Corn leafhopper IPM in maize: A case study from Brazil and implications for emerging corn stunt in Alabama, USA

Corn leafhopper is a key pest of maize in Brazil, where it feeds exclusively on this crop. Its significance lies in the direct damage caused by phloem feeding and, more critically, in its role as a vector of Corn Stunt Spiroplasma and other pathogens, which can lead to severe yield losses. Although insecticide applications remain the primary IPM tool for its control, resistance to multiple modes of action has already been reported. To advance more sustainable management options, this study evaluated the role of silicon (Si) as a plant resistance inducer (PRI) against Dalbulus maidis. Silicon can enhance resistance to sap-feeding insects by reinforcing structural barriers through silica deposition and by priming plant biochemical defenses. The probing behavior of D. maidis on Si-treated corn plants was assessed using the electrical penetration graph (EPG) technique, which allows real-time monitoring of stylet activity within plant tissues. Previous studies with other hemipterans, such as Nilaparvata lugens and Schizaphis graminum, have shown that silicon alters feeding behavior. These findings support the potential of silicon to reduce D. maidis performance. Recently, corn stunt disease was detected in Alabama, raising concern about a potential future invasion of D. maidis in the region. A monitoring network is now underway in sweet corn fields to track the presence of both the diseases and vector pests. This study underscores the importance of proactive research to support future IPM strategies for this emerging threat in the Southeastern U.S.