See the Department of Agriculture and Food, Western Australia's (DAFWA) PestFax newsletter for updates on the status of this pest.
We need your help with continued surveillance
With heightened activity forecast for aphids in WA, (DAFWA) is urging growers to keep an eye out for RWA when surveying for other aphids.
It would help DAFWA’s RWA surveillance program if growers could report the absence of aphids, rather than just the presence.
This can provide an opportunity to help determine whether or not RWA is present in WA. An easy reporting option is to download DAFWA’s MyPestGuide Reporter app or make an online report. Both can be done from mypestguide.agric.wa.gov.au. If you don’t find anything, just report ‘0’. For other reporting options see below.
Agronomists, consultants, nursery and garden industry representatives and the general public can also help with surveillance:
- LOOK in crops and grassy weeds (Poaceae) for aphids or damage symptoms.
- REPORT both absence and presence.
- DO NOT send samples. Refer below to Warning about sending plant material samples.
- FOLLOW ON-FARM BIOSECURITY measures. This is imperative to prevent infestation of all pests and diseases - not just Russian wheat aphid. Avoid driving vehicles through crops, wash down vehicles frequently, wash hands, and brush down clothes and boots that have been in contact with each crop. Refer below to On-farm biosecurity is important.
Russian wheat aphid a more severe aphid
Russian wheat aphid is potentially a more severe pest than other aphids.
While aphid feeding damage generally results in yield losses of up to 10 per cent, in overseas crops Russian wheat aphid has caused yield losses of more than 80 per cent.
Unlike other aphids, Russian wheat aphids inject a toxin into susceptible crops, like wheat and barley, which can severely retard growth or under heavy infestations, kill the plant.
Although, at this point we do not know how it will affect cereal crops in Australian conditions.
What to look for
Search cereal crops and grasses for aphid pests and damage symptoms now – even before feeding damage symptoms occur.
Plant damage symptoms
- Symptoms could look like herbicide damage, thrips damage, mite damage or wheat streak damage.
- Look for a noticeable loss of green colouration across the crop and, on closer inspection, white, yellow, purple or red streaking, leaf curling, stunted plant growth and loss of vigour.
- Start plant inspections at the crop edge, where pests often colonise first, or where plants are under stress.
- Look for aphid damage symptoms near the base of newly emerged leaves and inspect the leaves and leaf whorls of tillers.
- Russian wheat aphids looks similar to other cereal aphids except it has two tiny tails at the rear end and lacks the usual excretion tubes or exhaust pipes on the top of the rear end of the body compared to other cereal aphids.
- These pests are approximately 2 millimetres long, pale yellowish green with a fine waxy coating.
- The antennae are short, as are the cone-shaped siphunculi (sometimes called cornicles).
- Examine them closely using a hand lens or smartphone macro lens.