Perennial legumes in the Dorycnium genus may have potential as forage plants that could reduce the seasonality of feed production and improve the sustainability of agricultural systems. However, Dorycnium species are not currently used commercially and little is known about their agronomic characteristics. This review covers the current knowledge on Dorycnium distribution, taxonomy and the agronomic performance of Dorycnium hirsutum, Dorycnium rectum and Dorycnium pentaphyllum, including adaptation, establishment, biomass production, water use, grazing management and nitrogen fixation, along with considerations for animal production. Dorycnium originate from temperate Europe and the Mediterranean basin and may be suitable for other regions with similar climatic conditions. Little data exist on the climatic and edaphic conditions to which Dorycnium species are best adapted. Current evidence suggests that D. hirsutum is widely adapted and might be suitable as a forage plant for acid soils in drier and frost-prone agricultural regions. D. hirsutum also persists well in low rainfall environments (down to 300 mm mean annual rainfall), can produce up to 21 t dry matter(DM)/ha in its first 3 years and, by utilising extra water compared with annual pastures, can reduce water leakage below the root zone, thereby slowing development of dryland salinity. The use of D. rectum would be limited to high rainfall or water-accumulating sites. D. pentaphyllum is a diverse species, yet available material appears to be less productive but has better forage quality than D. hirsutum. Currently, establishment reliability and/or forage digestibility are major limitations of the tested Dorycnium species that restrict their potential role and challenge the feasibility of their future use. Breeding may overcome or minimise these limitations and improved agronomic management might also enhance their usefulness. However, current collected genetic resources of Dorycnium are very limited and targeted collections would be needed to yield better adapted germplasm. Breeding to reduce the high levels of condensed tannins (>13% of DM) to moderate concentrations in Dorycnium might improve forage digestibility and could have positive implications for animal performance and health. Despite the poor digestibility of some Dorycnium species (<60% DM digestibility), these plants may still play a significant role as drought forage to provide feed when other forage sources are in limited supply. Further research is required to quantify the potential of Dorycnium species for commercial release and to determine how these plants should be best managed and integrated into livestock and mixed cropping systems.
{"title":"Prospects for three Dorycnium species as forage plants in agricultural systems: a review of their agronomic characteristics","authors":"L. Bell, M. Ryan, M. Ewing, G. Moore, P. Lane","doi":"10.1071/EA07109","DOIUrl":"https://doi.org/10.1071/EA07109","url":null,"abstract":"Perennial legumes in the Dorycnium genus may have potential as forage plants that could reduce the seasonality of feed production and improve the sustainability of agricultural systems. However, Dorycnium species are not currently used commercially and little is known about their agronomic characteristics. This review covers the current knowledge on Dorycnium distribution, taxonomy and the agronomic performance of Dorycnium hirsutum, Dorycnium rectum and Dorycnium pentaphyllum, including adaptation, establishment, biomass production, water use, grazing management and nitrogen fixation, along with considerations for animal production. Dorycnium originate from temperate Europe and the Mediterranean basin and may be suitable for other regions with similar climatic conditions. Little data exist on the climatic and edaphic conditions to which Dorycnium species are best adapted. Current evidence suggests that D. hirsutum is widely adapted and might be suitable as a forage plant for acid soils in drier and frost-prone agricultural regions. D. hirsutum also persists well in low rainfall environments (down to 300 mm mean annual rainfall), can produce up to 21 t dry matter(DM)/ha in its first 3 years and, by utilising extra water compared with annual pastures, can reduce water leakage below the root zone, thereby slowing development of dryland salinity. The use of D. rectum would be limited to high rainfall or water-accumulating sites. D. pentaphyllum is a diverse species, yet available material appears to be less productive but has better forage quality than D. hirsutum. Currently, establishment reliability and/or forage digestibility are major limitations of the tested Dorycnium species that restrict their potential role and challenge the feasibility of their future use. Breeding may overcome or minimise these limitations and improved agronomic management