Journal articles on the topic 'Australian grain crops'
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1
Holloway, Joanne C., Michael J. Furlong, and Philip I. Bowden. "Management of beneficial invertebrates and their potential role in integrated pest management for Australian grain systems." Australian Journal of Experimental Agriculture 48, no. 12 (2008): 1531. http://dx.doi.org/10.1071/ea07424.
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Beneficial invertebrates (predators and parasitoids) can make significant contributions to the suppression of insect pest populations in many cropping systems. In Australia, natural enemies are incorporated into integrated pest management programs in cotton and horticultural agroecosystems. They are also often key components of effective programs for the management of insect pests of grain crops in other parts of the world. However, few studies have examined the contribution of endemic natural enemies to insect pest suppression in the diverse grain agroecosystems of Australia. The potential of these organisms is assessed by reviewing the role that natural enemies play in the suppression of the major pests of Australian grain crops when they occur in overseas grain systems or other local agroecosystems. The principal methods by which the efficacy of biological control agents may be enhanced are examined and possible methods to determine the impact of natural enemies on key insect pest species are described. The financial and environmental benefits of practices that encourage the establishment and improve the efficacy of natural enemies are considered and the constraints to adoption of these practices by the Australian grains industry are discussed.
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Anderson, WK, GB Crosbie, and K. Lemsom. "Production practices for high protein, hard wheat in Western Australia." Australian Journal of Experimental Agriculture 35, no. 5 (1995): 589. http://dx.doi.org/10.1071/ea9950589.
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Field experiments were conducted at 18 sites over 4 years in the eastern and north-eastern wheatbelt of Western Australia where average annual rainfall is <400mm, to investigate suitable techniques for the production of high protein (>13%) wheat in an area that traditionally produces grain of a much lower average protein percentage. Wilgoyne yielded as well as, or better than, any of the cultivars accepted into the Special Hard (SH) grade in Western Australia but 5-10% less than cultivars suitable for the Australian Standard White (ASW) grade. Differences between cultivars were greatest at the optimum sowing time in late May. Lower yields in early May were attributed to water stress during early growth or to frost damage during grain filling. The addition of nitrogen (N) fertiliser to crops sown after 1 June was less effective in increasing grain yield and grain protein than N added to earlier sowings. Most crops that produced >13% protein followed medic or field peas. The addition of N fertiliser was seldom required to produce this concentration of protein in crops that followed medic or peas. Crops following pasture with a low legume content or wheat had lower grain protein concentrations. Friable red-brown earth soils in a medic or pea rotation were able to achieve the required grain protein, but other combinations were not extensively tested. From these experiments, cultivars with inherently small grains due to their propensity to produce high levels of small grain screenings (whole grain through a 2-mm, slotted sieve) may be less able to increase yields economically by increasing kernel numbers per unit area under conditions in Western Australia.
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Brier, H. B., D. A. H. Murray, L. J. Wilson, A. H. Nicholas, M. M. Miles, P. R. Grundy, and A. J. McLennan. "An overview of integrated pest management (IPM) in north-eastern Australian grain farming systems: past, present and future prospects." Australian Journal of Experimental Agriculture 48, no. 12 (2008): 1574. http://dx.doi.org/10.1071/ea08166.
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The authors overview integrated pest management (IPM) in grain crops in north-eastern Australia, which is defined as the area north of latitude 32°S. Major grain crops in this region include the coarse grains (winter and summer cereals), oilseeds and pulses. IPM in these systems is complicated by the diversity of crops, pests, market requirements and cropping environments. In general, the pulse crops are at greatest risk, followed by oilseeds and then by cereal grains. Insecticides remain a key grain pest management tool in north-eastern Australia. IPM in grain crops has benefited considerably through the increased adoption of new, more selective insecticides and biopesticides for many caterpillar pests, in particular Helicoverpa spp. and loopers, and the identification of pest–crop scenarios where spraying is unnecessary (e.g. for most Creontiades spp. populations in soybeans). This has favoured the conservation of natural enemies in north-eastern Australia grain crops, and has arguably assisted in the management of silverleaf whitefly in soybeans in coastal Queensland. However, control of sucking pests and podborers such as Maruca vitrata remains a major challenge for IPM in summer pulses. Because these crops have very low pest-damage tolerances and thresholds, intervention with disruptive insecticides is frequently required, particularly during podfill. The threat posed by silverleaf whitefly demands ongoing multi-pest IPM research, development and extension as this pest can flare under favourable seasonal conditions, especially where disruptive insecticides are used injudiciously. The strong links between researchers and industry have facilitated the adoption of IPM practices in north-eastern Australia and augers well for future pest challenges and for the development and promotion of new and improved IPM tactics.
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McDonald, GK. "The contribution of nitrogen fertiliser to the nitrogen nutrition of rainfed wheat crops in Australia: a review." Australian Journal of Experimental Agriculture 29, no. 3 (1989): 455. http://dx.doi.org/10.1071/ea9890455.
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Very little nitrogen (N) fertiliser is applied to wheat crops in Australia. Currently, about 105 t of N fertiliser (less than 20% of Australia's total consumption) are used annually at an average rate of 2-3 kg Nha. This scant use of N fertiliser over much of the Australian wheat belt N is because the N derived from a legume-dominant pasture ley is thought to provide a wheat crop's N requirement. However, trends in the grain protein content of Australian wheat and some other indices of soil fertility suggest that legume-based pastures have not always been able to supply all the N required for adequate nutrition of the wheat crop and that there has been some occasional need for extra N from applications of fertiliser. Recent declines in the productivity and quality of pastures has further increased the need for supplementary applications of N fertiliser. The increase in grain legume production also has been partly based on the presumption that grain legumes contribute to the N economy of the following wheat crop. Many experiments throughout the wheat belt show a yield advantage of wheat grown after a grain legume, but these rotation trials also show that the level of productivity of the grain legume has little effect on the yield of the following wheat crop. A review of these experiments suggests that grain legumes, directly, contribute little to the N nutrition of a following wheat crop and their benefit may be from the legume acting as a disease break or providing the opportunity to control grassy weeds.
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Edwards, Owain R., Bernie Franzmann, Deborah Thackray, and Svetlana Micic. "Insecticide resistance and implications for future aphid management in Australian grains and pastures: a review." Australian Journal of Experimental Agriculture 48, no. 12 (2008): 1523. http://dx.doi.org/10.1071/ea07426.
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Aphids can cause substantial damage to cereals, oilseeds and legumes through direct feeding and through the transmission of plant pathogenic viruses. Aphid-resistant varieties are only available for a limited number of crops. In Australia, growers often use prophylactic sprays to control aphids, but this strategy can lead to non-target effects and the development of insecticide resistance. Insecticide resistance is a problem in one aphid pest of Australian grains in Australia, the green peach aphid (Myzus persicae). Molecular analyses of field-collected samples demonstrate that amplified E4 esterase resistance to organophosphate insecticides is widespread in Australian grains across Australia. Knockdown resistance to pyrethroids is less abundant, but has an increased frequency in areas with known frequent use of these insecticides. Modified acetylcholinesterase resistance to dimethyl carbamates, such as pirimicarb, has not been found in Australia, nor has resistance to imidacloprid. Australian grain growers should consider control options that are less likely to promote insecticide resistance, and have reduced impacts on natural enemies. Research is ongoing in Australia and overseas to provide new strategies for aphid management in the future.
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Lawrence, Louise. "Host Plant Resistance and IPM in Australian Grain Crops." Outlooks on Pest Management 20, no. 2 (April 1, 2009): 74–76. http://dx.doi.org/10.1564/20apr08.
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Sadras, Victor O., and John F. Angus. "Benchmarking water-use efficiency of rainfed wheat in dry environments." Australian Journal of Agricultural Research 57, no. 8 (2006): 847. http://dx.doi.org/10.1071/ar05359.
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Attainable water-use efficiency relates attainable yield, i.e. the best yield achieved through skilful use of available technology, and seasonal evapotranspiration (ET). For wheat crops in south-eastern Australia, there is a common, often large gap between actual and attainable water-use efficiency. To evaluate whether this gap is only an Australian problem or a general feature of dry environments, we compared water-use efficiency of rainfed wheat in south-eastern Australia, the North American Great Plains, China Loess Plateau, and the Mediterranean Basin. A dataset of published data was compiled (n = 691); water-use efficiency (WUEY/ET) was calculated as the ratio between actual grain yield and seasonal ET. Maximum WUEY/ET was 22 kg grain/ha.mm. Average WUEY/ET (kg grain/ha.mm) was 9.9 for south-eastern Australia, 9.8 for the China Loess Plateau, 8.9 for the northern Great Plains of North America, 7.6 for the Mediterranean Basin, and 5.3 for the southern-central Great Plains; the variation in average WUEY/ET was largely accounted for by reference evapotranspiration around flowering. Despite substantial differences in important factors including soils, precipitation patterns, and management practices, crops in all these environments had similarly low average WUEY/ET, between 32 and 44% of attainable efficiency. We conclude that low water-use efficiency of Australian crops is not a local problem, but a widespread feature of dry environments. Yield gap analysis for crops in the Mallee region of Australia revealed low availability of phosphorus, late sowing, and subsoil chemical constraints as key factors reducing water-use efficiency, largely through their effects on soil evaporation.
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Tran, S. T., and T. K. Smith. "A survey of free and conjugated deoxynivalenol in the 2009, 2010 and 2011 cereal crops in Australia." Animal Production Science 53, no. 5 (2013): 407. http://dx.doi.org/10.1071/an12081.
