Wheat Lachlan Valley Condobolin

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1 Variety specific agronomy for southern irrigated cropping systems Crop Irrigation area Location Wheat Lachlan Valley Condobolin Key findings Variety choice is one of the key factors in producing high yielding irrigated wheat crops. At the target yield, variety had a significant effect on grain yield in each year but the rankings varied across experiments. Longreach Trojan A was the most consistent variety, followed by Longreach Phantom A, Espada A and LongReach Lancer A. Mid-long season varieties, with development patterns similar to Chara A and LongReach Trojan A appear to have the highest yield potential provided they are sown in early May. Corack A was very high yielding in two experiments and very poor in two others. Some new varieties performed well but will require further testing over additional seasons; these include DS Darwin A, Scepter A and Sunmate A. Nitrogen responses were generally in line with those forecast by nitrogen budgeting. Fertiliser application at sowing was at least as effective as split applications at these yield levels. Grain protein concentration varied among varieties but much of the variation could be accounted for by yield dilution. However, there was evidence of higher protein concentration in LongReach Merlin A, LongReach Spitfire A and LongReach Lancer A while EGA Gregory A, Condo A and Mace A tended to have lower grain protein concentration. Test weight and screenings levels met receival standards in almost all varieties and experiments, probably because yield levels were not high enough to cause early lodging. In the one plant population experiment, a population of 180 plants/m 2 maximised yield, producing 480 fertile heads/m 2. Introduction Irrigated wheat is an important crop in the Lachlan Valley. However, the area sown and production vary greatly depending on water availability and price, and on the likely returns compared to other crops. With reduced water allocations in recent years, many irrigators have had more land than water. These factors mean that the target yield to give the best economic return may vary widely among growers and farming systems. Target yields set by growers can range widely, from 5 t/ha to 8 t/ha, and the level of inputs is varied accordingly. Crop rotation practices have an impact and influence likely sowing time and hence the variety selected. Variety selection and agronomic practices are known to be key drivers of irrigated wheat performance but there was minimal information available for this region. The performance of current commercial varieties and management practices such as sowing rate and nitrogen regime were evaluated over three years. A yield target of 5 7 t/ha was selected based on a twoirrigation strategy, including a pre-irrigation if required.

2 Seasonal reviews In 2014, autumn rainfall was sufficient to allow early sowing (Table 1). Daytime temperatures were above average, hastening crop development and resulting in some frost damage in July and August. Rainfall was below average and temperatures above average in September and October, culminating in a 39.4 C maximum on 25 October. This caused damage even to irrigated crops. In 2015, below average May rain pushed back the first sowing opportunity to 25 May. Winter was relatively mild but high temperatures and dry conditions occurred in spring, with the warmest October on record (average maximum of 31.1 C, peak of 37.6 C). Later flowering crops suffered most from these high temperatures. In contrast, 2016 was very wet and mild, with rainfall from April to November totalling 553 mm, almost twice the long-term average. This resulted in periods of waterlogging in winter and the site was briefly inundated by floodwater after flowering. Nitrogen was undoubtedly lost through leaching and denitrification therefore yields were higher than expected given the very wet conditions. Table 1 Growing season and long-term average rainfall (mm) at Condobolin, Month Rainfall (mm) Long-term average April May June July August September October November Total Experiment site Table 2 Experiment site details, Site detail Location Condobolin, NSW Condobolin, NSW Condobolin, NSW Experiment design 1.Variety (early and late sown) 2.Variety x nitrogen 1.Variety 2.Variety x nitrogen 3. Variety x sowing rate 1.Variety 2.Variety x nitrogen Row spacing 8 rows x 22 cm 8 rows x 22 cm 8 rows x 22 cm Soil type Grey clay Grey clay Grey clay Soil nitrogen at sowing 145 kg N/ha (0 90 cm) 110 kg N/ha (0 90 cm) 70 kg N/ha (0 90 cm) Previous crop Fallow Canola Canola Sowing date (SD) SD 1: 13 May SD 2: 29 May 25 May 23 May Starter fertiliser MAP 100 kg/ha MAP 100 kg/ha MAP 100 kg/ha 2 NSW Department of Primary Industries