might also enhance their usefulness. However, current collected genetic resources of Dorycnium are very limited and targeted collections would be needed to yield better adapted germplasm. Breeding to reduce the high levels of condensed tannins (>13% of DM) to moderate concentrations in Dorycnium might improve forage digestibility and could have positive implications for animal performance and health. Despite the poor digestibility of some Dorycnium species (<60% DM digestibility), these plants may still play a significant role as drought forage to provide feed when other forage sources are in limited supply. Further research is required to quantify the potential of Dorycnium species for commercial release and to determine how these plants should be best managed and integrated into livestock and mixed cropping systems.","PeriodicalId":8636,"journal":{"name":"Australian Journal of Experimental Agriculture","volume":"48 1","pages":"467-479"},"PeriodicalIF":0.0,"publicationDate":"2008-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58790652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mycotoxin contamination of Australian maize is neither common nor extensive, but has the capacity to seriously disrupt marketing. Low to moderate levels of aflatoxins and fumonisins can be widespread in some seasons, but zearalenone, nivalenol and deoxynivalenol are usually confined to small growing localities. Possible approaches to such situations were tested by an analysis of several case studies. It is concluded that communication and coordination across the industry, prediction and prevention of contamination, rapid detection and assessment of contamination, effective use of contaminated maize and breeding for resistance comprise a useful set of strategies for managing mycotoxins in maize.
{"title":"Managing mycotoxins in maize: case studies","authors":"B. Blaney, K. K'Keeffe, L. Bricknell","doi":"10.1071/EA06095","DOIUrl":"https://doi.org/10.1071/EA06095","url":null,"abstract":"Mycotoxin contamination of Australian maize is neither common nor extensive, but has the capacity to seriously disrupt marketing. Low to moderate levels of aflatoxins and fumonisins can be widespread in some seasons, but zearalenone, nivalenol and deoxynivalenol are usually confined to small growing localities. Possible approaches to such situations were tested by an analysis of several case studies. It is concluded that communication and coordination across the industry, prediction and prevention of contamination, rapid detection and assessment of contamination, effective use of contaminated maize and breeding for resistance comprise a useful set of strategies for managing mycotoxins in maize.","PeriodicalId":8636,"journal":{"name":"Australian Journal of Experimental Agriculture","volume":"48 1","pages":"351-357"},"PeriodicalIF":0.0,"publicationDate":"2008-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58784729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Birch, D. Thornby, S. Adkins, B. Andrieu, J. Hanan
Two field experiments using maize (Pioneer 31H50) and three watering regimes [(i) irrigated for the whole crop cycle, until anthesis, (ii) not at all (experiment 1) and (iii) fully irrigated and rain grown for the whole crop cycle (experiment 2)] were conducted at Gatton, Australia, during the 2003–04 season. Data on crop ontogeny, leaf, sheath and internode lengths and leaf width, and senescence were collected at 1- to 3-day intervals. A glasshouse experiment during 2003 quantified the responses of leaf shape and leaf presentation to various levels of water stress. Data from experiment 1 were used to modify and parameterise an architectural model of maize (ADEL-Maize) to incorporate the impact of water stress on maize canopy characteristics. The modified model produced accurate fitted values for experiment 1 for final leaf area and plant height, but values during development for leaf area were lower than observed data. Crop duration was reasonably well fitted and differences between the fully irrigated and rain-grown crops were accurately predicted. Final representations of maize crop canopies were realistic. Possible explanations for low values of leaf area are provided. The model requires further development using data from the glasshouse study and before being validated using data from experiment 2 and other independent data. It will then be used to extend functionality in architectural models of maize. With further research and development, the model should be particularly useful in examining the response of maize production to water stress including improved prediction of total biomass and grain yield. This will facilitate improved simulation of plant growth and development processes allowing investigation of genotype by environment interactions under conditions of suboptimal water supply.
