The spread of Russian wheat aphid (RWA) (Diuraphis noxia) in the Northern grains region is considered inevitable. When it might be detected in wheat and barley is less clear as the key drivers of its spread are not well understood in Australia. Wind is likely to play a part in moving winged aphids from south to north. The most northerly… Read more »
Rutherglen bug (RGB) numbers are persisting in many sorghum crops as they start to reach physiological maturity. Queensland Department of Agriculture and Fisheries (DAF) research has shown no evidence of yield loss as a result of direct feeding on grain once it reaches physiological maturity (black layer). However, because most crops this year have staggered head emergence, there are a… Read more »
With the current season shaping up to be one of high insect pressure, we may see silverleaf whitefly (SLW), Bemisia tabaci reach problematic levels in regions outside of their traditional range. For growers and agronomists not familiar with their control it is worth investing some time to understand how one of the main registered insecticides, pyriproxyfen, works. What is pyriproxyfen?… Read more »
Solenopsis mealybug can be found throughout Queensland’s cropping areas and has also been confirmed in Western Australia, the Northern Territory and Victoria. Whilst solenopsis has not yet been confirmed in NSW cotton crops it would be reasonable to assume that it is likely to be present in the broader landscape and it is only a matter of time before it… Read more »
Large flights of helicoverpa over the last 2 weeks (or longer in some districts) have seen significant eggs lays and larval populations in winter crops, including the winter cereals. It is not unusual to find both corn earworm and armyworm in cereal crops. Correct identification of the species present is very important as it influences damage potential and choice of… Read more »
Helicoverpa punctigera numbers in pheromone traps look to be on the increase through September. The continued migration of H. punctigera through spring is likely, if suitable weather systems occur, and it is likely that all susceptible crops (chickpea, canola, faba beans, spring mungbeans, spring sunflowers) will experience helicoverpa pressure through October and November. Peter Gregg and Alice Del Socorro (University… Read more »
Key points Conditions suitable for the usual cereal aphid species will also be suitable for RWA. Aphid populations typically build rapidly in late July and August. Do not assume aphids in cereals are just the usual oat and corn aphid. In the event of a Russian wheat aphid (RWA) infestation, early detection in spring is critical to prevent yield loss…. Read more »
The National Management Group (NMG), comprising all Australian governments, Grain Producers Australia and Plant Health Australia, met on 8 June 2016 to discuss the incursion of Russian wheat aphid (Diuraphis noxia) in South Australia. Acting on advice from the Consultative Committee on Emergency Plant Pests (CCEPP), the NMG agreed that it is not technically feasible to eradicate Russian wheat aphid… Read more »
The minute two-spotted ladybird beetle (Diomus notescens) and the transverse ladybird beetle (Coccinella transversalis) are two natural enemies of cotton aphid (Aphid gossypii). They are commonly found in Australian crops, however relatively little is known about their biology. A series of laboratory experiments were conducted by the Queensland Department of Agriculture and Fisheries (DAF) to learn more about aspects of… Read more »
The South Australian government are currently responding to detections of Russian wheat aphid (Diuraphis noxia), which was initially found on a property in Tarlee in South Australia on 13 May 2106. Since the first detection, Russian wheat aphid has been found on a further 22 properties within 1,400 square kilometres, and the number is expected to rise. Investigations are underway… Read more »