The battle with false chinch bugs in canola may be over, but these pests thrive in drought conditions and are not above targeting additional crops, such as those raised by Oklahoma sorghum and soybean growers.
These insects typically feed on plants in the mustard and beet family, but when their preferred foods dry up because of plant maturity or plants having been sprayed with a burndown before planting in no-till operations, the pests leave in search of other tasty treats.
“At this time, sorghum and double crop soybean fields are vulnerable to false chinch bug infestations,” said Phil Mulder, Oklahoma State University Cooperative Extension entomologist and head of the OSU Department of Entomology and Plant Pathology.
False chinch bugs injure plants by sucking sap which results in wilted, weakened plants. In addition to the sap loss, feeding by false chinch bug seems to produce a physical reaction in some plants.
“As examples, soybeans may exhibit a ‘burned’ appearance on the edges of the leaf blades and sorghum may turn red on the stem and leaves that are being fed upon,” Mulder said. “Young plants may be killed, resulting in stand loss.”
False chinch bugs live for about 40 days – from egg hatch through the adult stage – and go through four or more generations per year in Oklahoma.
Tom Royer, OSU Cooperative Extension integrated pest management coordinator, warns that seedling plants are particularly vulnerable to damage.
“Control is warranted if small sorghum or soybean seedlings are being killed, or when either crop is flowering and under heat stress,” he said.
Seedlings treated with an insecticide such as imidacloprid, thiamethoxam or clothianidin should be protected for 15 to 20 days. However, under extremely heavy numbers, false chinch bugs can overwhelm the plants and cause stand loss.
“If false chinch bugs are killing stands, say 5 percent to 10 percent stand loss, foliar sprays should be applied with as much water carrier as is feasible, aiming for 20 or more gallons per acre,” Royer said. “Keep checking fields because control is made more difficult due to continual migration of flying adults.”
Royer and Mulder recommend that sorghum growers institute treatment procedures if seedlings are being destroyed, or when scouting indicates more than 140 false chinch bugs per head.
Additional information is available through OSU Division of Agricultural Sciences and Natural Resources Current Report No. 7170, “Management of Sorghum Insects,” available through a producer’s local OSU Cooperative Extension county office or at http://osufacts.okstate.edu on the Internet.
Royer and Mulder recommend that soybean growers institute treatment procedures if seedlings are being destroyed.
“There is no specific product labeled for false chinch bugs control in soybeans, but products labeled for stinkbug or three-cornered alfalfa hoppers may be effective,” Royer said.
Additional information is available through OSU Division of Agricultural Sciences and Natural Resources Fact Sheet EPP-7167, “Soybean Insect Survey and Control,” available through a producer’s local OSU Cooperative Extension county office or at http://osufacts.okstate.edu on the Internet.