As part of the cotton industry’s proactive approach to managing resistance risks, there is an ongoing program of resistance surveillance in the major pest species. Resistance to spirotetramat (Movento®) was first detected in silverleaf whitefly (SLW) in the Burdekin region in 2016. From 2016–2024, 131 SLW populations have been collected and tested for resistance to spirotetramat, 4 populations were from… Read more »
The first major outbreak of silverleaf whitefly (SLW) in Australia occurred in 2001-02 in central Queensland. Although it hasn’t occurred again in such biblical proportions, SLW has spread across Australia and is still a pest to watch in many cotton crops, as the honeydew it secretes contaminates the lint. The original SLW threshold matrix developed in central Queensland recommended looking… Read more »
With cotton crops approaching cut-out, it’s time to make critical decisions regarding silverleaf whitefly (SLW) management. Recent hot weather has seen SLW numbers increase in many areas—indicating that a number of fields are likely to require control action soon. SLW has evolved to become one of the most complex insects to manage in a cotton system because we are essentially controlling… Read more »
The tiny wasp Eretmocerus hayati is an important natural enemy of silverleaf whitefly (SLW) and contributes to the natural biological control of this pest throughout the season. It occurs in almost all regions that grow cotton, but due to its small size (difficult to see without a hand lens) it often goes unnoticed. Like all natural enemies, Eretmocerus is susceptible… Read more »
This summer silverleaf whitefly (SLW) populations have been extremely high in many cotton crops, particularly in NSW. As these crops are defoliated, large numbers of SLW are moving out of the cotton into surrounding vegetation, including emerging grain crops. Whilst the number of SLW adults landing in seedling canola, wheat, faba beans and cereals can look dramatic, previous experience has… 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 »
Two new insecticides have recently been registered to control Bemisia tabaci B-biotype in cotton. Product Insecticide group Active ingredient Pest Exirel® anthranilic diamide (Group 28) cyantraniliprole SLW, Helicoverpa, cotton aphid (suppression only) Starkle® neonicotinoid (Group 4A) dinotefuran SLW & green mirid Exirel® was registered for cotton use in the 2013/14 season, and Starkle® has been registered for the current cotton… Read more »
Over the past couple of weeks there have been reports of whitefly adults infesting canola in the Central West and Lachlan regions of NSW. This is not an occurrence that has been recorded before, so we don’t know conclusively what the outcome will be of these infestations. What I have done is pulled together information on whitefly that will help… 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 »
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 »