3 Site detail Irrigation Spring: 29 August 25 September Spring: 15 September 8 October Autumn (pre-irrigation): 15 April Treatments Up to 20 wheat varieties were evaluated each year (Table 3). A subset of quicker developing varieties was sown at a second date in Selected varieties were used in nitrogen experiments each year (tables 4 and 5) and in a plant population experiment in 2015 (Table 6). Most experiments were replicated three times except in 2016 where there were six replicates, and arranged as randomised complete blocks. Table 3 Wheat varieties evaluated in the irrigated wheat experiments at Condobolin, Chara A Chara A Beckom A Corack A Condo A Condo A Derrimut A Corack A Corack A EGA Gregory A EGA Gregory A Cutlass A Espada A Espada A DS Darwin A Kiora A Kiora A DS Pascal A Livingston A Livingston A Livingston A LongReach Cobra A LongReach Impala A LongReach LongReach Dart A LongReach Merlin A LongReach Arrow A LongReach Impala A LongReach Phantom A LongReach Cobra A LongReach Lancer A LongReach Spitfire A LongReach Kittyhawk A LongReach Phantom A LongReach Trojan A LongReach Lancer A LongReach Spitfire A LongReach Viking A LongReach Merlin A LongReach Trojan A Mace A LongReach Spitfire A Mace A Mitch A LongReach Trojan A Merinda A Shield A Mace A Sentinel A Sunmate A Scepter A Suntop A Suntop A Scout A Wallup A Sunmate A Yenda A Suntop A Table 4 Nitrogen rates and timings, Treatment no. Sowing First node Mid-elongation Ear emergence Total VARIETY SPECIFIC AGRONOMY FOR SOUTHERN IRRIGATED CROPPING SYSTEMS

4 Table 5 Nitrogen rates and timings, 2014 and Sowing First node Total 2014 (Variety) 2014 (Nitrogen rate) 2016 (Nitrogen rate) # Incorporated by sowing 1. Pre-drilled Top-dressed IBS # IBS # IBS # + top-dressed Table 6 Target plant population and average (over three varieties) sowing rates, Target population (plants/m 2 ) Average sowing rate (kg/ha) Results and discussion Appropriate measurements were taken on each experiment depending on the treatments and aims, including plant population, biomass, tiller counts, head numbers, harvest index and lodging scores. Grain yield and receival standard grain quality was recorded for grain from each plot. Variety experiments Grain yield There were significant yield responses to variety in all four experiments (Table 7). In 2014, earlier sowing (13 May) favoured the slower developing varieties (LongReach Phantom A, LongReach Cobra A, Derrimut A, Kiora A, LongReach Trojan A, Chara A, LongReach Lancer A ) which yielded near the 5 t/ha target. Varieties with this development pattern have traditionally performed well under irrigation in southern NSW. Lowest yields in the 13 May sowing date were from the quicker developing varieties including Livingston A, Merinda A and LongReach Spitfire A that likely suffered more frost damage. When sowing was delayed until 29 May, medium-quick varieties such as Espada A, and Suntop A performed well while Corack A and Wallup A yielded well at both sowing dates. The 2015 variety experiment was sown on 25 May and the highest yielding varieties were Corack A, LongReach Spitfire A and LongReach Trojan A, all close to 5 t/ha. Chara A performed poorly as did Suntop A, Condo A, and Livingston A although the latter variety probably suffered from poor seed quality and emergence. 4 NSW Department of Primary Industries

5 LongReach Trojan A was again at the top in 2016 together with new entrants DS Darwin A and Scepter A. There were some changes to the rankings in 2016: Condo A went from near bottom in 2015 to near the top, partly because of its ability to achieve a very large grain size under the favourable grain filling conditions of In contrast, the previously consistent Corack A was the lowest yielding variety. Table 7 Grain yield (t/ha) of wheat varieties in the irrigated wheat experiments at Condobolin, Variety Grain yield (t/ha) 2014 early 2014 late Beckom A 4.43 Chara A Condo A Corack A Cutlass A 4.38 Derrimut A DS Darwin A 4.78 DS Pascal A 4.26 EGA Gregory A Espada A Kiora A Livingston A LongReach Arrow A 4.18 LongReach Cobra A LongReach Dart A LongReach Impala A LongReach Kittyhawk A 4.07 LongReach Lancer A LongReach Merlin A LongReach Phantom A LongReach Spitfire A LongReach Trojan A LongReach Viking A 4.33 Mace A Merinda A Mitch A 4.55 Scepter A 4.61 LongReach Scout A Sentinel A Shield A 4.60 Sunmate A Suntop A Wallup A Yenda A F pr. < <0.001 <.001 l.s.d. (P <0.05) VARIETY SPECIFIC AGRONOMY FOR SOUTHERN IRRIGATED CROPPING SYSTEMS

