Sugarcane aphids: A new pest in Mississippi grain sorghum

Abstract

The use of sulfoxaflor and flupyradifrone in temperatures under 15.5°C (60°F) has been believed to result in decreased efficacy in grain sorghum (Sorghum bicolor) when managing sugarcane aphids (Melanaphis sacchari). This study was conducted at the Mississippi State University R.R. Foil Plant Science Research Center to evaluate the efficacy of sulfoxaflor and flupyradifrone at 15.5°C (60°F) and 29.4°C (85°F). Asgrow ‘54-00’ was planted and treated at the soft dough growth stage with sulfoxaflor and flupyradifrone as well as an untreated check. Two inch leaf disc were removed from the uppermost leaf below the flag leaf at 0 and 24 hours and 3, 5, 7, and 10 days after treatment. Leaf disc were placed in water auger plates and infested with 5 aphids per dish and divided for each temperature tested and placed in growth chambers. Aphid mortality was recorded at 48 hours. Sulfoxaflor and Flupyradifuron both provided good control at 29.4°C but significantly less mortality at 15.5°C. regardless of timing. This data confirms that growers will likely experience unacceptable control if treating sugarcane aphids during periods cooler temperatures.