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Free and conjugated deoxynivalenol (DON, vomitoxin) were determined in samples of cereal grain collected from the 2009, 2010 and 2011 crops in the Australian states of New South Wales, Queensland, South Australia, Victoria and Western Australia. Free DON was absent in 53–64% of analysed samples. Levels of free DON ranged from 0.10 to 7.31 µg/g. The highest levels of free DON were found in samples collected from the New South Wales 2010 crop while no samples from South Australia or Western Australia regions contained this compound. Free DON in the samples collected from the 2010 crop was significantly higher compared with those from the 2009 and the 2011 crop. Conjugated DON was detected in 61, 87 and 68% of contaminated grain samples in the 2009, 2010 and 2011 crop, respectively. Conjugated DON was found mainly in the samples collected from the 2009 crop (up to 48%) and the 2011 crop (up to 43%) but no significant difference between free DON and total DON content was observed. The current survey emphasises the frequency of non-detectable, conjugated DON in Australian cereal crops and the potential challenges in understanding the hazard posed by DON-contaminated feedstuffs.
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Lawrence, Louise. "The Future for Aphids in Australian Grain Crops and Pastures." Outlooks on Pest Management 20, no. 6 (December 1, 2009): 285–88. http://dx.doi.org/10.1564/20dec11.
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Murray, David A. H., Michael B. Clarke, and David A. Ronning. "Estimating invertebrate pest losses in six major Australian grain crops." Australian Journal of Entomology 52, no. 3 (January 15, 2013): 227–41. http://dx.doi.org/10.1111/aen.12017.
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Owen, Mechelle J., Roslyn K. Owen, and Stephen B. Powles. "A Survey in the Southern Grain Belt of Western Australia Did Not Find Conyza Spp. Resistant to Glyphosate." Weed Technology 23, no. 3 (September 2009): 492–94. http://dx.doi.org/10.1614/wt-08-166.1.
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Glyphosate-resistant crops will be grown for the first time in Western Australia in 2009. A survey was conducted across 150,000 km2 of the southeastern part of the Western Australian grain belt in 2007 to determine whether glyphosate-resistant Conyza populations were present. Sixty-eight Conyza populations were collected from various fields and roadside locations. These populations were collected from areas where Conyza was known to exist. Populations were screened with glyphosate and all populations were found to be glyphosate-susceptible. While no glyphosate-resistant Conyza populations were found in the southeastern grain belt of Western Australia, it provides baseline data prior to the introduction of glyphosate-resistant crops in this region. It is important to monitor the efficacy of glyphosate as resistance becomes more prevalent in weeds of various cropping systems worldwide.
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Ahmad-Hamdani, M. S., Mechelle J. Owen, Qin Yu, and Stephen B. Powles. "ACCase-Inhibiting Herbicide-ResistantAvenaspp. Populations from the Western Australian Grain Belt." Weed Technology 26, no. 1 (March 2012): 130–36. http://dx.doi.org/10.1614/wt-d-11-00089.1.
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Avenaspp. are world weeds with many cases of evolved herbicide resistance. In Australia,Avenaspp. (wild oat and sterile oat) are a major problem, especially in grain crops. Acetyl-CoA carboxylase (ACCase)–inhibiting herbicides have been used extensively since the late 1970s forAvenaspp. control. However, continued reliance on these herbicides has resulted in the evolution of resistantAvenaspp. populations. Resistance across many ACCase-inhibiting herbicides was characterized in fourAvenaspp. populations from the Western Australian grain belt. Dose–response experiments were conducted to determine the level of resistance to the aryloxyphenoxypropionates and cyclohexanediones and to the phenylpyrazoline herbicide pinoxaden. On the basis of resistance index values, all four resistant populations exhibited high-level diclofop resistance but varied in the level of resistance to other ACCase-inhibiting herbicides tested. It is evident thatAvenaspp. populations from the Western Australian grain belt have evolved resistance to a number of ACCase-inhibiting herbicides.
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Mielenz, Henrike, Peter J. Thorburn, Robert H. Harris, Sally J. Officer, Guangdi Li, Graeme D. Schwenke, and Peter R. Grace. "Nitrous oxide emissions from grain production systems across a wide range of environmental conditions in eastern Australia." Soil Research 54, no. 5 (2016): 659. http://dx.doi.org/10.1071/sr15376.
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Nitrous oxide (N2O) emissions from Australian grain cropping systems are highly variable due to the large variations in soil and climate conditions and management practices under which crops are grown. Agricultural soils contribute 55% of national N2O emissions, and therefore mitigation of these emissions is important. In the present study, we explored N2O emissions, yield and emissions intensity in a range of management practices in grain crops across eastern Australia with the Agricultural Production Systems sIMulator (APSIM). The model was initially evaluated against experiments conducted at six field sites across major grain-growing regions in eastern Australia. Measured yields for all crops used in the experiments (wheat, barley, sorghum, maize, cotton, canola and chickpea) and seasonal N2O emissions were satisfactorily predicted with R2=0.93 and R2=0.91 respectively. As expected, N2O emissions and emissions intensity increased with increasing nitrogen (N) fertiliser input, whereas crop yields increased until a yield plateau was reached at a site- and crop-specific N rate. The mitigation potential of splitting N fertiliser application depended on the climate conditions and was found to be relevant only in the southern grain-growing region, where most rainfall occurs during the cropping season. Growing grain legumes in rotation with cereal crops has great potential to reduce mineral N fertiliser requirements and so N2O emissions. In general, N management strategies that maximise yields and increase N use efficiency showed the greatest promise for N2O mitigation.
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Simmons, Aaron T., Alexandra Murray, Philippa M. Brock, Timothy Grant, Annette L. Cowie, Sandra Eady, and Bharat Sharma. "Life cycle inventories for the Australian grains sector." Crop and Pasture Science 70, no. 7 (2019): 575. http://dx.doi.org/10.1071/cp18412.
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Grain production is a key source of food globally and is an important agricultural system for the Australian economy. Environmental impacts such as the emissions of greenhouse gases (GHG) associated with grain production are well documented and the Australian grains industry has strived to ensure ongoing improvement. To facilitate this improvement, the industry funded the development of life cycle inventories to provide broad geographical coverage. Cradle-to-gate inventories for wheat were developed for each of the grains industry agro-ecological zones, and inventories were developed for minor cereal crops (e.g. barley, sorghum), oilseeds (i.e. canola) and legumes where relevant. Data for inventory development were taken from numerous sources and validated by using data collected through interviews with experts in each agro-ecological zone. Inventory data were also collected so that indicators in addition to global-warming impacts could be assessed. Global warming impacts for wheat production ranged from 193 to 567 kg carbon dioxide equivalents (CO2-e) t–1, and global warming impacts were 597–851, 333–361, 169–285 and 74–672 kg CO2-e t–1 for canola, sorghum, barley and grain-legume production, respectively. Results for eutrophication, freshwater ecotoxicity, land-use and abiotic depletion (fossil-fuel use) are also presented.
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FitzGerald, RD, ML Curll, and EW Heap. "Wheat for fodder and grain on the Northern Tablelands of New South Wales." Australian Journal of Experimental Agriculture 35, no. 1 (1995): 93. http://dx.doi.org/10.1071/ea9950093.
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Thirty varieties of wheat originating from Australia, UK, USA, Ukraine, and France were evaluated over 3 years as dual-purpose wheats for the high rainfall environment of the Northern Tablelands of New South Wales (mean annual rainfall 851 mm). Mean grain yields (1.9-4.3 t/ha) compared favourably with record yields in the traditional Australian wheatbelt, but were much poorer than average yields of 6.5 t/ha reported for UK crops. A 6-week delay in sowing time halved grain yield in 1983; cutting in spring reduced yield by 40% in 1986. Grazing during winter did not significantly reduce yields. Results indicate that the development of wheat varieties adapted to the higher rainfall tablelands and suited to Australian marketing requirements might help to provide a useful alternative enterprise for tableland livestock producers.
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Selle, Peter H., Bernard V. McInerney, Leon R. McQuade, Ali Khoddami, Peter V. Chrystal, Robert J. Hughes, and Sonia Yun Liu. "Composition and characterisation of kafirin, the dominant protein fraction in grain sorghum." Animal Production Science 60, no. 9 (2020): 1163. http://dx.doi.org/10.1071/an19393.
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Context Sorghum is an important feed grain for chicken-meat production in Australia. However, it is usually considered inferior to wheat – the foremost feed grain. Kafirin, the dominant protein fraction in sorghum, may be a major contributor to this inferiority due to its negative influence on starch digestion and energy utilisation. Aims The objective of this study was to determine kafirin concentrations in sorghum relative to crude protein and amino acid profiles of both kafirin and total sorghum protein. Methods Concentrations of amino acids and kafirin in 19 Premium Grains for Livestock Program sorghum varieties were quantified. These data were combined with that of up to 14 Poultry Research Foundation sorghum varieties to generate the most exhaustive documentation of its kind. The methodology developed to quantify kafirin concentrations in sorghum is thoroughly described. In addition, essential amino acid profiles in 25 grain sorghums from Australian surveys completed in 1998, 2009 and 2016 were compared statistically. Also, consideration was given to relevant near-infrared spectroscopy predicted data from 992 sorghum varieties from 2014 to 2019. Key results The average kafirin concentration of 48.2 g/kg represented 51.9% of the 92.9 g/kg crude protein (N × 5.81) content in 33 varieties grain sorghum. Kafirin holds a substantial 62.7% share of leucine as the concentration was 8.53 g/kg in kafirin as opposed 13.73 g/kg in total sorghum protein. The proposal was advanced that kafirin contents of local sorghum crops have increased during the past two decades from the 1998, 2009 and 2016 surveys of amino acid profiles in grain sorghum. Conclusions Kafirin concentrations in Australian sorghum crops may have increased over the past two decades, which may be having a negative impact on the performance of broiler chickens offered sorghum-based diets. Implications Breeding programs should be directed towards sorghums with lesser kafirin proportions of sorghum protein and/or modified kafirin protein bodies to enhance the nutritive value of sorghum as a feed grain for chicken-meat production.
