Evaluation and economic assessment of multiple insecticide strategies for managing pest complexes in sorghum (Sorghum bicolor (L.) Moench)

Managing pest complexes with multiple insecticide applications increases input costs and may prohibit production of crops in environments that limit yield. Sorghum, Sorghum bicolor (L.) Moench, is grown in drought prone regions due to its production ability in water limited environments. However, grain yield often is variable and considerably reduced in arid or drought prone regions marginalizing profitability of this crop. Rice stink bug, Oebalus pugnax (Fabricius) , corn earworm, Helicoverpa zea (Boddie), and fall armyworm, Spodoptera frugiperda (J. E. Smith), feed on developing grain in sorghum. Although rice stink bug is and occasional pest of sorghum, corn earworm and fall armyworm more commonly are treated by Texas sorghum producers to prevent economic loss of grain yield. Sugarcane aphid, Melanaphis sacchari (Zehntner), is a new pest of sorghum grown in the United States.  The aphid has a high reproductive capability and has become an economic pest of sorghum. Additional insecticide applications for sugarcane aphid have added to sorghum production costs and may limit its profitability in water limited environments. The current study evaluates multiple insecticides to suppress rice stink bug, corn earworm, fall armyworm, and sugarcane aphid to determine the best combination of products for management of this sorghum insect complex. An economic analyses of management options that offer pest suppression at the least cost also are reported.