{"title":"Architectural modelling of maize under water stress","authors":"C. Birch, D. Thornby, S. Adkins, B. Andrieu, J. Hanan","doi":"10.1071/EA06105","DOIUrl":"https://doi.org/10.1071/EA06105","url":null,"abstract":"Two field experiments using maize (Pioneer 31H50) and three watering regimes [(i) irrigated for the whole crop cycle, until anthesis, (ii) not at all (experiment 1) and (iii) fully irrigated and rain grown for the whole crop cycle (experiment 2)] were conducted at Gatton, Australia, during the 2003–04 season. Data on crop ontogeny, leaf, sheath and internode lengths and leaf width, and senescence were collected at 1- to 3-day intervals. A glasshouse experiment during 2003 quantified the responses of leaf shape and leaf presentation to various levels of water stress. Data from experiment 1 were used to modify and parameterise an architectural model of maize (ADEL-Maize) to incorporate the impact of water stress on maize canopy characteristics. The modified model produced accurate fitted values for experiment 1 for final leaf area and plant height, but values during development for leaf area were lower than observed data. Crop duration was reasonably well fitted and differences between the fully irrigated and rain-grown crops were accurately predicted. Final representations of maize crop canopies were realistic. Possible explanations for low values of leaf area are provided. The model requires further development using data from the glasshouse study and before being validated using data from experiment 2 and other independent data. It will then be used to extend functionality in architectural models of maize. With further research and development, the model should be particularly useful in examining the response of maize production to water stress including improved prediction of total biomass and grain yield. This will facilitate improved simulation of plant growth and development processes allowing investigation of genotype by environment interactions under conditions of suboptimal water supply.","PeriodicalId":8636,"journal":{"name":"Australian Journal of Experimental Agriculture","volume":"48 1","pages":"335-341"},"PeriodicalIF":0.0,"publicationDate":"2008-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1071/EA06105","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58785490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Birch, K. Stephen, G. McLean, A. Doherty, G. Hammer, M. Robertson
Maize may assume a more significant role in grain crop production systems in north-east Australia if the probability of producing low yields associated with given amounts of available water can be reduced. Growing hybrids with very early maturity provides a possible way to achieve this. Simulation studies of dryland maize production in areas of highly variable rainfall in north-east Australia were undertaken using long-term weather data input to the APSIM model configured for quick to medium maturity maize. The studies focussed on sowing time options, population density, cultivars, and water availability at sowing. Simulation outputs included predicted mean and median yield, measures of yield variability, and the probability of producing low to very low yield (< 2 t/ha). The study showed that optimum sowing date varied with location, and that low populations gave more reliable production, despite some potential yield losses in favourable years. The results of the simulation study provide estimates of yield and thus economic viability of maize production that are interpreted in terms of seasonal variability. They indicate that maize is a viable dryland cropping option provided that cultivar, sowing time and starting water conditions are optimised. Non-optimal conditions of water supply at sowing should be avoided, as greater variability in yield and reduced viability are predicted.
{"title":"Reliability of production of quick to medium maturity maize in areas of variable rainfall in north-east Australia","authors":"C. Birch, K. Stephen, G. McLean, A. Doherty, G. Hammer, M. Robertson","doi":"10.1071/EA06104","DOIUrl":"https://doi.org/10.1071/EA06104","url":null,"abstract":"Maize may assume a more significant role in grain crop production systems in north-east Australia if the probability of producing low yields associated with given amounts of available water can be reduced. Growing hybrids with very early maturity provides a possible way to achieve this. Simulation studies of dryland maize production in areas of highly variable rainfall in north-east Australia were undertaken using long-term weather data input to the APSIM model configured for quick to medium maturity maize. The studies focussed on sowing time options, population density, cultivars, and water availability at sowing. Simulation outputs included predicted mean and median yield, measures of yield variability, and