Abstract:

Unilateral incompatibility（UI）is a kind of incompatibility that occurs in one direction only，most often when the pollen donor is self-compatible（SC）and the recipient is self-incompatible（SI）. In the present study，we identified 4 unilateral incompatibility lines（ui3a）from an introgression line（IL）population of Solanum pennellii‘LA0716’in a fresh market tomato inbred line 1052 that was developed by our group. Pollen germination test showed that the pollen viability of these ui3a lines was normal. Crosses were successful when these ui3a lines as pollen donor and the self-compatibility（SC）lines from the IL population as recipient，but not vice versa. Pollen tube growth studies indicated that the pistils of these ui3a lines rejected the pollen of themselves and self-compatibility（SC）lines from the IL population，but accept the pollen of S. peruvianum accession‘LA3858’. Subsequently，UI3a gene was fine-mapped to a 349 kb region between markers C2_At3g10220 and 1k-1294 on chromosome 3. There were 37 predicted genes in this region.

Key words: tomato, unilateral incompatibility, UI3a, fine mapping