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Allen, H. M., J. K. Pumpa, and G. D. Batten. "Effect of frost on the quality of samples of Janz wheat." Australian Journal of Experimental Agriculture 41, no. 5 (2001): 641. http://dx.doi.org/10.1071/ea00187.
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The effect of frost damage on wheat grain quality was examined in samples of an Australian Prime Hard wheat cultivar Janz. Wheat grain samples that were lightly frosted, severely frosted and unfrosted were obtained from the Riverina district of New South Wales. Each frosted sample was separated by sieving into 2 fractions by size using a commercial grader that was equipped with an aspirator. As the degree of frost damage in the samples increased, grain size decreased, flour extraction decreased, flour ash increased, flour colour deteriorated, dough strength decreased, baking quality decreased, α-amylase activity increased and falling number decreased. Quality assessment of the separated grain fractions showed that the large grains (>2 mm) in both lightly frosted and severely frosted crops were equal or better than the unfrosted sample in all tested quality parameters. The large grain fraction fully met the Australian Prime Hard receival standards and was of quality commensurate with the grade. Separation of grain by size was calculated to be commercially viable for up to 50% frost damage. A commercial flourmill purchased frosted feed grain, followed the sieving procedure, and produced large grain consistent with unfrosted wheat that was subsequently used for normal processing.
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Ward, Samantha E., Paul A. Umina, Sarina Macfadyen, and Ary A. Hoffmann. "Hymenopteran Parasitoids of Aphid Pests within Australian Grain Production Landscapes." Insects 12, no. 1 (January 8, 2021): 44. http://dx.doi.org/10.3390/insects12010044.
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In grain crops, aphids are important pests, but they can be suppressed by hymenopteran parasitoids. A challenge in incorporating parasitoids into Integrated Pest Management (IPM) programs, however, is that parasitoid numbers can be low during periods within the season when aphids are most damaging. Understanding the population dynamics of key aphid species and their parasitoids is central to ameliorating this problem. To examine the composition and seasonal trends of both aphid and parasitoid populations in south-eastern Australia, samples were taken throughout the winter growing seasons of 2017 and 2018 in 28 fields of wheat and canola. Myzus persicae (Sulzer) was the most abundant aphid species, particularly within canola crops. Across all fields, aphid populations remained relatively low during the early stages of crop growth and increased as the season progressed. Seasonal patterns were consistent across sites, due to climate, crop growth stage, and interactions between these factors. For canola, field edges did not appear to act as reservoirs for either aphids or parasitoids, as there was little overlap in the community composition of either, but for wheat there was much similarity. This is likely due to the presence of similar host plants within field edges and the neighbouring crop, enabling the same aphid species to persist within both areas. Diaeretiella rapae (M’Intosh) was the most common parasitoid across our study, particularly in canola, yet was present only in low abundance at field edges. The most common parasitoid in wheat fields was Aphidius matricariae (Haliday), with field edges likely acting as a reservoir for this species. Secondary parasitoid numbers were consistently low across our study. Differences in parasitoid species composition are discussed in relation to crop type, inter-field variation, and aphid host. The results highlight potential focal management areas and parasitoids that could help control aphid pests within grain crops.
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Ward, Samantha E., Paul A. Umina, Sarina Macfadyen, and Ary A. Hoffmann. "Hymenopteran Parasitoids of Aphid Pests within Australian Grain Production Landscapes." Insects 12, no. 1 (January 8, 2021): 44. http://dx.doi.org/10.3390/insects12010044.
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In grain crops, aphids are important pests, but they can be suppressed by hymenopteran parasitoids. A challenge in incorporating parasitoids into Integrated Pest Management (IPM) programs, however, is that parasitoid numbers can be low during periods within the season when aphids are most damaging. Understanding the population dynamics of key aphid species and their parasitoids is central to ameliorating this problem. To examine the composition and seasonal trends of both aphid and parasitoid populations in south-eastern Australia, samples were taken throughout the winter growing seasons of 2017 and 2018 in 28 fields of wheat and canola. Myzus persicae (Sulzer) was the most abundant aphid species, particularly within canola crops. Across all fields, aphid populations remained relatively low during the early stages of crop growth and increased as the season progressed. Seasonal patterns were consistent across sites, due to climate, crop growth stage, and interactions between these factors. For canola, field edges did not appear to act as reservoirs for either aphids or parasitoids, as there was little overlap in the community composition of either, but for wheat there was much similarity. This is likely due to the presence of similar host plants within field edges and the neighbouring crop, enabling the same aphid species to persist within both areas. Diaeretiella rapae (M’Intosh) was the most common parasitoid across our study, particularly in canola, yet was present only in low abundance at field edges. The most common parasitoid in wheat fields was Aphidius matricariae (Haliday), with field edges likely acting as a reservoir for this species. Secondary parasitoid numbers were consistently low across our study. Differences in parasitoid species composition are discussed in relation to crop type, inter-field variation, and aphid host. The results highlight potential focal management areas and parasitoids that could help control aphid pests within grain crops.
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Malik, Raj S., Mark Seymour, Robert J. French, John A. Kirkegaard, Roger A. Lawes, and Mark A. Liebig. "Dynamic crop sequencing in Western Australian cropping systems." Crop and Pasture Science 66, no. 6 (2015): 594. http://dx.doi.org/10.1071/cp14097.
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During the last two decades in Western Australia, the traditional mixed farming system has been increasingly displaced by intensive crop sequences dominated by wheat. Intensive wheat sequences are usually maintained by using suitable breaks, including pasture, fallow, or alternative cereal, oilseed and legume crops, to control weeds and disease, or maintain the supply of nitrogen to crops. New cereal fungicide options may also assist to maintain intensive cereal systems by suppressing soilborne cereal diseases. To guide the successful diversification of intensive cereal systems, we evaluated the effect of a 2-year experimental matrix of 10 different sequence options. Wheat in the sequence was treated with the fluquinconazole fungicide Jockey (wheat + J) to control soilborne pathogens, or with the usual seed dressing of flutriafol fungicide (wheat – J), used for control of bunts and smuts only. The sequences were wheat + J, wheat – J, barley, grain oats, oaten hay, canola, lupin, field pea, oat–vetch green manure, bare fallow) in which all treatment combinations were grown in year 2 following the same 10 treatments in year 1. In year 3, wheat + J was grown across the entire area as the test crop. In year 2, grain yields of all crops were reduced when crops were grown on their own residues, including wheat (22% reduction), canola (46%), lupin (40%) and field pea (51%). Wheat + J significantly outyielded wheat – J by 300 kg ha–1 in year 1 (14% increase) and 535 kg ha–1 in year 2 (26% increase). Wheat + J was more responsive to break crops than wheat – J in both year 1 and year 2. Break crops sown in year 1, such as canola, fallow, field pea, lupin and oaten hay, continued to have a positive effect on year 3 wheat + J yields. This study has highlighted the importance of break crops to following cereal crops, and provided an example in which a seed-dressing fungicide fluquinconazole in the presence of low levels of disease consistently improved wheat yields.
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Speirs, Simon D., Doug J. Reuter, Ken I. Peverill, and Ross F. Brennan. "Making Better Fertiliser Decisions for Cropping Systems in Australia: an overview." Crop and Pasture Science 64, no. 5 (2013): 417. http://dx.doi.org/10.1071/cp13034.
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Australian grain production depends on applied fertiliser, particularly nitrogen (N) and phosphorus (P), and to a lesser extent potassium (K) and sulfur (S). Despite this dependence, soil testing is used sparingly as a tool to underpin fertiliser decisions. Some grain producers typically conduct soil tests at least once every 3 years on a selection of individual fields, but it is broadly understood that many grain producers use soil testing rarely or not at all. The choice by many grain producers not to support fertiliser decisions by soil testing relates to several factors. One key factor has been a perception that soil test interpretation criteria, previously published separately before collation by K. I. Peverill, L. A. Sparrow, and D. J. Reuter, may be biased or unreliable. The current paper provides an overview of research findings, presented in this special edition of Crop & Pasture Science, describing a national approach to the collation of all available and statistically valid N, P, K, and S response trials for cereal, oilseed, and pulse crops in Australia. It provides an overview of the process adopted to make this single national dataset available to both the grains and fertiliser industries. The process to build adoption has formed an integral component of the approach, as calibration data derived from the national database are being used to underpin soil test interpretation as part of fertiliser recommendations made through Fertcare to grain producers in Australia.
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Bell, Lindsay W., Richard G. Bennett, Megan H. Ryan, and Heather Clarke. "The potential of herbaceous native Australian legumes as grain crops: a review." Renewable Agriculture and Food Systems 26, no. 1 (August 18, 2010): 72–91. http://dx.doi.org/10.1017/s1742170510000347.