the probability of producing low to very low yield (< 2 t/ha). The study showed that optimum sowing date varied with location, and that low populations gave more reliable production, despite some potential yield losses in favourable years. The results of the simulation study provide estimates of yield and thus economic viability of maize production that are interpreted in terms of seasonal variability. They indicate that maize is a viable dryland cropping option provided that cultivar, sowing time and starting water conditions are optimised. Non-optimal conditions of water supply at sowing should be avoided, as greater variability in yield and reduced viability are predicted.","PeriodicalId":8636,"journal":{"name":"Australian Journal of Experimental Agriculture","volume":"48 1","pages":"326-334"},"PeriodicalIF":0.0,"publicationDate":"2008-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58785393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Foreword to 'Water to Gold'","authors":"L. Humphreys, Kieran O'Keeffe, N. Hutchins","doi":"10.1071/EA07990_FO","DOIUrl":"https://doi.org/10.1071/EA07990_FO","url":null,"abstract":"","PeriodicalId":8636,"journal":{"name":"Australian Journal of Experimental Agriculture","volume":"48 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2008-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58799801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aflatoxins are highly carcinogenic mycotoxins produced by two fungi, Aspergillus flavus and A. parasiticus, under specific moisture and temperature conditions before harvest and/or during storage of a wide range of crops including maize. Modelling of interactions between host plant and environment during the season can enable quantification of preharvest aflatoxin risk and its potential management. A model was developed to quantify climatic risks of aflatoxin contamination in maize using principles previously used for peanuts. The model outputs an aflatoxin risk index in response to seasonal temperature and soil moisture during the maize grain filling period using the APSIM’s maize module. The model performed well in simulating climatic risk of aflatoxin contamination in maize as indicated by a significant R2 (P ≤ 0.01) between aflatoxin risk index and the measured aflatoxin B1 in crop samples, which was 0.69 for a range of rainfed Australian locations and 0.62 when irrigated locations were also included in the analysis. The model was further applied to determine probabilities of exceeding a given aflatoxin risk in four non-irrigated maize growing locations of Queensland using 106 years of historical climatic data. Locations with both dry and hot climates had a much higher probability of higher aflatoxin risk compared with locations having either dry or hot conditions alone. Scenario analysis suggested that under non-irrigated conditions the risk of aflatoxin contamination could be minimised by adjusting sowing time or selecting an appropriate hybrid to better match the grain filling period to coincide with lower temperature and water stress conditions.
{"title":"Modelling climatic risks of aflatoxin contamination in maize","authors":"Y. Chauhan, G. Wright, N. Rachaputi","doi":"10.1071/EA06101","DOIUrl":"https://doi.org/10.1071/EA06101","url":null,"abstract":"Aflatoxins are highly carcinogenic mycotoxins produced by two fungi, Aspergillus flavus and A. parasiticus, under specific moisture and temperature conditions before harvest and/or during storage of a wide range of crops including maize. Modelling of interactions between host plant and environment during the season can enable quantification of preharvest aflatoxin risk and its potential management. A model was developed to quantify climatic risks of aflatoxin contamination in maize using principles previously used for peanuts. The model outputs an aflatoxin risk index in response to seasonal temperature and soil moisture during the maize grain filling period using the APSIM’s maize module. The model performed well in simulating climatic risk of aflatoxin contamination in maize as indicated by a significant R2 (P ≤ 0.01) between aflatoxin risk index and the measured aflatoxin B1 in crop samples, which was 0.69 for a range of rainfed Australian locations and 0.62 when irrigated locations were also included in the analysis. The model was further applied to determine probabilities of exceeding a given aflatoxin risk in four non-irrigated maize growing locations of Queensland using 106 years of historical climatic data. Locations with both dry and hot climates had a much higher probability of higher aflatoxin risk compared with locations having either dry or hot conditions alone. Scenario analysis suggested that under non-irrigated conditions the risk of aflatoxin contamination could be minimised by adjusting sowing time or selecting