Expression profile of maize´s stalk challenged with the corn borer Sesamia nonagrioides

Stalk borers are major pests for some of the most important crops in the world, such as maize or rice. Plant defense mechanisms against these herbivores have been poorly investigated. The maize´s stalk responds to insect feeding activating defense genes including hormone biosynthetic-related or proteinase inhibitor transcripts. The most outstanding conclusion is that cells in the maize´s stalk undergo cell wall fortification after corn borer tunneling. We performed a gene expression profiling to identify those genes differentially expressed in maize after infestation with the corn borer S. nonagrioides. Four genetically unrelated maize inbred lines (EP39, EP42, CM151 and PB130) were infested at VT (tasseling) developmental stage with a mass of approximately 40 eggs of S. nonagrioides laid on the sheath of the main ear. Another four biological replicates per genotype were used as control. Samples for RNA extraction were harvested fifteen days after infestation.