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AbstractMany agricultural systems around the world are challenged by declining soil resources, a dry climate and increases in input costs. The cultivation of plants that are better adapted than current crop species to nutrient poor soils, a dry climate and low-input agricultural systems would aid the continued profitability and environmental sustainability of agricultural systems. This paper examines herbaceous native Australian legumes for their capacity to be developed as grain crops adapted to dry environments. The 14 genera that contain herbaceous species areCanavalia, Crotalaria, Cullen, Desmodium, Glycine, Glycyrrhiza, Hardenbergia, Indigofera, Kennedia, Lotus, Rhynchosia, Swainsona, TrigonellaandVigna. A number of these genera (e.g.,Glycine, Crotalaria, TrigonellaandVigna) include already cultivated exotic grain legumes. Species were evaluated based on the extent to which their natural distribution corresponded to arid and semi-arid climatic regions, as well as the existing information on traits related to harvestability (uniformity of ripening, propensity to retain pod, pod shattering and growth habit), grain qualities (seed size, chemistry, color and the absence of toxins) and fecundity. Published data on seed yield were rare, and for many other traits information was limited. The Australian species ofVigna,CanavaliaandDesmodiummainly have tropical distributions and were considered poorly suited for semi-arid temperate cropping systems. Of the remaining generaGlycyrrhizaandCrotalariaspecies showed many suitable traits, including an erect growth habit, a low propensity to shatter, flowers and fruits borne at the end of branches and moderate to large seeds (5 and 38 mg, respectively). The species for which sufficient information was available that were considered highest priority for further investigation wereGlycine canescens, Cullen tenax, Swainsona canescens, Swainsona colutoides, Trigonella suavissima, Kennedia prorepens, Glycyrrhiza acanthocarpa, Crotalaria cunninghamiiandRhynchosia minima.
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Doole, Graeme J., Andrew D. Bathgate, and Michael J. Robertson. "Economic value of grazing vegetative wheat (Triticum aestivum L.) crops in mixed-farming systems of Western Australia." Animal Production Science 49, no. 10 (2009): 807. http://dx.doi.org/10.1071/ea08286.
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Livestock production in Western Australian mixed-farming systems has traditionally been constrained by a profound scarcity of feed in autumn–early winter when crop stubbles and pasture residues from the previous growing season have been exhausted. This study investigates the profitability of partially filling this ‘feed gap’ through the grazing of vegetative wheat crops. Whole-farm bioeconomic modelling is used to provide insight into the relative value of grazing and grain production in both low- and high-rainfall areas of Western Australia. Dual-purpose wheat crops are a valuable source of feed in high-rainfall areas as they provide an affordable alternative to expensive grain supplements for a short period in winter. This also allows annual pastures to establish more vigorously by reducing grazing pressure on young plants. Model output suggests farm profit can increase by over 10% with the grazing of vegetative wheat crops in high-rainfall regions; however, these results are logically shown to be strongly related to the assumed rate of yield loss. In contrast, at the parameter values used in this study, grazing wheats are unlikely to be profitable in low-rainfall environments due to depressed crop production and the extended feed gap experienced in these areas. Higher grain prices unequivocally lower the relative advantage of grazing activity since this elevates the cost of foregone grain yield.
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Ullah, Najeeb, Behnam Ababaei, and Karine Chenu. "Increasing Heat Tolerance in Wheat to Counteract Recent and Projected Increases in Heat Stress." Proceedings 36, no. 1 (March 28, 2020): 132. http://dx.doi.org/10.3390/proceedings2019036132.
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The frequency of heat shocks during grain filling of wheat crops across the Australian wheatbelt has significantly increased over the last 30 years. These post-flowering heat events significantly reduce wheat yields with a relatively greater impact on grain size than grain number. A controlled environment study was conducted to assess the impact of post-flowering heat shocks on wheat recombinant inbred lines SB062 and SB003. Plants were submitted to 7-day heat shocks (33/21 °C day/night temperature) at different periods during grain filling. Heat shocks significantly accelerated leaf senescence, with a greater impact on older leaves and for mid post-flowering stresses. Overall, the tolerant line (SB062) could maintain leaf greenness longer than the sensitive line (SB003), especially when submitted to heat stress. Further, heat shocks during early-to-mid grain filling reduced the grain size and weight. While the impact on developing grains was significant in SB003, no significant effect of post-flowering heat was observed on leaf senescence nor on grain size in the tolerant line SB062. Delayed leaf senescence appeared to play a role in maintaining grain size under heat stress. The research findings will assist improving crop models for post-flowering heat effects and developing techniques for screening heat tolerant wheat lines. Increased post-flowering assimilate production through sustained leaf greenness could improve the performance of wheat crops in increasingly warmer environments.
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Borger, Catherine P. D., Abul Hashem, and Shahab Pathan. "Manipulating Crop Row Orientation to Suppress Weeds and Increase Crop Yield." Weed Science 58, no. 2 (June 2010): 174–78. http://dx.doi.org/10.1614/ws-09-094.1.
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Crop rows oriented at a right angle to sunlight direction (i.e., east–west within the winter cropping system in Western Australia) may suppress weed growth through greater shading of weeds in the interrow spaces. This was investigated in the districts of Merredin and Beverley, Western Australian (latitudes of 31° and 32°S) from 2002 to 2005 (four trials). Winter grain crops (wheat, barley, canola, lupines, and field peas) were sown in an east–west or north–south orientation. Within wheat and barley crops oriented east–west, weed biomass (averaged throughout all trials) was reduced by 51 and 37%, and grain yield increased by 24 and 26% (compared with crops oriented north–south). This reduction in weed biomass and increase in crop yield likely resulted from the increased light (photosynthetically active radiation) interception by crops oriented east–west (i.e., light interception by the crop canopy as opposed to the weed canopy was 28 and 18% greater in wheat and barley crops oriented east–west, compared with north–south crops). There was no consistent effect of crop row orientation in the canola, field pea, and lupine crops. It appears that manipulation of crop row orientation in wheat and barley is a useful weed-control technique that has few negative effects on the farming system (i.e., does not cost anything to implement and is more environmentally friendly than chemical weed control).
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Blaney, BJ, and KC Williams. "Effective use in livestock feeds of mouldy and weather-damaged grain containing mycotoxins—case histories and economic assessments pertaining to pig and poultry industries of Queensland." Australian Journal of Agricultural Research 42, no. 6 (1991): 993. http://dx.doi.org/10.1071/ar9910993.
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Mould growth in field crops or stored grain reduces starch and lipid content, with consequent increases in fibre, and an overall reduction in digestible energy; palatability is often adversely affected. If these factors are allowed for, and mycotoxin concentrations are low, there are sound economic reasons for using this cheaper grain. Mycotoxins are common in stock feed but their effects on animal productivity are usually slight because either the concentration is too low or the animal is tolerant to the toxin. In Australia, aflatoxins occur in peanut by-products and in maize and sorghum if the grain is moist when stored. Zearalenone is found in maize and in sorghum and wheat in wetter regions. Nivalenol and deoxynivalenol are found in maize and wheat but at concentrations that rarely affect pigs, with chickens and cattle being even more tolerant. Other mycotoxins including cyclopiazonic acid, T-2 toxin, cytochalasins and tenuazonic acid are produced by Australian fungi in culture but are not found to be significant grain contaminants. Extremely mouldy sorghum containing Alternaria and Fusarium mycotoxins decreased feed conversion in pigs and chickens by up to 14%. However, E moniliforme- and Diplodia maydis-infected maize produced only slight reductions in feed intake by pigs and Ustilago-infected barley produced no ill effects. Use of these grains would substantially increase profits if the grain can be purchased cheaply.
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Pritchard, D. L., N. Penney, M. J. McLaughlin, H. Rigby, and K. Schwarz. "Land application of sewage sludge (biosolids) in Australia: risks to the environment and food crops." Water Science and Technology 62, no. 1 (July 1, 2010): 48–57. http://dx.doi.org/10.2166/wst.2010.274.
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Australia is a large exporter of agricultural products, with producers responsible for a range of quality assurance programs to ensure that food crops are free from various contaminants of detriment to human health. Large volumes of treated sewage sludge (biosolids), although low by world standards, are increasingly being recycled to land, primarily to replace plant nutrients and to improve soil properties; they are used in agriculture, forestry, and composted. The Australian National Biosolids Research Program (NBRP) has linked researchers to a collective goal to investigate nutrients and benchmark safe concentrations of metals nationally using a common methodology, with various other research programs conducted in a number of states specific to regional problems and priorities. The use of biosolids in Australia is strictly regulated by state guidelines, some of which are under review following recent research outcomes. Communication and research between the water industry, regulators and researchers specific to the regulation of biosolids is further enhanced by the Australian and New Zealand Biosolids Partnership (ANZBP). This paper summarises the major issues and constraints related to biosolids use in Australia using specific case examples from Western Australia, a member of the Australian NBRP, and highlights several research projects conducted over the last decade to ensure that biosolids are used beneficially and safely in the environment. Attention is given to research relating to plant nutrient uptake, particularly nitrogen and phosphorus (including that of reduced phosphorus uptake in alum sludge-amended soil); the risk of heavy metal uptake by plants, specifically cadmium, copper and zinc; the risk of pathogen contamination in soil and grain products; change to soil pH (particularly following lime-amended biosolids); and the monitoring of faecal contamination by biosolids in waterbodies using DNA techniques. Examples of products that are currently produced in Western Australia from sewage sludge include mesophilic anaerobically digested and dewatered biosolids cake, lime-amended biosolids, alum sludge and compost.
