STRUCTURE AND EVOLUTION OF THE rp1 COMPLEX CONFERRING RUST RESISTANCE IN MAIZE

Genetic analyses of the rp1 rust resistance complex of maize have demonstrated that recombination plays a central role in the creation of genetic diversity at the locus. The generation of rp1 diversity is promoted by a high rate of intragenic recombination coupled with a tendency for genes in the complex to mispair in meiosis. Among the novel rp1 genes that have been identified include genes with novel race-specificities and genes conferring lesion mimic phenotypes. Recombinants have also been identified that confer partial resistance which is apparently non-race-specific and may be useful in controlling maize rusts in a durable manner.