by Kay Ledbetter, Texas A&M AgriLife Communications
AMARILLO – Sugarcane aphid populations are exploding in grain sorghum fields across the Texas High Plains, warns a Texas A&M AgriLife Extension Service specialist in Amarillo.
Dr. Ed Bynum, AgriLife Extension entomologist, said the sugarcane aphid populations in the South Plains have reached economic thresholds. Infestations in the field can be just a few aphids per plant to a thousand or more aphids per plant.
Infestations were found Aug. 1 in sorghum silage trials near Bushland, and there was a report of aphids in an Ochiltree County field, he said.
“We need to make sure producers are out checking their fields, scouting for the sugarcane aphid and to be prepared for when insecticide applications are warranted.”
Bynum said AgriLife Extension entomologists have advised the threshold for the High Plains is to treat when:
– 20 percent of plants have aphids in the pre-boot stage.
– 20 percent of the plants have no more than 50 aphids in the boot stage.
– 30 percent in the flowering-milk.
– 30 percent infested with localized areas of heavy honeydew and established aphid colonies in soft dough and dough stages.
– At black layer, when heavy honeydew and established aphid colonies are present. Treat only for preventing harvest problems.
Bynum said field trials have shown only two chemicals provide good control of the aphid. These products are Transform and Silvanto.
Other insecticide products that might be recommended for control have not proven to be effective in studies across Texas, he said.
“Producers can control the sugarcane aphid if they stay on top of the situation and make timely applications,” Bynum said.
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