Sugarcane Aphids: Here and Gone?
Dr. Tracy Beedy, Area Research and Extension Specialist
Dr. Tom Royer, Extension Entomology Specialist
In general, sugarcane aphid pressure in Oklahoma has been lower than was seen in 2015. While sugarcane aphids have been found in numerous fields, population pressure has been lower and numbers have not always reached treatment thresholds. The research team led by Dr. Ali Zarrabi (which includes Dr. Kristopher Giles, Dr. Beedy, Kelly Seuhs and myself) is conducting several research experiments in Lane that should help us understand how variety, management tactics and insecticides can work effectively together.
Sugarcane aphids have typically moved from Texas through Oklahoma and north into Kansas. In 2016, they spread from central Texas to southern Kansas between late June and early August (see map). They have not yet reached treatment thresholds in many of these locations.
Sugarcane aphids were found at the Research Center in Lane June 27, in KS 585 that had been planted April 26th, according to Dr. Ali Zarrabi. The field was sprayed July 12th when it reached the treatment threshold. At the same time, they were arriving in southwest Oklahoma according to Jerry Goodson, Extension Assistant at the Southwest Research and Extension center in Altus. The sorghum performance trial hosted by Alan Mindemann* near Apache was sprayed July 20th with 4oz./ac Sivanto.
Graduate research assistant, Ms. Jessica Pavlu has been surveying sorghum in various counties in Oklahoma. As of August 5, sugarcane aphids had reached treatment threshold levels in some fields in Kay, Logan, Noble and Payne, counties. She has also detected aphids in Alfalfa County that had not reached treatment thresholds.
Brook Strader* reported some scattered spraying for sugarcane aphids near O’Keene, while Brad Brainard* found that some sorghum growers were only treated for sugarcane aphids in combination with other needed spraying. In the Oklahoma Panhandle I have not found sugarcane aphids nor heard reports of them, however, they are confirmed just a few miles south, in Perryton, TX.
It is obvious from the map that sugarcane aphids do not move in an orderly procession, so it is vital to scout sorghum fields weekly when they are in the area. Current treatment thresholds for sugarcane aphid in Oklahoma is to treat when 20-30 percent of the plants are infested with one or more established colonies of sugarcane aphids. An established colony is an adult (winged or wingless) accompanied by one or more nymphs. Consult CR-7170, Management of Insect and Mite Pests in Sorghum http://pods.dasnr.okstate.edu/docushare/dsweb/Get Document-2625/CR-7170web2016.pdf for more information.
*Oklahoma Sorghum Commission member