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Mutze, G. J. "The 1993 strychnine baiting program for mouse control in South Australian grain crops. I. Efficacy." Wildlife Research 25, no. 5 (1998): 533. http://dx.doi.org/10.1071/wr96009.
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The grain-growing areas of South Australia were affected by a severe mouse plague during the winter and spring of 1993. Damage to recently sown and maturing crops was minimised by broadcasting 0.3% strychnine-treated wheat across affected crops, at a rate of 1 kg ha-1. Three indices were used to measure relative mouse abundance before and after treatment: counts of active mouse holes, bait card consumption, and live-trapping. Hole counts and live-trapping both underestimated treatment effects. Bait card consumption provided the most accurate indication of treatment effects. In crops treated across their entire area, treatment reduced bait card consumption by 87%, with 95% reduction in 18 of 28 crops monitored. In most cases, baiting stopped damage by mice and allowed farmers to establish healthy crops where previously mice had removed all the seed sown, and resown, prior to treatment. Perimeter baiting was less successful owing to rapid reinvasion of treated areas, and reduced average bait card consumption by only 16%. Strychnine baiting in crop stubbles was ineffective where weed seeds were abundant.
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Gu, H., O. R. Edwards, A. T. Hardy, and G. P. Fitt. "Host plant resistance in grain crops and prospects for invertebrate pest management in Australia: an overview." Australian Journal of Experimental Agriculture 48, no. 12 (2008): 1543. http://dx.doi.org/10.1071/ea08027.
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An integrated pest management (IPM) approach that relies on an array of tactics is adopted commonly in response to problems with pesticide-based production in many agricultural systems. Host plant resistance is often used as a fundamental component of an IPM system because of the generally compatible, complementary role that pest-resistant crops play with other tactics. Recent research and development in the resistance of legumes and cereals to aphids, sorghum midge resistance, and the resistance of canola varieties to mite and insect pests have shown the prospects of host plant resistance for developing IPM strategies against invertebrate pests in Australian grain crops. Furthermore, continuing advances in biotechnology provide the opportunity of using transgenic plants to enhance host plant resistance in grains.
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Robertson, M. J., R. A. Lawes, A. Bathgate, F. Byrne, P. White, and R. Sands. "Determinants of the proportion of break crops on Western Australian broadacre farms." Crop and Pasture Science 61, no. 3 (2010): 203. http://dx.doi.org/10.1071/cp09207.
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Break crops (e.g. pulses, lupins, canola, oats) underpin the continued profitability of cereal (wheat or barley) based cropping sequences. The area sown on farms to break crops varies widely across geographical regions according to climate, soil type mix, enterprise mix (crop v. livestock), and other constraints such as the prevalence of soil-borne disease. Given recent fluctuations in the area of established break crops in Western Australia, there are concerns about their long-term prospects in the farming system. A survey of the area and grain yield of break crops on-farm was combined with whole-farm bio-economic modelling to determine the upper limit to the area of break crops on representative farms in 4 agro-climatic regions. Sensitivity analysis was conducted to ascertain the potential effects of varying commodity prices (sheep and grain), costs of production, and assumptions on the yield of break crops and the boost to the yield of following cereals. The survey revealed that the two dominant break crops, lupins and canola, occupied 8–12% and 8–9%, respectively, of farm area on those farms that grew them in the medium-rainfall zone and this declined to 6–8% and 7–10% in the drier region. Nevertheless, the modelling results show that break crops are an important component of the farming system, even where the area is small, and the response of whole-farm profit to percent of the farm allocated to break crops is relatively flat near the optimum of 23–38%. The modelled area of break crops at maximum profit is higher than that found in farm surveys. The discrepancy could possibly be explained by the lower break crop yields realised by farmers and a reduced boost to cereal yields following break crops than assumed in models. Also, deterministic models do not account for risk, which is an important consideration in the decision to grow break crops. However, the yield difference does not explain the discrepancy entirely and raises questions about farmer motivations for adoption of break crops. The scope for increased area of break crops beyond 23–38% of the farm is limited, even with increases in the yield enhancements in subsequent cereal crops, higher break crop prices, and higher fertiliser costs. Further research is required to better quantify costs and benefits of break crops in Western Australian farming systems.
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Peoples, Mark B., Antony D. Swan, Laura Goward, John A. Kirkegaard, James R. Hunt, Guangdi D. Li, Graeme D. Schwenke, et al. "Soil mineral nitrogen benefits derived from legumes and comparisons of the apparent recovery of legume or fertiliser nitrogen by wheat." Soil Research 55, no. 6 (2017): 600. http://dx.doi.org/10.1071/sr16330.
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Nitrogen (N) contributed by legumes is an important component of N supply to subsequent cereal crops, yet few Australian grain-growers routinely monitor soil mineral N before applying N fertiliser. Soil and crop N data from 16 dryland experiments conducted in eastern Australia from 1989–2016 were examined to explore the possibility of developing simple predictive relationships to assist farmer decision-making. In each experiment, legume crops were harvested for grain or brown-manured (BM, terminated before maturity with herbicide), and wheat, barley or canola were grown. Soil mineral N measured immediately before sowing wheat in the following year was significantly higher (P < 0.05) after 31 of the 33 legume pre-cropping treatments than adjacent non-legume controls. The average improvements in soil mineral N were greater for legume BM (60 ± 16 kg N/ha; n = 5) than grain crops (35 ± 20 kg N/ha; n = 26), but soil N benefits were similar when expressed on the basis of summer fallow rainfall (0.15 ± 0.09 kg N/ha per mm), residual legume shoot dry matter (9 ± 5 kg N/ha per t/ha), or total legume residue N (28 ± 11%). Legume grain crops increased soil mineral N by 18 ± 9 kg N/ha per t/ha grain harvested. Apparent recovery of legume residue N by wheat averaged 30 ± 10% for 20 legume treatments in a subset of eight experiments. Apparent recovery of fertiliser N in the absence of legumes in two of these experiments was 64 ± 16% of the 51–75 kg fertiliser-N/ha supplied. The 25 year dataset provided new insights into the expected availability of soil mineral N after legumes and the relative value of legume N to a following wheat crop, which can guide farmer decisions regarding N fertiliser use.
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Evans, J., A. M. McNeill, M. J. Unkovich, N. A. Fettell, and D. P. Heenan. "Net nitrogen balances for cool-season grain legume crops and contributions to wheat nitrogen uptake: a review." Australian Journal of Experimental Agriculture 41, no. 3 (2001): 347. http://dx.doi.org/10.1071/ea00036.
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The removal of nitrogen (N) in grain cereal and canola crops in Australia exceeds 0.3 million t N/year and is increasing with improvements in average crop yields. Although N fertiliser applications to cereals are also rising, N2-fixing legumes still play a pivotal role through inputs of biologically fixed N in crop and pasture systems. This review collates Australian data on the effects of grain legume N2 fixation, the net N balance of legume cropping, summarises trends in the soil N balance in grain legume–cereal rotations, and evaluates the direct contribution of grain legume stubble and root N to wheat production in southern Australia. The net effect of grain legume N2 fixation on the soil N balance, i.e. the difference between fixed N and N harvested in legume grain (Nadd) ranges widely, viz. lupin –29–247 kg N/ha (mean 80), pea –46–181 kg N/ha (mean 40), chickpea –67–102 kg N/ha (mean 6), and faba bean 8–271 kg N/ha (mean 113). Nadd is found to be related to the amount (Nfix) and proportion (Pfix) of crop N derived from N2 fixation, but not to legume grain yield (GY). When Nfix exceeded 30 (lupin), 39 (pea) and 49 (chickpea) kg N/ha the N balance was frequently positive, averaging 0.60 kg N/kg of N fixed. Since Nfix increased with shoot dry matter (SDM) (21 kg N fixed/t SDM; pea and lupin) and Pfix (pea, lupin and chickpea), increases in SDM and Pfix usually increased the legume’s effect on soil N balance. Additive effects of SDM, Pfix and GY explained most (R2 = 0.87) of the variation in Nadd. Using crop-specific models based on these parameters the average effects of grain legumes on soil N balance across Australia were estimated to be 88 (lupin), 44 (pea) and 18 (chickpea) kg N/ha. Values of Nadd for the combined legumes were 47 kg N/ha in south-eastern Australia and 90 kg N/ha in south-western Australia. The average net N input from lupin crops was estimated to increase from 61 to 79 kg N/ha as annual rainfall rose from 445 to 627 mm across 3 shires in the south-east. The comparative average input from pea was 37 to 47 kg N/ha with least input in the higher rainfall shires. When the effects of legumes on soil N balance in south-eastern Australia were compared with average amounts of N removed in wheat grain, pea–wheat (1:1) sequences were considered less sustainable for N than lupin–wheat (1:1) sequences, while in south-western Australia the latter were considered sustainable. Nitrogen mineralised from lupin residues was estimated to contribute 40% of the N in the average grain yield of a following wheat crop, and that from pea residues, 15–30%; respectively, about 25 and 15 kg N/ha. Therefore, it was concluded that the majority of wheat N must be obtained from pre-existing soil sources. As the amounts above represented only 25–35% of the total N added to soil by grain legumes, the residual amount of N in legume residues is likely to be important in sustaining those pre-existing soil sources of N.