6 Grain quality protein There were significant differences between varieties for grain protein concentration in all experiments (Table 8). In the early 2014 experiment, grain protein concentration averaged 9.3% suggesting that the experiment may have been nitrogen limited. LongReach Dart A, Livingston A and LongReach Spitfire A had the highest protein values and LongReach Trojan A the lowest. However, many of the protein differences were the result of protein dilution when this was taken into account, LongReach Dart A remained high and both LongReach Trojan A and EGA Gregory A were low. In the later sown experiment, average protein concentration was higher (10.8%) with LongReach Phantom A and LongReach Lancer A having above trend line proteins and Mace A having low protein. Grain protein concentrations were higher in 2015 (average 13.8%) with LongReach Merlin A and LongReach Spitfire A achieving almost 15% protein. When adjusted for yield, LongReach Merlin A and LongReach Spitfire A remained high whereas EGA Gregory A, Condo A and the soft wheat LongReach Impala A were low. The very wet conditions of 2016 resulted in low protein concentrations (average 9.1%). When adjusted for yield dilution, LongReach Merlin A, LongReach Spitfire A and LongReach Lancer A remained high whereas Cutlass A, LongReach Cobra A and LongReach Trojan A were low. Grain quality test weight and screenings Test weight and screenings were measured on all the variety experiments. While some significant differences were observed they were minor and all grain samples met receival standards. Nitrogen experiments 2014 The 2014 experiment was sown following a grassy pasture then a six-month fallow resulting in 145 kg N/ha (0 90 cm) at sowing. This is equivalent to the grain nitrogen content of a crop producing 6 t/ha grain yield at 11.5% protein. Based on previous research, about double this amount of N is needed to cover the efficiency with which soil and fertiliser nitrogen is used by the crop. In this experiment, there were significant yield responses from applying up to 120 kg N/ha of extra nitrogen and grain protein concentration also showed a yield response (Table 9). The total N supplied (145 kg N/ha soil N and 120 kg N/ha fertiliser N) met the budgeted requirement. At the optimum rate of 120 kg N/ha, apparent recovery of the applied fertiliser in the grain was 42%, in line with expectations. Irrigated wheat experiment at Condobolin, NSW Department of Primary Industries

7 Table 8 Grain protein (%) of wheat varieties in the irrigated wheat experiments at Condobolin, Variety 2014 early 2014 late Beckom A 8.8 Chara A Condo A Corack A Cutlass A 8.5 Derrimut A DS Darwin A 9.1 DS Pascal A 8.7 EGA Gregory A Espada A Kiora A Livingston A LongReach Arrow A 9.3 LongReach Cobra A 8.5 LongReach Dart A LongReach Impala A LongReach Kittyhawk A 9.2 LongReach Lancer A LongReach Merlin A LongReach Phantom A LongReach Spitfire A LongReach Trojan A LongReach Viking A 13.6 Mace A Merinda A Mitch A 13.5 Scepter A 8.8 LongReach Scout A 9.1 Sentinel A Shield A 13.9 Sunmate A Suntop A Wallup A Yenda A F pr <0.001 <0.001 l.s.d. (P <0.05) VARIETY SPECIFIC AGRONOMY FOR SOUTHERN IRRIGATED CROPPING SYSTEMS

