As the earlier plantings of sorghum progress through flowering, moderate to high Helicoverpa pressure means that many crops have caterpillar numbers over threshold. Nucleopolyhedrovirus (NPV) is one of the main insecticides used to control Helicoverpa larvae in sorghum, however prevailing conditions play an important role in the speed and level of control achieved with NPV.
As the cotton season gets underway aphids are starting to be detected in crops, on ratoons, volunteers and weeds. Last season, there were some regions where Cotton Bunchy Top (CBT) was detected in crops towards the end of the season. To assess and manage the risk of yield loss caused by CBT, and minimise the difficulties of controlling insecticide resistant… Read more »
More than 50 researchers, extension staff and industry representatives attended this year’s IPM forum in Toowoomba. The IPM forum is an annual event and brings together researchers and industry to discuss the latest research and developments in pest management for the Northern region. Topics presented at the forum consist of a mix of current research and industry-ready research outcomes. Below… Read more »
Two spotted mites (TSM) or red spider mites have been reported in damaging numbers in many mungbean crops on the Darling Downs and in Northern NSW. Crops at particular risk are those adjacent to maturing cotton (or any other mite hosts) from which mites are dispersing in large numbers. As TSM are very small (0.5 mm) the first evidence of their… Read more »
Over the past few weeks there have been reports of cotton stainers in cotton crops in Central Queensland and on the Darling Downs. This week we received photographs of ‘stainers’ from CQ which raised the importance of correct identification.
Helicoverpa populations have started with a bang this season. One or more larvae per plant are common in pre-flowering sorghum, corn and cotton. However, early flowering sorghum crops are carrying up to 10 larvae per head. Corn and sorghum (monocot crops) host only Helicoverpa armigera, not H. punctigera – which has implications for control. Some key issues relevant to dealing… Read more »
In order to keep you updated with entomology activities, the following article outlines the research trials to be conducted on mirids this season on the Darling Downs by Dr Moazzem Khan (Senior Entomologist, DEEDI, Toowoomba).
With some chickpea crops being sprayed out, rather than harvested, there are reports of helicoverpa larvae surviving on crop residues. The survival of larvae, particularly large late instar larvae, poses a threat to subsequent crops that may be sown directly into the chickpea residues. It is important to check for surviving larvae under the chickpea residues before the next crop… Read more »
This winter we’ve seen several instances of severe scarab damage to winter cereals (wheat, barley and oats) , including on crops at Jandowae and Felton on the Darling Downs. The photograph below shows that severe damage is mostly confined to areas of paddocks which were previously pasture – and this is where the highest scarab populations were found.
Distinguishing ‘brown’ stink bugs from each other. Adults brown stink bugs (Dictyotus caenosus) are shield shaped, matt brown, and smaller than green vegetable bug (GVB), about 7 – 8 mm long (Plate 1). They may be confused with glossy shield bug (Cermatulus nasalis) which is a slightly larger predatory bug, and with rice spotting bug (Eysarcoris distinctus) which is smaller… Read more »