an appropriate hybrid to better match the grain filling period to coincide with lower temperature and water stress conditions.","PeriodicalId":8636,"journal":{"name":"Australian Journal of Experimental Agriculture","volume":"70 1","pages":"358-366"},"PeriodicalIF":0.0,"publicationDate":"2008-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1071/EA06101","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58785270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The life cycle assessment component of this multi-institutional project determined greenhouse gas emissions in pre-farm, on-farm and post-farm activities involved in the use of maize for the manufacture of corn chips. When the emissions were expressed in terms of carbon dioxide-equivalents (CO2-e), pre-farm emissions comprised ~6% of the life cycle emissions, on-farm activities comprised ~36% and post-farm activities accounted for ~58% of life cycle greenhouse gas emissions. We used one 400 g packet of corn chips as the functional unit. The single largest source of greenhouse emissions was the emission of nitrous oxide on the farm as a result of fertiliser application (0.126 kg CO2-e per packet). The next largest was electricity used during the manufacture of the corn chips (0.086 kg CO2-e per packet). The manufacture of the packaging (box plus packet, being 0.06 kg CO2-e) was the next largest source and then the oil for frying the corn chips (0.048 kg CO2-e per packet). Greenhouse gas emissions from fertiliser application were primarily nitrous oxide (N2O), which has a global warming potential of 310 kg CO2-e/kg N2O. In typical irrigated farm systems, these emissions, when converted to CO2-e, are almost three times more than the greenhouse gas emissions that result from energy used to pump water. However, pumping irrigation water from deep bores currently produces greenhouse gas emissions that are almost three times those from irrigation using surface waters. Greenhouse gas emissions from the use of tractors on typical farms are about one-third of the emissions from pumping water. Farm management techniques can be used to increase soil carbon and reduce greenhouse gas emissions. If farms that currently burn stubble were to implement stubble incorporation then, in the absence of other changes to the supply chain, they will achieve a 30% reduction in emissions from ‘cradle to farm-gate’. In absolute terms, when the soil carbon dioxide is included (even though soil carbon dioxide in this instance is not counted as a greenhouse gas in national and international greenhouse gas inventories), our measurements indicate that carbon dioxide and greenhouse gas emissions from farms that produce maize using stubble incorporation are 56% lower than emissions from farms that burn their stubble. The pre-farm and on-farm operations add $0.40 value per kg of CO2-e greenhouse gas emitted. Post-farm processing added $2 value per kg of CO2-e greenhouse gas emitted. Processing maize for corn chips emitted more greenhouse gases than processing the same amount of corn for starch or ethanol.
{"title":"Life cycle assessment of greenhouse gas emissions from irrigated maize and their significance in the value chain.","authors":"T. Grant, T. Beer","doi":"10.1071/EA06099","DOIUrl":"https://doi.org/10.1071/EA06099","url":null,"abstract":"The life cycle assessment component of this multi-institutional project determined greenhouse gas emissions in pre-farm, on-farm and post-farm activities involved in the use of maize for the manufacture of corn chips. When the emissions were expressed in terms of carbon dioxide-equivalents (CO2-e), pre-farm emissions comprised ~6% of the life cycle emissions, on-farm activities comprised ~36% and post-farm activities accounted for ~58% of life cycle greenhouse gas emissions. We used one 400 g packet of corn chips as the functional unit. The single largest source of greenhouse emissions was the emission of nitrous oxide on the farm as a result of fertiliser application (0.126 kg CO2-e per packet). The next largest was electricity used during the manufacture of the corn chips (0.086 kg CO2-e per packet). The manufacture of the packaging (box plus packet, being 0.06 kg CO2-e) was the next largest source and then the oil for frying the corn chips (0.048 kg CO2-e per packet). Greenhouse gas emissions from fertiliser application were primarily nitrous oxide (N2O), which has a global warming potential of 310 kg CO2-e/kg N2O. In typical irrigated farm systems, these emissions, when converted to CO2-e, are almost three times more than the greenhouse gas emissions that result from energy used to pump water. However, pumping irrigation water from deep bores currently produces greenhouse gas emissions that are almost three times those from irrigation using surface waters. Greenhouse gas emissions from the use of tractors