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Blaney, Barry J., John B. Molloy, and Ian J. Brock. "Alkaloids in Australian rye ergot (Claviceps purpurea) sclerotia: implications for food and stockfeed regulations." Animal Production Science 49, no. 11 (2009): 975. http://dx.doi.org/10.1071/an09030.
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Rye ergot (Claviceps purpurea) occasionally causes toxicity (chiefly expressed as hyperthermia) in Australian livestock, either as a result of grazing infected annual (Lolium rigidum) and perennial (L. perenne) rye grasses, or if the ergot sclerotia produced in rye grasses contaminate grain crops used as stockfood. Alkaloids in 30 samples of Australian rye ergot sclerotia taken from rye grasses and grain screenings, and some feed samples contaminated with rye grass ergot sclerotia, were assayed by high performance liquid chromatography. Samples originated from across southern Australia. Ergotamine was the dominant alkaloid in all samples, followed by α-ergocryptine, ergocornine, ergosine and their respective -imine epimers. Ergotamine concentrations in sclerotia ranged up to 2257 mg/kg (as received basis). Ergocristine was a very minor component (<50 mg/kg) in all samples. Total alkaloids in freshly collected sclerotia ranged from 1003 to 3321 mg/kg (0.10 to 0.33%), and up to 3766 mg/kg with epimers included, although lower concentrations were found in samples stored for some time. Alkaloid profiles in sclerotia were all very similar, and concentrations did not appear to be related to size of sclerotia, source region, nor to the rye grass or grain from which they were taken. Previous cases of toxicity in livestock are reviewed and several new cases are reported. The implications of variable alkaloid contents of rye ergot sclerotia are discussed in terms of Australian food and stockfeed regulations.
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Wright, Dominie, Bill MacLeod, Nichole Hammond, and Nancy Longnecker. "Can grain growers and agronomists identify common leaf diseases and biosecurity threats in grain crops? An Australian example." Crop Protection 89 (November 2016): 78–88. http://dx.doi.org/10.1016/j.cropro.2016.07.005.
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Shabbir, Asad, Bhagirath S. Chauhan, and Michael J. Walsh. "Biology and management of Echinochloa colona and E. crus-galli in the northern grain regions of Australia." Crop and Pasture Science 70, no. 11 (2019): 917. http://dx.doi.org/10.1071/cp19261.
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Echinochloa colona and E. crus-galli are two important annual grass weeds distributed throughout the summer cropping regions of Australia. Both species are highly problematic weeds, responsible for yield losses of up to 50% in summer grain crops. The success of Echinochloa species as weeds is attributed to their rapid growth, prolific seed production, seed dormancy and adaptability to a wide range of environments. Importantly, E. colona has evolved resistance to glyphosate in Australia, with resistant populations now widespread across the summer cropping regions. Fallow management of E. colona with glyphosate alone is risky in terms of increasing the chance of resistance and highly unsustainable; other control strategies (residual herbicides, strategic tillage, etc.) should be considered to complement herbicides. This review provides a summary of current information on the biology, ecology and management of Echinochloa species. The knowledge gaps and research opportunities identified will have pragmatic implications for the management of these species in Australian grain cropping systems.
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Turner, NC. "Crop production on duplex soils: an introduction." Australian Journal of Experimental Agriculture 32, no. 7 (1992): 797. http://dx.doi.org/10.1071/ea9920797.
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Duplex or texture-contrast soils occur over about 60% of the agricultural areas of south-west Western Australia. Annual crops of wheat, barley, oats, and lupins predominate on these soils, grown in rotation with annual pastures. The climate is characterised by cool, wet winters and hot, dry summers. Crop production is restricted to the winter and spring and is limited by waterlogging in the wet winter months and by water shortage during grain filling in spring. Research on crop production on duplex soils has been undertaken for the past 8 years by a collaborative team from the CSIRO Dryland Crops andyoils Program and the Western Australian Department of Agriculture. This research has been focussed on 3 sites at which processes limiting crop production on duplex soils have been highlighted. This special issue was initiated to summarise that research and to put it in its regional and national perspective. Additionally, opportunity was taken to compare and contrast experiences both within Western Australia and throughout Australia, and to draw out management options for crop production on duplex soils.
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Fillery, IR, and KJ McInnes. "Components of the fertiliser nitrogen balance for wheat production on duplex soils." Australian Journal of Experimental Agriculture 32, no. 7 (1992): 887. http://dx.doi.org/10.1071/ea9920887.
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In this paper, we review literature on the fate of fertiliser nitrogen (N) applied to duplex soils in wheat-growing regions of southern Australia, and discuss the contribution of specific N transformations to N loss. Duplex soils are characterised by the presence of soil material, within the rooting depth of crops, that possess hydraulic conductivities that are lower than those of overlying material. Denitrification and the transport of nitrate below rooting depth of crops are thought to be the chief causes of loss of fertiliser N and to contribute to poor grain yields. Ammonia volatilisation could contribute also to N loss. The fate of fertiliser N commonly applied to wheat in southern Australia has largely been evaluated using budgeting procedures using l5N, a stable isotope of N. Results from studies in south-eastem Australia, using red-brown earths, indicate that between 10 and 40% of applied 15N can be lost irrespective of time of application to wheat. Denitrification is believed to be the chief cause of loss of l5N. Similar studies on yellow duplex soils in Western Australia have shown fertiliser N loss to range from 70% to no loss of the l5N applied. The exact cause of N loss in Western Australian studies is unclear. There was circumstantial evidence for ammonia loss from surface-applied urea, and evidence of leaching of nitrates from this and other ammoniumbased fertilisers. The role of denitrification has not been clarified in Western Australian studies. In the majority of studies, recovery of 15N in aboveground biomass exceeded 40% of that applied. In addition, between 17 and 48% of applied 15N, of which 10-15% may be in root material, has been recovered in the soil organic matter pool. The predominance of the denitrification process in south-eastern Australian soils, and the inability to improve the efficiency of utilisation of 15N by delaying the time of application to wheat underscores the importance of controlling the nitrification process using inhibitors. Management options for Western Australian soils are less clear. Some agronomic experiments have demonstrated the advantage of delaying the application of fertiliser N to wheat to improve the efficiency of its utilisation. There is also evidence which suggests that N should be applied early in the growth cycle to promote tiller development and thereby increase the potential for grain yield.
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Michael, Pippa J., Mechelle J. Owen, and Stephen B. Powles. "Herbicide-Resistant Weed Seeds Contaminate Grain Sown in the Western Australian Grainbelt." Weed Science 58, no. 4 (December 2010): 466–72. http://dx.doi.org/10.1614/ws-d-09-00082.1.
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Preventing the introduction of weeds into the farming system through sowing of clean seeds is an essential component of weed management. The weed seed contamination of cleaned grain and herbicide resistance levels of the recovered weed seeds were examined in a study conducted across 74 farms in the Western Australian grainbelt. Most farmers grew and conserved their own crop seed. The majority of cleaned samples had some level of seed contamination from 11 foreign weed and volunteer crop species, with an average of 62 seeds 10 kg−1grain, substantially higher than the 28 seeds 10 kg−1grain expected by farmers. The most common weed contaminants across all samples were rigid ryegrass, wild radish, brome, and wild oat. When categorized by crop type, rigid ryegrass was the most frequent contaminant of cereal crops (barley and wheat), however wild radish was the most frequent contaminant of lupin crops. Uncleaned crop seed samples had almost 25 times more contamination than cleaned crop seed. Herbicide resistance was highly prevalent within rigid ryegrass populations recovered from cleaned grain except for glyphosate, which controlled all populations tested. Some resistance was also found in wild radish and wild oat populations; however, brome was susceptible to fluazifop. This study has shown that farmers are unknowingly introducing weed seeds into their farming systems during crop seeding, many of which have herbicide resistance.
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Hocking, P. J., and M. J. McLaughlin. "Genotypic variation in cadmium accumulation by seed of linseed, and comparison with seeds of some other crop species." Australian Journal of Agricultural Research 51, no. 4 (2000): 427. http://dx.doi.org/10.1071/ar99124.
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The accumulation of cadmium (Cd) in plants is a health issue because a range of grain and vegetable crops can accumulate levels of Cd that are in excess of limits set by the World Health Organization and individual countries. Many Australian agricultural soils used to produce confectionery linseed have a history of intensive use of Cd-contaminated phosphatic fertilisers and this, combined with soil properties such as high chloride salinity, can result in enhanced availability of Cd to crops. We investigated genotypic variation in Cd accumulation in seed of 17 linseed and Linola (termed linseed) lines from Australia and elsewhere in a glasshouse study using a soil from southern Australia that had a history of the application of Cd-contaminated phosphatic fertiliser. Canola, Indian mustard, lupins, and wheat were also included in the study for comparison. Under the experimental conditions, Cd concentrations in seed of all but one of the linseed lines exceeded the maximum permitted concentration (MPC) of 250 µg/kg for confectionery linseed traded on the international market. There was a 2.3-fold variation in seed Cd concentrations between all the linseed lines (range, 233–545 µg/kg). Linseed lines from Australia and overseas were equally capable of accumulating Cd in seed. Brown-seeded and golden-seeded lines accumulated similar concentrations of Cd. Canola, Indian mustard, lupins, and wheat accumulated about 10-fold lower concentrations of Cd in seed than linseed, and did not exceed Australian or other MPCs. There was little difference in Cd concentrations between the seed and de-seeded capsules of linseed, but a large difference in Cd concentration between the seed and de-seeded fruit parts of the other crops. The mean seed to de-seeded fruit part Cd concentration ratio for linseed was 0.87 : 1 compared with a ratio of 0.35 : 1 for the other crops, suggesting that linseed has comparatively ineffective barriers discriminating against the transport of Cd to seed. Analysis of seed lots of confectionery linseed sampled from a grain receival depot showed that seed lots from farms in Victoria (range 140–560 µg Cd/kg) had 5-fold greater Cd concentrations than those from farms in New South Wales (range 20–160 µg/kg). This is presumably due to a more intensive history of the application of Cd-contaminated phosphatic fertiliser to pastures and crops in Victoria, as well as differences in environmental and soil conditions.
