Influence of parental rye on the development of embryos and endosperm of wheat–rye hybrids

Abstract

Seven lines of rye (Secale cereale L.), six inbred (S9) and one open-pollinated, were used as pollen parents in crosses with two tetraploid wheat strains (Triticum turgidum var. durum cvs. 'Jori' and 'Langdon'). The rye lines were of diverse genetic background and exhibited significant differences in meiotic stability as measured by frequencies of chiasmata and univalent formation. The rate and extent of development of the embryo and endosperm tissue of hybrid ovules were not influenced by the level of meiotic stability of the rye parent, but rather by a genetic interaction between a specific rye genotype and wheat. This was indicated by the significant differences obtained in the frequency of normal embryo formation when different rye lines were used as parents in crosses to a common wheat cultivar. The specific effect of the wheat genotype on the mean seedset was shown by the significant differences obtained when different wheat cultivars were crossed with a given set of rye genotypes under the same environmental conditions. The prevailing ambient temperature significantly affected hybrid embryo and endosperm development in vivo.