on typical farms are about one-third of the emissions from pumping water. Farm management techniques can be used to increase soil carbon and reduce greenhouse gas emissions. If farms that currently burn stubble were to implement stubble incorporation then, in the absence of other changes to the supply chain, they will achieve a 30% reduction in emissions from ‘cradle to farm-gate’. In absolute terms, when the soil carbon dioxide is included (even though soil carbon dioxide in this instance is not counted as a greenhouse gas in national and international greenhouse gas inventories), our measurements indicate that carbon dioxide and greenhouse gas emissions from farms that produce maize using stubble incorporation are 56% lower than emissions from farms that burn their stubble. The pre-farm and on-farm operations add $0.40 value per kg of CO2-e greenhouse gas emitted. Post-farm processing added $2 value per kg of CO2-e greenhouse gas emitted. Processing maize for corn chips emitted more greenhouse gases than processing the same amount of corn for starch or ethanol.","PeriodicalId":8636,"journal":{"name":"Australian Journal of Experimental Agriculture","volume":"48 1","pages":"375-381"},"PeriodicalIF":0.0,"publicationDate":"2008-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1071/EA06099","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58785146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recent incidents of mycotoxin contamination (particularly aflatoxins and fumonisins) have demonstrated a need for an industry-wide management system to ensure Australian maize meets the requirements of all domestic users and export markets. Results of recent surveys are presented, demonstrating overall good conformity with nationally accepted industry marketing standards but with occasional samples exceeding these levels. This paper describes mycotoxin-related hazards inherent in the Australian maize production system and a methodology combining good agricultural practices and the hazard analysis critical control point framework to manage risk.
{"title":"Risk management for mycotoxin contamination of Australian maize","authors":"L. Bricknell, B. Blaney, J. Ng","doi":"10.1071/EA06096","DOIUrl":"https://doi.org/10.1071/EA06096","url":null,"abstract":"Recent incidents of mycotoxin contamination (particularly aflatoxins and fumonisins) have demonstrated a need for an industry-wide management system to ensure Australian maize meets the requirements of all domestic users and export markets. Results of recent surveys are presented, demonstrating overall good conformity with nationally accepted industry marketing standards but with occasional samples exceeding these levels. This paper describes mycotoxin-related hazards inherent in the Australian maize production system and a methodology combining good agricultural practices and the hazard analysis critical control point framework to manage risk.","PeriodicalId":8636,"journal":{"name":"Australian Journal of Experimental Agriculture","volume":"48 1","pages":"342-350"},"PeriodicalIF":0.0,"publicationDate":"2008-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58784791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper reports on the use of APSIM - Maize for retrospective analysis of performance of a high input, high yielding maize crop and analysis of predicted performance of maize grown with high inputs over the long-term (>100 years) for specified scenarios of environmental conditions (temperature and radiation) and agronomic inputs (sowing date, plant population, nitrogen fertiliser and irrigation) at Boort, Victoria, Australia. It uses a high yielding (17 400 kg/ha dry grain, 20 500 kg/ha at 15% water) commercial crop grown in 2004-05 as the basis of the study. Yield for the agronomic and environmental conditions of 2004-05 was predicted accurately, giving confidence that the model could be used for the detailed analyses undertaken. The analysis showed that the yield achieved was close to that possible with the conditions and agronomic inputs of 2004-05. Sowing dates during 21 September to 26 October had little effect on predicted yield, except when combined with reduced temperature. Single year and long-term analyses concluded that a higher plant population (11 plants/m2) is needed to optimise yield, but that slightly lower N and irrigation inputs are appropriate for the plant population used commercially (8.4 plants/m2). Also, compared with changes in agronomic inputs increases in temperature and/or radiation had relatively minor effects, except that reduced temperature reduces predicted yield substantially. This study provides an approach for the use of models for both retrospective analysis of crop performance and assessment of long-term variability of crop yield under a wide range of agronomic and environmental conditions.
