A PCR-based marker system monitoring CMS-(S), CMS-(T) and (N)-cytoplasm in the onion (Allium cepa L.)

The chimerical mitochondrial CMS1-specific sequence in chives (Allium schoenoprasum) was used to develop a PCR-marker that distinguishes both male-sterility inducing cytoplasms, CMS-(S) and CMS-(T), from the normal cytoplasm in onion (Allium cepa). In combination with a previously described marker for CMS-(S), which anchors in the upstream region of the mitochondrial gene cob, all of the three known cytoplasms in the onion are distinguishable. The PCR-marker system was tested in 361 onion plants, which were selected from F-1-hybrids and different open-pollinated varieties. The latter are mainly landraces from Turkey, in which all three cytoplasm types were detected.