[Investigations on the inheritance of self-fertility in rye (Secale cereale)]

The cross between the rye variety 'Petkuser Kurzstroh' and self-fertile plants of the North-American variety 'Dakold' was carried out and seed setting of the F 1-generation and of the F 2- and F 3-generation produced by selfing was studied. In most cases seed setting was very high, only a few plants were self sterile, with fertile seeds ranging from 0-5 percent. Differences in the degree of fertility in the group of self-fertile plants are inherited and explained by subvital genes, which are not necessarily connected with the incompatibility system. To get more information on the inheritance of the self-fertility introduced by the variety 'Dakold' pollen tube growth after selfing and crossing within the progenies was studied with the help of the petri dish technique. On the basis of the results it is concluded that self-fertility is not caused by an allele of one of the incompatibility loci but by a third factor. Synergic action of this factor with the incompatibility genes and the possible interaction between the alleles of the incompatibility loci of the two different parents are discussed.