Tight linkage between a nuclear male-sterile locus and an enzyme marker in tomato.

The linkage relationship of a nuclear male sterile locus, ms-10, was tested with two enzyme marker loci known to be on the same chromosome (long arm of chromosome 2). The results indicate the gene order is Est-1 - 18 cM - Prx-2 - 1.5 cM - ms-10. The linkage intensity of ms-10 and Prx-2 (1.5 cM) suggests that Prx-2 might provide a selectable marker for male-sterility. In accordance with this idea, the ms-10 allele was placed in cis with a rare-allele of Prx-2 (Prx-2 (1)). Selection on the basis of the codominant Prx-2 (1) allele should allow for more rapid and efficient transfer of the recessive male sterile allele into an array of genetic backgrounds, thus promoting its use in hybrid seed production.