The genus Crocus shows few phylogenetic patterns below the level of series Crocus. Alsayied et al. use inter-retroelement amplified polymorphisms to examine diversity and relationships in series Crocus, including saffron (Crocus sativus), a sterile triploid. They detect high levels of polymorphism within and between sexually reproducing Crocus species, but no polymorphisms are seen among 17 C. sativus accessions, so saffron is most likely a single allotriploid clone, and C. cartwrightianus and C. pallasii subsp. pallasii (or close relatives) are the most likely ancestors. These results may facilitate resynthesizing saffron with improved characteristics, and show the need for conservation and collection of wild Crocus.
High levels of polymorphism exist within and between sexually reproducing Crocus species except 17 C. sativus accessions, where polymorphisms are absent.