Ongoing Results From a Candidate Gene Pipeline for Testing the Effect of DNA Sequences On Aflatoxin Accumulation and A. Flavus Resistance in Maize.

Many projects have identified candidate genes for resistance to aflatoxin accumulation or Aspergillus flavus resistance in maize using genetic mapping, large scale expression, or proteomics studies. However, only a small percentage of these candidates have been validated under field conditions and their relative contribution to resistance, if any, is unknown.   Here, we present the ongoing results of a candidate gene testing pipeline that consists of steps for identifying, testing, and verifying the association of any maize gene sequence with resistance.  The pipeline includes four QTL mapping populations and one association mapping panel, all of which have been fully phenotyped over multiple years, locations, and replications for aflatoxin accumulation resistance and associated phenotypes.  These populations have also all been genotyped with low density markers in the case of the QTL mapping populations, and high density SNP markers in the case of the association panel.  More than two dozen genes identified as possible resistance candidates from a database of previous studies, current ongoing studies, or published results, have been put into the candidate gene testing pipeline. SNPs and InDel polymorphisms within each gene that map to the correct genomic location are tested for phenotypic effect on aflatoxin accumulation resistance, and results are presented here.