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Bell, Lindsay W., Megan H. Ryan, Richard G. Bennett, Margaret T. Collins, and Heather J. Clarke. "Growth, yield and seed composition of native Australian legumes with potential as grain crops." Journal of the Science of Food and Agriculture 92, no. 7 (November 14, 2011): 1354–61. http://dx.doi.org/10.1002/jsfa.4706.
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Mutze, Greg, and Ron Sinclair. "Efficacy of zinc phosphide, strychnine and chlorpyrifos as rodenticides for the control of house mice in South Australian cereal crops." Wildlife Research 31, no. 3 (2004): 249. http://dx.doi.org/10.1071/wr02027.
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Replicated field trials were conducted to compare the efficacy of zinc phosphide, strychnine and chlorpyrifos for the control of house mice (Mus domesticus) infesting recently sown wheat crops in South Australia. Bait was prepared using whole-wheat grain or grain-based pellets and broadcast into the crops at 1 kg ha–1. Treatment with zinc phosphide reduced mouse numbers by 98%. Two treatments with strychnine baits, applied 11 days apart, also reduced mouse numbers by 98% with no evidence of bait aversion in mice that survived the initial treatment. On the basis of these and other published results, zinc phosphide is considered an effective alternative to strychnine for control of house mice in cereal crops. Chlorpyrifos baits reduced mouse numbers by less than 10%. The trial began too late in the growing season to prevent substantial mouse damage to seed grain and seedlings. The number of seedlings established at treatment time one month after sowing explained 84% of variation in crop yield. Mouse damage is estimated to have reduced yield by more than 0.5 t ha–1 or 15% of potential yield and cost the grower more than $30 000 in lost production from the 300-ha study area.
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Owen, K. J., T. G. Clewett, and J. P. Thompson. "Pre-cropping with canola decreased Pratylenchus thornei populations, arbuscular mycorrhizal fungi, and yield of wheat." Crop and Pasture Science 61, no. 5 (2010): 399. http://dx.doi.org/10.1071/cp09345.
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Root-lesion nematode (Pratylenchus thornei) significantly reduces wheat yields in the northern Australian grain region. Canola is thought to have a ‘biofumigation’ potential to control nematodes; therefore, a field experiment was designed to compare canola with other winter crops or clean-fallow for reducing P. thornei population densities and improving growth of P. thornei-intolerant wheat (cv. Batavia) in the following year. Immediately after harvest of the first-year crops, populations of P. thornei were lowest following various canola cultivars or clean-fallow (1957–5200 P. thornei/kg dry soil) and were highest following susceptible wheat cultivars (31 033–41 294/kg dry soil). Unexpectedly, at planting of the second-year wheat crop, nematode populations were at more uniform lower levels (<5000/kg dry soil), irrespective of the previous season’s treatment, and remained that way during the growing season, which was quite dry. Growth and grain yield of the second-year wheat crop were poorest on plots previously planted with canola or left fallow due to poor colonisation with arbuscular mycorrhizal (AM) fungi, with the exception of canola cv. Karoo, which had high AM fungal colonisation and low wheat yields. There were significant regressions between growth and yield parameters of the second-year wheat and levels of AMF following the pre-crop treatments. Thus, canola appears to be a good crop for reducing P. thornei populations, but AM fungal-dependence of subsequent crops should be considered, particularly in the northern Australian grain region.
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Angus, J. F. "Nitrogen supply and demand in Australian agriculture." Australian Journal of Experimental Agriculture 41, no. 3 (2001): 277. http://dx.doi.org/10.1071/ea00141.
Full textAbstract:
The supply of and demand for nitrogen by whole industries and individual crops is discussed in relation to changes in farming systems, particularly the relative importance of fertiliser and biologically fixed nitrogen. The use of fertiliser nitrogen (N) in Australia has grown at an annual rate of 14% since the early 1990s, after growing at half that rate since the 1950s. The accelerated growth occurred during a period when world demand has been almost constant. Most of the additional demand has been for the dryland cereal and canola industries of southern Australia, where crops previously obtained almost all their N from mineralisation of soil organic matter and the residues of legume pastures. The most likely reasons for the belated increase in use of fertiliser N in Australia are to replace the supply from pasture residues as the area of pasture decreased and to satisfy the increased demand of cereals following break crops and of the break crops themselves, particularly canola. For a dryland cereal, there is a problem of matching soil N supply with an unpredictable N demand. For winter cereals in Australia, crop N demand is poorly synchronised with soil N supply. The time of greatest demand is normally during the stem-elongation phase when the crop is growing fastest. For crops targeted for high-protein grain, there is an even greater demand around the flowering phase. The peak N demand for well-managed crops growing with no water limitations exceeds the capacity of the soil to supply N from mineralisation at the time, so additional N is required to meet the shortfall, either from fertiliser or mineral N retained in the soil from earlier mineralisation. Predicting the optimum supply of fertiliser N at sowing is difficult in cases where N demand is influenced by variable rainfall. Topdressing and banding fertiliser offer prospects for more closely matching N supply and demand for dryland crops. The future role of legumes in supplying residual N is discussed in relation to the trend towards continuous cropping.
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Forrester, Neil W., Matthew Cahill, Lisa J. Bird, and Jacquelyn K. Layland. "Section 1. The Australian insecticide resistance management strategy." Bulletin of entomological research supplement series 1 (September 1993): 1–4. http://dx.doi.org/10.1017/s1367426900000072.
Full textAbstract:
SummaryIn response to field pyrethroid failures against Helicoverpa armigera (Hübner) in early 1983, an insecticide resistance management (IRM) strategy was introduced for insect control in summer crops in eastern Australia. The aims of this strategy were to contain the pyrethroid resistance problem, to prevent re-selection of historical endosulfan resistance (both curative IRM) and to avoid any future problems with organophosphate/carbamate resistance (preventative IRM). An alternation strategy was adopted which was based on the rotation of unrelated chemical groups on a per generation basis, along with a strong recommendation for the use of ovicidal mixtures. These chemical countermeasures were then integrated with other non-chemical control methods (biological and cultural) into a workable integrated pest management programme. The restrictions were applied to all Helicoverpa armigera susceptible crops (including cereals, oilseeds, grain legumes, tomatoes, tobacco and cotton) and even to other co-incident pest species. From its inception, compliance with the voluntary strategy has been exceptional.
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Wood, Jennifer A., and J. Fiona Scott. "Economic impacts of chickpea grain classification: how ‘seed quality is Queen’ must be considered alongside ‘yield is King’ to provide a princely income for farmers." Crop and Pasture Science 72, no. 2 (2021): 136. http://dx.doi.org/10.1071/cp20282.
Full textAbstract:
Chickpeas (Cicer arietinum L.) are a high value crop for farmers, but price penalties will be imposed or grain rejected whenever the standards are not met by growers whose crops suffer grain defects in a particular season. Australian chickpeas are renowned for their high quality and are generally in high demand globally because of good farming practice and strict grain quality standards. However, small quantities of defective seed in grain loads can reduce the price paid to individual farmers, with significant financial impacts. Information is scarce on the types of defects causing price penalties and there is no information on the magnitude of those penalties. An online farmer survey was conducted to capture information on the types of grain defects, price penalties imposed and load rejections with respect to the delivery of their 2017 chickpea crop. Here we show that the cost to individual chickpea farmers affected by price penalties or load rejections ranged from AU$743 to $1293750. Furthermore, the total cost of seed defects was calculated to be $154.2 million in that season, equating to a revenue loss of 23.7% of gross value of production in Australia. Chickpea seed defects also contributed to additional costs including seed cleaning, further transport costs and harvest delays, with subsequent risk of yield losses and further quality defects. Too often, crop yields are the focus while seed quality is overlooked as an essential driver of farmer profitability. We demonstrate how important seed quality is to farmer profitability; if ‘yield is King’ then seed quality is certainly Queen. We suggest that farmers prioritise harvest of their chickpea crops ahead of harvest of cereal crops to minimise the risk of chickpea seed defects and seed loss, and to maximise profits from this higher value crop. Additional surveys over several seasons are warranted to refine information on the types of seed defects occurring in chickpea and their financial impacts on farmers, and they could be expanded to other crops and countries. We suggest that misclassification of seed defects needs further exploration, as does research into minimising the major causes of seed defects. Improvements to grain classification systems globally should be sought to provide better support for farmer profitability so that they can continue to feed the world.
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Silsbury, JH. "Nodulation and nitrogen fixation (acetylene reduction) of four cultivars of chickpea." Australian Journal of Experimental Agriculture 29, no. 5 (1989): 663. http://dx.doi.org/10.1071/ea9890663.
