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Kingaroy, Australia

Chauhan Y.S.,Fisheries and Forestry DAFF | Rachaputi R.C.N.,University of Queensland
Agricultural and Forest Meteorology | Year: 2014

The northern grains region (NGR) of Australia, which includes the state of Queensland and the northern half of the New South Wales, has highly variable climate leading to heightened production risk for all rainfed crops. Characterisation of the production environment of this region can assist in exploration of potential opportunities for reducing this risk. In this case study on mungbean (Vigna radiata L. Wilczek.) we demonstrate how this region could be characterised using the Agricultural Production Systems sIMulator (APSIM) model. The model was first evaluated for variety Crystal grown widely in the region, and then applied to simulate a water stress index (the daily supply and demand ratio) and yield from 1889 to 2012 at 28 locations. The model was run using location specific as well as three generic soils of 136, 166 and 204. mm plant available water holding capacities (PAWC). Two complementary characterisations were performed using the simulated output, one based on clustering of supply demand ratio averaged for every 100. °Cd to and from flowering, and another on clustering of percentile rankings of seasonal yield variation at different locations. Clustering of supply demand ratio revealed four drought patterns (i.e., target production environments) which commenced at different times from flowering. Seasonal frequencies of these drought patterns, which differed due to major location effects and relatively smaller soil effects, accounted for significant (~84%) variation in simulated yield. Clustering of percentile ranks corresponding to simulated yield in different seasons identified seven meaningful yield clusters. Location memberships of these yield clusters were geographically contiguous and were only slightly influenced for the lowest PAWC generic soil. All locations within these yield clusters showed a tendency to have similar seasonal drought patterns and their frequencies. Locations within different yield clusters could therefore be considered as part of distinct agro-ecoregions. These model defined agro-ecoregions could be used as selection environments for their dominant target production environment(s) to develop new genotypes and their agronomy for better adaptation and yield under variable climatic conditions. © 2014. Source

Ndungutse V.,University of Queensland | Mereddy R.,Fisheries and Forestry DAFF | Sultanbawa Y.,University of Queensland
Journal of Food Processing and Preservation | Year: 2015

The antibacterial activity and total phenolic (TP) content of Agaricus bisporus stipes were assessed using solvent and water extracts to determine its bioactivity. Extraction methods included accelerated solvent extraction (ASE) and hot water followed by membrane concentration. Water extract from ASE had the highest TP of 1.08 gallic acid equivalents (GAE)/g dry weight (DW) followed by ethanol at 0.61mg GAE/g DW and 0.11mg GAE/g DW for acetone. Acetone extracts inhibited Escherichia coli and Staphylococcus aureus at less than 50%; ethanol inhibited E.coli at 61.9% and S.aureus at 56.6%; and ASE water inhibited E.coli at 78.6% and S.aureus at 65.4%. The TP content of membrane concentrated extract of mushroom was 17mg GAE in 100mL. Membrane concentrated water extracts had a higher percentage inhibition on S.aureus than E.coli. Overall, the results were promising for further application of mushroom stipe extracts as a functional food additive. Practical Applications: Mushrooms are known for their health benefits and have been identified as a good source of nutrients. The highly perishable nature of mushrooms warrants further processing and preservation to minimize losses along the supply chain. This study explores the possibility of adding value to mushroom stipes, a by-product of the fresh mushroom industry. The extracts assessed indicate the antibacterial activity and phenolic content, and the potential of using these extracts as functional ingredients in the food industry. This study provides valuable information to the scientific community and to the industries developing novel ingredients to meet the market demand for natural food additives. © 2015 Wiley Periodicals, Inc. Source

Tridgell S.,Fisheries and Forestry DAFF
Environmental and Planning Law Journal | Year: 2013

The effectiveness of Australia's national environmental legislation - the Environment Protection and Biodiversity Conservation Act 1999 (Cth) - in protecting the environment through its environmental impact assessment regime has been a matter of ongoing debate. The administration of the Act has attracted considerable critique in terms of both its cost and its efficacy. This article revisits the debate, looking at the environmental outcomes of 50 referrals between 2008 and 2012. Some limited evidence for positive environmental outcomes is found, but in areas where there have been significant gains, new political proposals now risk eroding them. In addition, the paucity of evidence available illustrates another weakness in the Act's administration: a lack of transparency and accountability. Source

Walton D.A.,University of The Sunshine Coast | Randall B.W.,University of The Sunshine Coast | Le Lagadec M.D.,Fisheries and Forestry DAFF | Wallace H.M.,University of The Sunshine Coast
Journal of the Science of Food and Agriculture | Year: 2013

BACKGROUND: Kernel brown centres in macadamia are a defect causing internal discolouration of kernels. This study investigates the effect on the incidence of brown centres in raw kernel after maintaining high moisture content in macadamia nuts-in-shell stored at temperatures of 30°C, 35°C, 40°C and 45°C. RESULTS: Brown centres of raw kernel increased with nuts-in-shell storage time and temperature when high moisture content was maintained by sealing in polyethylene bags. Almost all kernels developed the defect when kept at high moisture content for 5 days at 45°C, and 44% developed brown centres after only 2 days of storage at high moisture content at 45°C. This contrasted with only 0.76% when stored for 2 days at 45°C but allowed to dry in open-mesh bags. At storage temperatures below 45°C, there were fewer brown centres, but there were still significant differences between those stored at high moisture content and those allowed to dry (P < 0.05). CONCLUSION: Maintenance of high moisture content during macadamia nuts-in-shell storage increases the incidence of brown centres in raw kernels and the defect increases with time and temperature. On-farm nuts-in-shell drying and storage practices should rapidly remove moisture to reduce losses. Ideally, nuts-in-shell should not be stored at high moisture content on-farm at temperatures over 30°C. © 2013 Society of Chemical Industry. Source

Ahmed F.,University of Queensland | Fanning K.,Fisheries and Forestry DAFF | Netzel M.,University of Queensland | Schenk P.M.,University of Queensland
Applied Microbiology and Biotechnology | Year: 2015

Carotenoids prevent different degenerative diseases and improve human health. Microalgae are commercially exploited for carotenoids, including astaxanthin and β-carotene. Two commercially important microalgae, Dunaliella salina and Tetraselmis suecica, were treated with plant hormones salicylic acid (SA) and methyl jasmonate (MJ), or by UV-C radiation (T. suecica only) and a combination thereof. Significant increases in total carotenoids were found for D. salina and T. suecica after treatment with MJ (10 μmol/L) and SA (70–250 μmol/L), respectively. T. suecica also had significant increases in total carotenoids following UV-C radiation compared to control cultures. Among the carotenoids, lutein was the highest induced carotenoid. A combination of these two treatments also showed a significant increase in total carotenoids and lutein for T. suecica, when compared to controls. Plant hormones and UV-C radiation may be useful tools for increasing carotenoid accumulation in green microalgae although the responses are species- and dose-specific and should be trialed in medium to large scale to explore commercial production. © 2015, Springer-Verlag Berlin Heidelberg. Source

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