THE GENETIC-CONTROL OF SELF-COMPATIBILITY IN AN INBRED LINE OF LOLIUM-PERENNE L

The segregating generations derived from a cross of a self-compatible with an incompatible inbred line of Lolium perenne were analysed for the incompatibility reaction as revealed by the pollen/stigma fluorescence test. All F1 plants showed a half-compatible reaction whilst segregation occurred in the F2 into half- and fully-self-compatible classes. The latter plants bred true in the F3 whilst the former once again showed the same pattern of segregation. These results indicate that the control of self-compatibility is by a single gene (Sc) which is gametophytic in action. Further analysis of an intra-F2 pollination diallel and of reciprocal cross-pollinations between F2 and F1 plants reveal that this gene is additional to the SZ incompatibility system.