What is in this article?:
- Sugarcane beetles being found in Virginia corn crop
- Seedling injury reduced
- Hot spots
• This year several crop-damaging populations of sugarcane beetles have shown up in Virginia corn fields.
• When you’ve got sugarcane beetles in your corn, there’s little you can do in terms of a curative treatment.
Seedling injury reduced
Seedling injury has also been reduced in field plots treated with a variety of different insecticides as rescue treatments including Capture 2EC, Lorsban 4EC and Baythroid 2EC. In spite of these treatments, however, significant plant injury and ultimate yield losses still occur.
In corn fields with large infestations of the insect, growers can expect severe damage to the corn root system. Young plants are the most susceptible and already several fields with damaging populations of sugarcane beetle in corn have been reported.
As it feeds, the sugarcane beetle adult chews a large gouge in the stem at the base of the plant. Eventually the damage to corn shows up as dead plants, plants with a dead heart, or stunted plants.
Damaged plants may have a light streak along the margin of the leaf. Surviving plants may develop multiple, unproductive stems.
By the time damage appears, it is often too late to replant the corn. Sugarcane beetle adults will also feed on turf and pasture grasses, causing considerable damage in some cases.
Damage occurs from late April to late May in North Carolina and Virginia.
Jimmy Ward, a local manager for Crop Production Services in Hopewell, Va., has seen a couple of corn fields hit by sugarcane beetle and on a small scale the results haven’t been pretty.
Former Isle of Wight Extension Agent and current Pioneer Agronomist Glenn Rountree says his experience with sugarcane beetle hasn’t been very encouraging either.
“I looked at an 8-9 acre field of corn (in mid-May), and the damage was bad. By bad, it was severe enough for the farmer to look at filing for crop insurance,” Rountree says.
Ward, who found the first Virginia field infested with sugarcane beetles this season says, “We found the first insects in a 10 acre field next to a hay field. The corn field had had a grass cover crop. Subsequently other fields in which sugarcane beetles were reported also were fields that had a cover crop and/or were near grass fields,” he says.
“In this particular field, smaller corn had the growing point bit out of it and was putting up multiple tillers. The larger corn was leaning over and the damage looked a lot like we typically see in zinc deficient soil.
“When we dug down at the base of the corn, about a half inch below the surface, we could easily find the small black beetles. It’s about the size of a Japanese beetle and feeding was evident on the base of the corn plant.
“In talking with people in other states who have dealt with this pest for several years, we found the beetles tend to be in areas with sod cover or with grasses. This is the type scenario in which this insect has been found so far this year in several Virginia fields,” Ward says.
“It’s going to be hard for growers to deal with these pests. Spraying in the daytime isn’t going to work, because sugarcane beetles feed mostly at night and go back underground in the daytime. It seems that daytime temperatures in the 80 degree range are a trigger for nighttime feeding,” Ward adds.
“Growers need to be aware of sugarcane beetles, but so far it has occurred very sporadically in Virginia.