ARS | Publication request: THE GENETIC CONTROL OF MAYSIN SYNTHESIS AND CORN EARWORM RESISTANCE IN MAIZE

Submitted to: Illinois Corn Breeders School Proceedings
Publication Type: Proceedings
Publication Acceptance Date: March 1, 1997
Publication Date: N/A

Technical Abstract: The interpretation of quantitative trait locus (QTL) studies is limited by the lack of information on metabolic pathways leading to most economic traits. Inferences about the roles of the underlying genes with a pathway or the nature of their interaction with other loci are generally not possible. An exception is resistance to the corn earworm (CEW), Helicoverpa zea (Boddie), in maize due to maysin, a C-glycosyl flavone, synthesized in silks via a branch of the well characterized flavonoid pathway. Our results using flavone synthesis as a model QTL system indicate: 1) the importance of regulatory loci as QTLs, 2) the importance of interconnection biochemical pathways on product levels, 3) evidence for "channeling" of intermediates, allowing independent synthesis of related compounds, 4) the utility of QTL analysis in clarifying the role of specific genes in a biochemical pathway, and 5) identification of a previously unknown locus on chromosome 9S affecting flavone level in three different populations.