Natural variation in maize defense against insect herbivores.

Genetic mapping projects with maize (Zea mays) have resulted in the identification of numerous quantitative trait loci (QTL) that influence resistance to insect herbivores. However, the underlying genetic basis of these QTL has been confirmed in only a small number of cases. Recent advances in genome sequencing, the development of large mapping populations, and advances in reverse genetic approaches will accelerate the discovery of novel herbivore resistance genes in maize. Areas that will merit particular research emphasis are natural variation in maize resistance to rootworms and phloem-feeding insects as well as the identification of previously unknown loci involved in the biosynthesis of maize defensive secondary metabolites.