Full textAbstract:
The capacities of 4 Australian cultivars of chickpea to nodulate, grow and to fix N2 after inoculation with commercial peat inoculant (Group N, strain CC1192) were examined up to flowering in 2 experiments. One was a field experiment and the other a glasshouse pot experiment involving application of mineral (NO-3) N. Nodule activity was estimated by acetylene reduction assay (AR). The study was conducted in response to recent reports and field observations of apparently poor fixation by chickpea crops in South Australia and of poor cereal yield following a chickpea crop. The cultivars Dooen, Tyson, Opal and Amethyst all nodulated successfully with the inoculant and fixed N2 actively over the vegetative period, although plants were slow to nodulate under warm conditions. A sharp decline in nodule activity was not observed at flowering but observations were not continued into the grain-filling period. A nutrient solution 2.5 mmol/L for NO-3 (compared with no NOT) applied 14 days after sowing, delayed nodulation, had no effect on total nodule number 50 days after sowing but markedly reduced nodule activity of all cultivars. Cultivars showed only small differences in nodule number and in nodule activity; but all showed a strong, positive, growth response to NO-3 and accumulated more N when NO-3 was applied than when only N2 was fixed. It was concluded that all 4 cultivars were adequately nodulated by strain CC1192, which led to active N2 fixation during the vegetative period. Poor apparent fixation by chickpea crops in the field may be due to decline in nodule activity during grain filling and mobilisation of plant N to the grain, or to the use of soil mineral N rather than fixed N2. If chickpea is to gain a useful place in cereal-grain legume rotations in southern Australia, grain yield needs to be increased, dependence on soil N reduced and nodule activity prolonged into the grain filling period. These objectives may be achievable in part through the identification and eventual use of an inoculant other than CC1192.
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Moore, Andrew D. "Opportunities and trade-offs in dual-purpose cereals across the southern Australian mixed-farming zone: a modelling study." Animal Production Science 49, no. 10 (2009): 759. http://dx.doi.org/10.1071/an09006.
Full textAbstract:
Dual-purpose cereals are employed in the high-rainfall zone of southern Australia to provide additional winter forage. Recently there has been interest in applying this technology in the drier environments of South and Western Australia. It would therefore be useful to gain an understanding of the trade-offs and risks associated with grazing wheat crops in different locations. In this study the APSIM (Agricultural Production Systems Simulator) crop and soil simulation models were linked to the GRAZPLAN pasture and livestock models and used to examine the benefits and costs of grazing cereal crops at 21 locations spanning seven of the regions participating in the Grain & Graze research, development and extension program. A self-contained part of a mixed farm (an annual pasture–wheat rotation plus permanent pastures) supporting a breeding ewe enterprise was simulated. At each location the consequences were examined of: (i) replacing a spring wheat cultivar with a dual-purpose cultivar (cv. Wedgetail or Tennant) in 1 year of the rotation; and (ii) either grazing that crop in winter, or leaving it ungrazed. The frequency of early sowing opportunities enabling the use of a dual-purpose cultivar was high. When left ungrazed the dual-purpose cultivars yielded less grain on average (by 0.1–0.9 t/ha) than spring cultivars in Western Australia and the Eyre Peninsula but more (by 0.25–0.8 t/ha) in south-eastern Australia. Stocking rate and hence animal production per ha could be increased proportionately more when a dual-purpose cultivar was used for grazing; because of the adjustments to stocking rates, grazing of the wheat had little effect on lamb sale weights. Across locations, the relative reduction in wheat yield caused by grazing the wheats was proportional to the grazing pressure upon them. Any economic advantage of moving to a dual-purpose system is likely to arise mainly from the benefit to livestock production in Western Australia, but primarily from grain production in south-eastern Australia (including the Mallee region). Between years, the relationship between increased livestock production and decreased grain yield from grazing crops shifts widely; it may therefore be possible to identify flexible grazing rules that optimise this trade-off.
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Siddique, K. H. M., and J. Sykes. "Pulse production in Australia past, present and future." Australian Journal of Experimental Agriculture 37, no. 1 (1997): 103. http://dx.doi.org/10.1071/ea96068.
Full textAbstract:
Summary. Several cool- and warm-season pulse crops (grain legumes) are grown in rotation with cereals and pasture forming sustainable farming systems in Australia. Australian pulse production has increased rapidly over the past 25 years to about 2 x 106 t/year, mainly because of the increase in the area and yield of lupin production for stockfeed purposes. Pulses currently comprise only 10% of the cropping areas of Australia and this could be expanded to 16% as there are large areas of soil types suitable for a range of pulse crops and new better-adapted pulse varieties are becoming available. Cool-season pulses will continue to dominate pulse production in Australia and the majority of the expansion will probably come from chickpea and faba bean industries. There appears to be no major constraint to pulse production in Australia that cannot be addressed by breeders, agronomists and farmers. Of the current major pulse crops, field pea faces the most number of difficulties, in particular the lack of disease management options. A recent strategic plan of the Australian pulse industry predicts the production of 4 x 106 t/year by 2005 but this will largely depend upon export demand and pulse prices. It is predicted that the growth in pulse production will come from increased productivity in the existing areas, from 1.0 to 1.4 t/ha, through improvements in crop management and the development of superior varieties. The area of pulse production will also expand by an additional 1.2 x 106 ha probably yielding 1.0 t/ha. If trends in grazing stock prices continue, the increased area under pulse production will mostly come at the expense of those areas under unimproved pasture and continuous cereal cropping.
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Bell, Michael J., Wayne Strong, Denis Elliott, and Charlie Walker. "Soil nitrogen—crop response calibration relationships and criteria for winter cereal crops grown in Australia." Crop and Pasture Science 64, no. 5 (2013): 442. http://dx.doi.org/10.1071/cp12431.
Full textAbstract:
More than 1200 wheat and 120 barley experiments conducted in Australia to examine yield responses to applied nitrogen (N) fertiliser are contained in a national database of field crops nutrient research (BFDC National Database). The yield responses are accompanied by various pre-plant soil test data to quantify plant-available N and other indicators of soil fertility status or mineralisable N. A web application (BFDC Interrogator), developed to access the database, enables construction of calibrations between relative crop yield ((Y0/Ymax) × 100) and N soil test value. In this paper we report the critical soil test values for 90% RY (CV90) and the associated critical ranges (CR90, defined as the 70% confidence interval around that CV90) derived from analysis of various subsets of these winter cereal experiments. Experimental programs were conducted throughout Australia’s main grain-production regions in different eras, starting from the 1960s in Queensland through to Victoria during 2000s. Improved management practices adopted during the period were reflected in increasing potential yields with research era, increasing from an average Ymax of 2.2 t/ha in Queensland in the 1960s and 1970s, to 3.4 t/ha in South Australia (SA) in the 1980s, to 4.3 t/ha in New South Wales (NSW) in the 1990s, and 4.2 t/ha in Victoria in the 2000s. Various sampling depths (0.1–1.2 m) and methods of quantifying available N (nitrate-N or mineral-N) from pre-planting soil samples were used and provided useful guides to the need for supplementary N. The most regionally consistent relationships were established using nitrate-N (kg/ha) in the top 0.6 m of the soil profile, with regional and seasonal variation in CV90 largely accounted for through impacts on experimental Ymax. The CV90 for nitrate-N within the top 0.6 m of the soil profile for wheat crops increased from 36 to 110 kg nitrate-N/ha as Ymax increased over the range 1 to >5 t/ha. Apparent variation in CV90 with seasonal moisture availability was entirely consistent with impacts on experimental Ymax. Further analyses of wheat trials with available grain protein (~45% of all experiments) established that grain yield and not grain N content was the major driver of crop N demand and CV90. Subsets of data explored the impact of crop management practices such as crop rotation or fallow length on both pre-planting profile mineral-N and CV90. Analyses showed that while management practices influenced profile mineral-N at planting and the likelihood and size of yield response to applied N fertiliser, they had no significant impact on CV90. A level of risk is involved with the use of pre-plant testing to determine the need for supplementary N application in all Australian dryland systems. In southern and western regions, where crop performance is based almost entirely on in-crop rainfall, this risk is offset by the management opportunity to split N applications during crop growth in response to changing crop yield potential. In northern cropping systems, where stored soil moisture at sowing is indicative of minimum yield potential, erratic winter rainfall increases uncertainty about actual yield potential as well as reducing the opportunity for effective in-season applications.
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Owen, Mechelle J., and Stephen B. Powles. "Lessons learnt: crop-seed cleaning reduces weed-seed contamination in Western Australian grain samples." Crop and Pasture Science 71, no. 7 (2020): 660. http://dx.doi.org/10.1071/cp20093.
Full textAbstract:
Weeds are a major contributing factor to crop yield loss. Weed control is regularly practiced during the growing season, with many growers making a conscious effort to minimise weed-seed return to the soil seedbank during the cropping program. However, growers may be unintentionally introducing weed seeds through sowing of contaminated crop seed. Using samples of crop seed obtained from 29 growers across two Western Australian grain-growing regions, 81 samples were hand-cleaned to determine weed-seed contamination levels. Of those samples, 41% were weed-free, and in the remaining 59%, the main contaminant was Lolium rigidum (annual ryegrass), occurring in 49% of contaminated samples. Crop type and cleaning method had significant effects on the level of weed-seed contamination, with barley having higher levels of contamination than other crops, and professional contractors providing lower contamination than other methods of cleaning. However, any seed-cleaning method provided significantly cleaner grain samples than no seed cleaning. This study established that crop-seed contamination was evident on Western Australian farms and that growers may be unintentionally sowing weed seeds with their crops. Seed cleaning combined with judicious paddock selection and weed-seed removal during the growing season can lead to weed-free crop seed.