Fine mapping of the Pc locus of Sorghum bicolor, a gene controlling the reaction to a fungal pathogen and its host-selective toxin. Academic Article uri icon


  • Milo disease in sorghum is caused by isolates of the soil-borne fungus Periconia circinata that produce PC-toxin. Susceptibility to milo disease is conditioned by a single, semi-dominant gene, termed Pc. The susceptible allele (Pc) converts to a resistant form (pc) spontaneously at a gametic frequency of 10(-3) to 10(-4). A high-density genetic map was constructed around the Pc locus using DNA markers, allowing the Pc gene to be delimited to a 0.9 cM region on the short arm of sorghum chromosome 9. Physically, the Pc-region was covered by a single BAC clone. Sequence analysis of this BAC revealed twelve gene candidates. Several of the predicted genes in the region are homologous to disease resistance loci, including one NBS-LRR resistance gene analogue that is present in multiple tandem copies. Analysis of pc isolines derived from Pc/Pc sorghum suggests that one or more members of this NBS-LRR gene family are the Pc genes that condition susceptibility.

published proceedings

  • Theor Appl Genet

author list (cited authors)

  • Nagy, E. D., Lee, T., Ramakrishna, W., Xu, Z., Klein, P. E., SanMiguel, P., ... Bennetzen, J. L.

citation count

  • 27

complete list of authors

  • Nagy, Ervin D||Lee, Tso-Ching||Ramakrishna, Wusirika||Xu, Zijun||Klein, Patricia E||SanMiguel, Phillip||Cheng, Chiu-Ping||Li, Jingling||Devos, Katrien M||Schertz, Keith||Dunkle, Larry||Bennetzen, Jeffrey L

publication date

  • January 1, 2007 11:11 AM