8 Table 9 Grain yield (t/ha) and protein concentration (%) of LongReach Spitfire A at five nitrogen rates applied at sowing, N rate (kg/ha) Grain yield (t/ha) Grain protein (%) F pr. <0.001 <0.001 l.s.d. (P <0.05) The 2015 experiment was sown following a canola crop and soil testing indicated 110 kg N/ha (0 90 cm) at sowing. Three varieties of similar maturity were given three rates of nitrogen at sowing (Table 10). There were also two split treatments but there was no response to the timing of nitrogen application. There was a yield response to 60 kg N/ha and a variety interaction. LongReach Spitfire A achieved higher yield at nil fertiliser than the other varieties. Grain protein concentration ranged from 11% 15% with LongReach Spitfire A achieving higher levels when the nitrogen supplied was more than adequate for maximum yield (Table 11). The nitrogen recovered in grain was in broad agreement with calculations based on the nitrogen supplied (110 kg N/ha soil N and 60 kg N/ha fertiliser N). Table Grain yield (t/ha) response of three wheat varieties to nitrogen fertiliser applied at sowing, Variety Nitrogen fertiliser (kg/ha) Variety mean Livingston A LongReach Spitfire A Sunmate A Fertiliser mean Nitrogen Var x N F pr. < l.s.d. (P <0.05) Table 11 Grain protein (%) response of three wheat varieties to nitrogen fertiliser applied at sowing, Variety Nitrogen fertiliser (kg/ha) Variety mean Livingston A LongReach Spitfire A Sunmate A Fertiliser mean Nitrogen Var x N F pr. < l.s.d. (P <0.05) NSW Department of Primary Industries

9 2016 Soil nitrogen at sowing in 2016 (70 kg N/ha (0 90 cm)) was quite low following wheat and canola crops. Periods of waterlogging in the winter and spring would also have reduced the supply of nitrogen. Consequently, there were large yield responses to applying up to 120 kg N/ha by Sunmate A and Condo A (Figure 1). The other two varieties appeared to suffer more from the wet conditions and showed less response to applied nitrogen. A split application (sowing and Z30) at the highest rate was inferior to the equivalent N rate applied in one application at sowing. There were significant responses to fertiliser, variety and their interaction for grain protein concentration (Figure 2). LongReach Merlin A and LongReach Spitfire A achieved high grain protein levels but this was largely due to their lower yield. There were no variety differences in grain nitrogen uptake. Apparent recovery of fertiliser nitrogen was low in 2016, only 24% at the optimum rate, indicating nitrogen losses occurred under the waterlogged conditions. 7 6 Grain yield (t/ha) Nitrogen applied (kg/ha) Condo Merlin Spitfire Sunmate Figure 1 Grain yield (t/ha) response of four wheat varieties to nitrogen applied at sowing at Condobolin, The variety by nitrogen response was significant (F pr. <0.001, l.s.d. (P <0.05) = 0.54 t/ha) Grain protein (%) Condo 7 Merlin Spitfire 6 Sunmate Nitrogen applied Figure 2 Grain protein (%) response of four wheat varieties to nitrogen applied at sowing at Condobolin, The variety by nitrogen response was significant (F pr. <0.018, l.s.d. (P <0.05) = 0.58%). VARIETY SPECIFIC AGRONOMY FOR SOUTHERN IRRIGATED CROPPING SYSTEMS

10 The irrigated wheat experiments at Condobolin inundated with water on 18 October Plant population A plant population experiment was conducted in 2015 with three varieties and four target plant populations. Poor vigour in the seed of one variety (Livingston A ) resulted in much lower plant establishment (Figure 3). The other two varieties (LongReach Spitfire A and Sunmate A ) performed similarly and so their mean performance is presented in Table 12. Establishment decreased from 94% to 83% as sowing rate increased resulting in a range of plants/m 2. Grain yield was maximised (4.7 t/ha) from a population of 180 plants/m 2 which resulted in 480 fertile ears/m 2. Table 12 Plant population, grain yield, fertile ears and harvest index from four plant populations, averaged over two varieties (LongReach Spitfire A and Sunmate A ) at Condobolin, Target plant population (plants/m 2 ) Actual plant population (plants/m 2 ) Grain yield (t/ha) Fertile ears (ears/m 2 ) Harvest index F pr. <0.001 <0.001 <0.001 n.s. l.s.d. (P <0.05) The yield response to plant population for each of the varieties is shown in Figure 3. The yield of Livingston A was constrained by poor seedling vigour as well as by low plant populations. 10 NSW Department of Primary Industries

