Two stem borers in the family Crambidae, the sugarcane borer, Diatraea saccharalis, and the Mexican rice borer, Eoreuma loftini, are the most economically damaging insect pests of sugarcane (Saccharum spp. hybrids) in Louisiana. Advances in integrated pest management strategies reduced reliance on insecticides for stem borer control in the Louisiana sugarcane industry from the 1970s until the early 2000s. More recently, optimization of chemical control, renewed reliance on resistant cultivars, and improved production practices have further reduced economic impacts of the two pests to US$8 million annually, < 1% of the total crop value. Systemic activity of chlorantraniliprole provides up to ten weeks of protections, reducing the need for multiple insecticide applications in a single growing season. The negligible impact of this chemistry on key natural enemies allows for conservation biological control from two invasive predatory ants, Solenopsis invicta and Nylanderia fulva. Varietal resistance through a complex of mechanisms including rind harness and leaf sheath oppression has led to the development of resistant cultivars with 80% reductions in borer injury relative to susceptible cultivars. Collectively, these efforts have greatly reduced spring D. saccharalis populations and the number of hectares requiring insecticidal protection. Despite the reduction in insecticide use, levels of borer injury at harvest are < 1% bored internodes. Continued geographical expansion of the invasive E. loftini may lead to increases in insecticide use in the future, but recent observations suggest this borer can be managed using similar strategies to D. saccharalis.
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