Wimmera-Mallee growers advised to be aware of Wireworm activity.
BCG Staff recently spoke to growers in the Wimmera about the discovery of Wireworm in a Canola crop, resulting in approximately 120 hectares of Canola being re-sown on one property near Murtoa. Damage to Canola was also reported at a property at Natimuk.
“Two paddocks were really belted around” explained one grower “we re-sowed one, and part of another. We got the agro out after noticing some significant bare spots in the paddock and after some searching, we found them”
Wireworms can affect all winter-sown crops and are mostly found in paddocks with high stubble and crop litter contents. There are a large and varied number of species, including the grey false wireworm, the eastern false wireworm and the southern false wireworm
False wireworm larvae chew into the seedling stem and roots, weakening the plant or ring-barking the stem. The injury to the seedlings makes them susceptible to dehydration and infection by disease. Feeding damage is often most severe when germination is slowed by continued dry weather. There is evidence suggesting that stubble retention and minimum tillage are contributing to the build-up of false wireworm populations in South-eastern Australia.
“Given the green bridge we have had leading into sowing this year, there are some pests that will need closer monitoring to make sure there are no outbreaks early in the growing season,” explained Kelly Angel, Senior Manager Operations at BCG, earlier this year. “This may include species like Green Peach Aphid, Russian Wheat Aphid and the cooler conditions may also see levels of mites and Lucerne Flea increasing. It is important to remain vigilant. Seed dressings will help but they can have limitations, and growers need to ensure that spraying only occurs in response to above threshold numbers of pests rather than using an insurance policy approach. If possible and where suitable, avoid the use of broad-spectrum products to help protect beneficial species that may be present, and reduce selection pressure on non-target species. This will reduce the risk and speed at which resistant pest populations develop.”