Identification of the tetrad-sterility-causing Solanum stoloniferum Schltdl. & Bouché cytoplasm in interspecific hybrids with S. tuberosum L.

Tetrad sterility, in which only clumps of four premature pollen grains are released from anthers, has been observed some modern potato cultivars. It is a form cytoplasmic male sterility caused by the cytoplasm derived Mexican tetraploid species Solanum stoloniferum Schltdl. & Bouché., an important source resistance to Potato virus Y breeding. However, since S. highly polymorphic, tetrad-sterility-causing unknown among diverse accessions. In this study, we directly crossed 24 accessions with 4x tuberosum and obtained 39 hybrids 12 Nineteen six showed tetrad either D/γ- or W/γ-type cytoplasm, were triploid, tetraploid, hexaploid. The was not necessarily associated sterility. Sequence comparisons 17 mitochondrial genes their intergenic regions revealed length polymorphism region between rpl5 rps10, amplified band 859 bp This specific causing named TSCsto. 859-bp will be useful diagnostic marker for identifying TSCsto