{"title":"Analysis of high yielding maize production – a study based on a commercial crop","authors":"C. Birch, G. McLean, A. Sawers","doi":"10.1071/EA06103","DOIUrl":"https://doi.org/10.1071/EA06103","url":null,"abstract":"This paper reports on the use of APSIM - Maize for retrospective analysis of performance of a high input, high yielding maize crop and analysis of predicted performance of maize grown with high inputs over the long-term (>100 years) for specified scenarios of environmental conditions (temperature and radiation) and agronomic inputs (sowing date, plant population, nitrogen fertiliser and irrigation) at Boort, Victoria, Australia. It uses a high yielding (17 400 kg/ha dry grain, 20 500 kg/ha at 15% water) commercial crop grown in 2004-05 as the basis of the study. Yield for the agronomic and environmental conditions of 2004-05 was predicted accurately, giving confidence that the model could be used for the detailed analyses undertaken. The analysis showed that the yield achieved was close to that possible with the conditions and agronomic inputs of 2004-05. Sowing dates during 21 September to 26 October had little effect on predicted yield, except when combined with reduced temperature. Single year and long-term analyses concluded that a higher plant population (11 plants/m2) is needed to optimise yield, but that slightly lower N and irrigation inputs are appropriate for the plant population used commercially (8.4 plants/m2). Also, compared with changes in agronomic inputs increases in temperature and/or radiation had relatively minor effects, except that reduced temperature reduces predicted yield substantially. This study provides an approach for the use of models for both retrospective analysis of crop performance and assessment of long-term variability of crop yield under a wide range of agronomic and environmental conditions.","PeriodicalId":8636,"journal":{"name":"Australian Journal of Experimental Agriculture","volume":"48 1","pages":"296-303"},"PeriodicalIF":0.0,"publicationDate":"2008-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1071/EA06103","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58785333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anaerobic digestion and electrochemical oxidation were investigated for their potential to recycle carbon and degrade nitrogen from dairy manure; the energy balance of this combination of treatments was also evaluated. Anaerobic digestion is a sustainable technology that allows recovery of biomass energy and treatment of animal wastes for carbon recycling. Since the anaerobic digestion process performs denitrification poorly, almost all nitrogenous substances are discharged in digested effluent as ammonia. The ammonium nitrogen in anaerobically digested effluent is degraded by electrochemical oxidation with an unsacrificial anode. The electrochemical oxidation requires inputs of electricity. We evaluated the feasibility of using electricity generated by a full-scale biogas plant, producing biogas from dairy manure, for the electrochemical oxidation of ammonium nitrogen in anaerobically digested effluent. Data on the amount of electricity generated by such a plant were compared with data on the electricity requirements of the electrochemical oxidation process to determine the energy balance of the two processes. The results indicated that electricity generated from a biogas plant was able to supply 24 to 33% of the electricity required for the electrochemical oxidation.
{"title":"Nitrogen and energy balances of a combined anaerobic digestion and electrochemical oxidation process for dairy manure management","authors":"I. Ihara, K. Toyoda, Tsuneo Watanabe, K. Umetsu","doi":"10.1071/EA07254","DOIUrl":"https://doi.org/10.1071/EA07254","url":null,"abstract":"Anaerobic digestion and electrochemical oxidation were investigated for their potential to recycle carbon and degrade nitrogen from dairy manure; the energy balance of this combination of treatments was also evaluated. Anaerobic digestion is a sustainable technology that allows recovery of biomass energy and treatment of animal wastes for carbon recycling. Since the anaerobic digestion process performs denitrification poorly, almost all nitrogenous substances are discharged in digested effluent as ammonia. The ammonium nitrogen in anaerobically digested effluent is degraded by electrochemical oxidation with an unsacrificial anode. The electrochemical oxidation requires inputs of electricity. We evaluated the feasibility of using electricity generated by a full-scale biogas plant, producing biogas from dairy manure, for the electrochemical oxidation of ammonium nitrogen in anaerobically digested effluent. Data on the amount of electricity generated by such a plant were compared with data on the electricity requirements of the electrochemical oxidation process to determine the energy balance of the two processes. The results indicated that electricity generated from a biogas plant was able to supply 24 to 33% of the electricity required for the electrochemical oxidation.","PeriodicalId":8636,"journal":{"name":"Australian Journal of Experimental Agriculture","volume":"48 1","pages":"208-212"},"PeriodicalIF":0.0,"publicationDate":"2008-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1071/EA07254","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58795367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：