Contributors: Susan Maas (CRDC), Lewis Wilson (CSIRO) There are currently reports of high numbers of Rutherglen bugs (RGB) in cotton across a number of growing regions (Downs, Namoi, Gwydir), and questions being asked about whether this pest can cause damage to reproductive cotton. This season has seen large spring migrations of RGB into cropping areas from Emerald to the Liverpool… Read more »
As crops come into head and start to fill grain, sorghum midge and helicoverpa will start to infest crops. Making a decision about when control is warranted is made somewhat easier with the availability of economic threshold calculators now available on the Beatsheet Blog (https://thebeatsheet.com.au/sampling-2/); or use the ready reckoners in this article. MANAGEMENT OF SORGHUM MIDGE How to count… Read more »
Since early November, large numbers of Rutherglen bug (RGB) have been migrating into cropping regions from northern NSW through to Central Queensland. Whilst the exact origin of the bugs is unknown, it is likely that they are being carried on storm fronts from inland regions where they have bred up over winter and spring on native host plants that are… Read more »
Calculating the economics of control is critical to making a decision about if and when Helicoverpa populations in chickpeas require treatment. This season, for the first time, growers and agronomists have access to an on-line calculator to help them make these decisions. The calculator overcomes the need to try and remember the formulas in the field. Best of all,… Read more »
Solenopsis mealybug (Phenacoccus solenopsis) was first identified at Emerald and the Burdekin during the 2009-10 cotton growing season. This sucking pest causes leaf distortion, stunting and reduced boll size and number. Heavy infestations can lead to plant death. Solenopsis mealybugs also produce a honeydew which affects photosynthesis and leads to sooty mould development on lint. This pest has the potential… Read more »
Results for 2011-12 Monitoring for resistance in Silverleaf whitefly, collected in the 2011-12 cotton season, is now complete. Results show that resistance exists for Admiral® and bifenthrin (e.g. Talstar®) in horticulture but not in cotton while SLW remain susceptible to Pegasus® and Movento® In total 17 collections were made from Emerald, St George, Theodore, Moree and Narrabri for resistance monitoring…. Read more »
Implications for management in grains and pulses The insecticide resistance monitoring program for Helicoverpa aims to measure resistance frequencies of field populations collected from Central Queensland through to the Riverina area of NSW. Field collections of Helicoverpa eggs are reared in the laboratory and larvae are tested with doses of insecticide that are known to kill susceptible insects. Survivors are… Read more »
There are a number of canola crops in this season, and as the weather warms up the aphid numbers are building up in some of them. The aphids that colonise canola are most commonly the cabbage and the turnip aphid. There may also be a few green peach aphid present. The aphids colonise the terminal end of the flower spike… Read more »
As the weather warms up aphid populations are becoming more obvious in crops. With aphid populations more visible in the crop, the key questions are whether they will impact on the yield of the crop, and whether it is necessary to control the aphids to avoid yield loss. Aphid infestations are widespread this year in both barley and wheat. In some instances,… Read more »
As the cotton season draws to a close it is time to for the DAFF team working on Silverleaf whitefly (SLW) resistance monitoring to start making collections of whitefly from across the cotton-growing regions. Even if SLW numbers are below threshold, it is possible for the team to make collections of either nymphs (on leaves) or adults (using the suction… Read more »
