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Simple sequence repeat (SSR) markers are potentiallyvaluable tools for plant breeding. The objectives ofthe work reported here were to search the EMBL andGenbank databases for the presence of SSR-containingsequences from the genus Capsicum, to assess thefrequency of different motifs, and to examine thepolymorphism of selected markers in a panel ofgenotypes, including 10 Capsicumspp. and 1tomato and 1 potato genotype. Fifty-eightmicrosatellites with different motifs were found inCapsicumsequences. A subset of twelve of thesewere selected for the polymorphism survey using PCRprimers flanking the SSR. Polymorphisms between Capsicumlines can be detected with 5 of these primerpairs. PCR products of the predicted size were alsoamplified with three primer pairs in potato and oneprimer pair in tomato. The study also showed thatshorter microsatellites could be valuable markers inCapsicum.

Both major and minor genes control the restoring of fertility in the cytoplasmic male-sterility system in pepper (Capsicum annuumL.). Bulked segregant analysis (BSA) was applied to identify molecular markers linked to a major restorer gene (Rf) using the F2population of NiujiaojiaoNo.21 (rfrf)/Xiangtanwan (RfRf). Two random amplified polymorphic DNA (RAPD) markers linked to this allele were detected with 520 decamer primers with arbitrary sequences. OP131400is a tightly linked marker with a genetic distance of0.37 cm. OW19800is on the opposite side with a distance of 8.12 cm. Both markers were repeatable and easy to score. A panel of genotypes, including 13elite inbred lines with different fertility restoring ability, were assayed for the presence ofOP131400and OW19800. The markers are absent in all sweet pepper lines, indicating that they will be most helpful for transferring Rfinto sweet pepper lines. With the aid of these markers, the size of the backcross population for testcrosses can be minimized. Furthermore, these markers will be useful in genetic analysis of the minor genes.