11 6.0 Grain yield (t/ha) Livingston Spitfire Sunmate Plant population (plants/m 2 ) Figure 3 Grain yield response to plant population for three wheat varieties at Condobolin, The variety by seeding rate response was significant (F pr. <0.015, l.s.d. (P <0.05) = 0.42 t/ha). Summary The project Growing conditions and sowing time varied across the experiments which influenced the results. Earlier sowing in 2014 favoured the mid-long season varieties despite the hot spring, although quick developing varieties in the late sowing experiment also performed well. There appeared to be differing varietal responses to the waterlogging conditions of This resulted in major changes in varietal yield ranking among experiments. LongReach Trojan A was the most consistent variety followed by LongReach Phantom A, Espada A and LongReach Lancer A. New varieties were included in the experiments as they became available and some, including DS Darwin A, Scepter A and Sunmate A, performed well but require more years of testing. Much of the grain protein concentration variation between varieties could be accounted for by yield dilution. However, LongReach Merlin A, LongReach Spitfire A and LongReach Lancer A tended to achieve higher levels while EGA Gregory A, Condo A and Mace A tended to produce lower grain protein levels. There were few instances of varieties differing significantly for other receival standards including test weight and screenings, probably because yield levels were not high enough to cause early lodging. Soil nitrogen levels at sowing varied from kg N/ha. Nitrogen responses reflected these differences and were generally in line with those forecast by nitrogen budgeting. Fertiliser application at sowing was generally at least as effective as split applications at these yield levels. In the one plant population experiment conducted, a population of 180 plants/m 2 maximised yield producing 480 fertile heads/m 2. This variety specific agronomy package (VSAP) is an output of the Southern irrigated cereal and canola varieties achieving target yields project (DAN00198; ). It summarises the research outcomes from experiments that were conducted in this research node on this crop type. The objective of the project was to demonstrate an increase in irrigated cereal and canola production, and ultimately water use efficiency, through improvement of grower and adviser knowledge of high yielding cereal and canola varieties and specific agronomy management that will increase production and improve profitability under irrigation. VARIETY SPECIFIC AGRONOMY FOR SOUTHERN IRRIGATED CROPPING SYSTEMS

12 The project area extended from the Lachlan Valley in NSW to Victoria, Tasmania and across to south-eastern South Australia. The project comprised a series of research experiments to identify the optimum cereal and canola varieties and agronomic management practices for irrigated cereal and canola production in south-eastern Australia. Specific research questions were tailored to the geographic area, or research node. Organisations that have contributed to the project by conducting research experiments and the location of their research node are NSW DPI (Murrumbidgee Valley, NSW; Murray Valley, NSW), Victorian Irrigated Cropping Council (Northern Victoria), Southern Farming Systems (Tasmania), MacKillop Farm Management Group (south-east South Australia), Central West Farming Systems (Lachlan Valley, NSW) and AgGrow Agronomy & Research (Lachlan Valley, NSW). In addition to the VSAPs, the project also produced an irrigated wheat production manual and an irrigated canola production manual (available by contacting the author) and an extensive database of experiment results. The project has joint investment by NSW Department of Primary Industries (NSW DPI) and the Grains Research and Development Corporation (GRDC). Acknowledgements This research is part of the Southern irrigated cereal and canola varieties achieving target yields project (DAN00198; ) which has joint investment by NSW Department of Primary Industries (NSW DPI) and the Grains Research and Development Corporation (GRDC). Central West Farming Systems would like to acknowledge the contributions of their field staff throughout this research project. Further information Dr Neil Fettell Central West Farming Systems neil.fettell@une.edu.au ISBN: State of New South Wales through Department of Industry You may copy, distribute, display, download and otherwise freely deal with this publication for any purpose, provided that you attribute the Department of Industry as the owner. However, you must obtain permission if you wish to: charge others for access to the publication (other than at cost) include the publication in advertising or a product for sale modify the publication republish the publication on a website. You may freely link to the publication on a departmental website. Disclaimer The information contained in this publication is based on knowledge and understanding at the time of writing (June 2017) and may not be accurate, current or complete. The State of New South Wales (including the NSW Department of Industry), the author and the publisher take no responsibility, and will accept no liability, for the accuracy, currency, reliability or correctness of any information included in the document (including material provided by third parties). Readers should make their own inquiries and rely on their own advice when making decisions related to material contained in this publication. Always read the label Users of agricultural or veterinary chemical products must always read the label and any permit, before using the product, and strictly comply with the directions on the label and the conditions of any permit. Users are not absolved from compliance with the directions on the label or the conditions of the permit by reason of any statement made or not made in this publication. The product trade names in this publication are supplied on the understanding that no preference between equivalent products is intended and that the inclusion of a product name does not imply endorsement by the department over any equivalent product from another manufacturer