Phosphine alternative – Nitrogen (CRC50147) YongLin Ren James Newman Manjree Agarwal Hui Cheng Murdoch University/DAFWA biosecurity built on science Cooperative Research Centre for National Plant Biosecurity
An old thing, new again Is there anything whereof it may be said - see, this is new? It hath been already of old time, which was before us. Ecclesiastes 1, 10
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Why nitrogen again
N2 constitutes 78% of air, free source of N2 N2 is not toxic, greatly reduced OHS&E risks Provides “organic” and truly residue-free grain No resistance problems No reaction with construction materials No need for ventilation before grain can be marketed No need for product registration
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New N2 generator available on market biosecurity built on science
Pressure Swing Adsorption (PSA) N2 generator
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Membrane separation N2 generator
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Choose type of N2 plant
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Bioassays • T. Castaneum • S. Granarius • R. Dominica • T. Variabile In wheat, barley, oats, Lupins & canola
Laboratory study
Quality analysis • Moisture content • Germination • Seed colour • Oil content • Gluten & starch
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Results Adults of T. castaneum and R. dominica and S. oryzae in wheat, barley, oats, lupins and canola at 99, 98 and 97% nitrogen, complete control was achieved at 24±1°C for 2 weeks; at 30±1°C for 10 days; and at 35±1°C for 1 week
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All immature stages of T. castaneum R. dominica, S. oryzae and in wheat, barley, oats, lupins and canola at 99, 98 and 97% nitrogen, complete control was achieved at 24±2°C for 2 and 3 weeks; at 30±2°C for 2 weeks; and at 35±1°C for 1 week and 10 days All immature stages of T. variabile in wheat, barley, oats, lupins and canola 98-99% nitrogen and at 25, 30 and 35°C for 4, 3 and 2 weeks exposure period.
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All adult and all immature stages of R. dominica, S. oryzae, T. castaneum and T. variabile were controlled using the nitrogen treatment and there was no difference on mortality between phosphine-resistant and susceptible strains of these insects Adult stages of Ladybirds and Bronzed field beetles in canola were completely controlled at 95, 97 and 99% of nitrogen and 25째C for 6, 5 and 3 days
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The mortality of all stages of all insects tested increased with decreasing levels of oxygen, and increasing exposure time and temperature In comparison with wheat, barley, oats and lupin, high concentrations of nitrogen or low oxygen in canola kills all stages of all tested insects with higher efficacy
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Lake Grace trials with PSA N2 generator Aims to evaluate: Efficacy, quality and application method in 75 tonne wheat and canola silo biosecurity built on science
Results In wheat silo, all adults of T. castaneum & S. granarius were killed after one week and complete extinction of all life stages occurred after 3 weeks, but 6-10% of T. variabile larvae survived at 20°C and 96-98% N2 In canola silo, all bronzed field beetle, ladybirds & all stages of T. castaneum, S. granarius, R. dominica & T. variabile were killed at 35°C & 97% N2 with 7 day exposure Wheat quality has no change during the 3 month exposure. Canola seed colour and level of free fatty acid did not change during the 2 month storage at 35-37°C and 97% N2 biosecurity built on science
CBH Albany grain export terminal trials A 350m3/hour PSA nitrogen generator has been installed The generator is plumbed to a bank of 10x10,000 tonne concrete cells biosecurity built on science
Results After 2-3 weeks treatment with 98% nitrogen only, all barley and canola was inspected for export with no live insect pests found Ladybirds and Bronzed field beetles
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China trials with membrane separation (MS) N2 generator Aims to evaluate: • Application in horizontal storage (4,000t) • 30m3/hour MS, 99.5 purity • N2+inert dust capping
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Recirculation application method Nitrogen production (m3/hr)
50 40 30 20 PS A MS
10 0 75
80
85
90
95
Nitrogen in air (% ) biosecurity built on science
Futher work 1. To evaluate and demonstrate the membrane separation nitrogen generator and recirculation system at grower & bulk handler levels 2. To extend PSA and/or MS nitrogen technology at grower & bulk handler level 3. To evaluate high temperature (40-45ยบC) + nitrogen (95-99%) for Khapra beetle and other insect pests on grain and to develop application technologies and reducing treatment time 5. To conduct systematic laboratory and field trials to evaluate protection of colour for pulses and malting quality and colour of barley 6. To evaluate effect of high nitrogen on biology of immature stages of insect
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Thank project collaborators Ern Kostas (CBH Group) Doug Clarke (Lake Grace Farm Group) Prof. Cao Yang (Academy of Grain Science)
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Thank you  For more information, please email  y.ren@murdoch.edu.au
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