yield.
• Delayed sowing also affected yield response to N with no increase in grain yield potential due to N input, whilst targeted plant population affected grain yield, with the low population treatment accounting for ~9%
   

  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.

• 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.

Key messages: 

• Richmond produced an average yield 7% higher than Soya 791 in advanced variety evaluations at early sowing dates (first week in December) over six seasons.
• Richmond produced an average yield 7.7% higher than Asgrow A6785 in advanced variety evaluations at late sowing dates (mid January) over eight seasons.
• In on-farm experiments, Richmond yielded 16% higher than Soya 791 in a wide-row system on the northern slopes, and 7% higher than Asgrow A6785 in a narrow-row coastal system.
• In addition to higher yield potential, Richmond is tolerant to lodging and pre-harvest weather damage, has clean leaf drop, large seed size and high protein, and is resistant to powdery mildew. This combination of traits provides greater crop security and a full range of market options for growers, and high quality grain for buyers and processors.

Conclusions:

The Australian soybean variety RichmondA produces large grain (22 g/100 seed) with a clear hilum and high levels of protein (42% dry matter), which is suitable for all markets including human consumption and export. The traditional variety, Asgrow A6785, has small grain (<16 g/100 seed) with a brown hilum and protein levels less than 40%, which limits the range of markets to which it is suited. The traditional variety, Soya 791, has average sized grain Agronomy (19 g/100 seed) with a light brown hilum and high levels of protein (42%). Both A6785 and Soya 791 are prone to excessive vegetative growth, especially at an early sowing date. However, this is not necessarily converted into grain yield as demonstrated in the on-farm experiment at Harwood.

RichmondA is superior to A6785 and Soya 791 in terms of grain yield, tolerance to lodging, tolerance to pre-harvest weathering and clean leaf drop. RichmondA offers a summer legume option with high yield and high grain quality for early, mid or late sowing windows in northern New South Wales. The variety’s performance was not adversely affected by the range of soil types and farming systems reported in this paper; it was superior to A6785 and Soya 791 in all situations. RichmondA is resistant to powdery mildew. This package of traits represents a significant advance in soybean varieties for the North Coast, Tablelands, Northern Slopes and Liverpool Plains production regions of northern New South Wales.

The results of the on-farm experiment of RichmondA versus Soya 791 in a wide spacing, single row system at Oakwood demonstrates the variety’s ability to compensate for wide rows and the associated lower plant populations in dryland systems. Row spacing and plant population interactions of new soybean and mungbean varieties are being investigated in the current NSW DPI–GRDC project DAN00171

 

• 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.