Emergency Use Permit issued for Russian Wheat Aphid
The Australian Pesticides and Veterinary Medicines Authority (APVMA) has issued an emergency use permit (PER82792) for the use of PIRIMOR® (rate: 200-250g/ha) to control Russian Wheat Aphid (RWA) in winter cereals. The permit is valid from 8 June 2016 until 30 June 2018.
PIRIMOR has a unique 3-way action that provides fast action and rapid knockdown against aphids:
- Direct contact: PIRIMOR gives rapid knockdown of aphids. This is evident within hours under ideal conditions.
- Fumigant action: PIRIMOR produces a powerful fumigant action after application which helps control aphids which may be hidden under leaves, inside the crop canopy and shielded from direct spray contact. Fumigant activity is most evident when applying pirimicarb in temperatures above 20°C.
- Translaminar activity: PIRIMOR penetrates the upper sprayed side of leaves and moves to the underside of leaves. Any aphids sheltering on the back of leaves are controlled when feeding.
PIRIMOR is a specific aphicide which is IPM compatible. It has low risk to bees (application while bees are foraging should be avoided if possible) and other beneficial insects. This causes minimal disruption to natural predators which are important to naturally manage insect pest numbers in cereals.
Recommendations for controlling Russian Wheat Aphid (Diuraphis noxia) with PIRIMOR (under permit)
- Apply PIRIMOR at rates of 200g/ha – 250g/ha
- Use the higher label rates when:
- Weather is cool - below 20°C or when light intensity is low.
- Aphid populations are high and/or crop growth is dense.
- Consider aphid numbers and the most recent information on suggested economic thresholds (ET) for control before making the decision to spray. Note that this threshold should serve as a guide and requires validation under local conditions. ET will depend upon situation and should include consideration of factors such as crop yield potential, cost of control measure to be employed, crop growth stage and time of season, beneficial insect populations, yield loss under Australian conditions, forecast weather conditions and other insect pest species present. Prophylactic sprays are not recommend and growers should reconsider spraying where aphid numbers are low. Current economic thresholds for spraying are 20% of seedlings infested up to the start of tillering and 10% of seedlings infested thereafter, and repeat if necessary.
- Do not apply more than 2 applications per crop with a minimum re-treatment interval of 15 days.
Temperature and coverage are two important factors influencing performance of PIRIMOR.
- Optimum temperature range for application and performance of pirimicarb is between 20 and 30°C and under higher humidity conditions.
- To improve coverage and performance apply PIRIMOR in 100L/ha by boom spray or by air in 4-15L/ha.
- If spraying PIRIMOR alone: Add a non-ionic surfactant (e.g. AGRAL® @ 18mL/100) or a crop oil at 0.5% to improve coverage. A crop oil is preferred over a non-ionic surfactant when humidity is low (under high evaporation conditions).
- If tank-mixing with another product check the label or contact the company for specific surfactant recommendations.
- Avoid spraying in temperatures above 30°C due to pirimicarb loss from volatilisation and evaporation.
The first case of RWA was identified in a wheat crop at Tarlee in South Australia’s Mid North in mid-May and infestations have now spread into Victoria.
Growers and advisers are advised to look in early sown cereal crops and volunteer cereals on roadsides and in paddocks, and encouraged to report suspected sightings of RWA to the Exotic Plant Pest Hotline (1800 084 881).
For more information:
Visit the Grains Research & Development Corporation (GRDC) website at www.grdc.com.au.
Or you can download a copy of the PIRIMOR RWA Technical Note on the Syngenta website here: https://www.syngenta.com.au/cereals/insecticides/pirimor.
What is Russian wheat aphid?
Russian wheat aphid (Diuraphis noxia) is found in all major cereal production regions around the world however never in Australia before now.
It is a major pest of cereal crops that injects toxins into the plant during feeding which retards growth and with heavy infestations, kills the plant.
The aphid is spread easily by the wind and on live plant material.
Affected plants will show whitish, yellow and red leaf markings and rolling leaves.
Russian wheat aphid is approximately 2mm long, pale yellowish green with a fine waxy coating. The body is elongated compared with other cereal aphid species.
Information courtesy of Primary Industries and Regions SA, www.pir.sa.gov.au.